apparent porosity
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R e f r a c t o r y :
Apparent porosity & Bulk Density:-
Apparent porosity:
This is the amount of the total closed and open pores in the refractory materials in
percentage.The good refractory material should have a minimum
porosity vale except in the case of the insulation bricks.
Bulk Density:
This is the ration of weight to the volume of the refractory materials in gram/cc.The
good refractory material shouls have a high bulk density value for its better
performance.
Remove the outer layer of the bricks by sample cutting machine.Take the sample size
oe 65x65x40mm and remove the moisture by putting them in air oven at 120 deg.
C.Take out and allowed to cool.Take the dry weight in gm(D).Put the samples in the
vessel containing water.Boil for about one hour.Take out and vipe out the excess water
by a wet cloth.Take the wet weight(W).The the suspended weight while the sample is
immersing in the water.(S)
(W – D)
AP% = x 100
(W-S)
W
BD gm/cc =
(W – S)
Refractoriness under load:-
The resistance of the refractory materials under specified conditions of
load,temperature,time etc.
Take the sample size of 50 mm diameter and 50 mm height(+ / - 0.5 mm) by a RUL
sample cutting machine.Calculate the area in cm2.Put the sample in the RUL testing
machine .Apply the of 2 kg per cm2.Set the dial gauge of 0.01 mm accuracy.Switch on
the RUL furnace to heta the sample.RUL temperature(t 0 C) is the temperature at
which 0.3 mm deformatation take place ie. Measure the temperature when the dedle of
the dial gauge is at 30th
division after deformation taking place.
Pyrometric cone equivalent:-
This is the resistance of the refractory material to soften during service temperature.
2
Take the composite sample of the refractory material in 150 micron size.Remove the
iron by a magnet.Make the PCE sample of a regular tetrahedron of base in 8 mm and
height in 25 mm by using a PCE mould with the help of water and dextrose as a
binder.
Place the sample on a refractory flake along with the standard cone(Ortan/Sekher
cone).Put the flake with the samples in a PCE furnace and raise the temperature.
Standard
Sample
PCE temperature is the temperature at which the sample bend and its tip just tough the
plane of the flake and can measure by a optical pyrometer. This is the comparison test
and can compare with the standard sample. ie. if the standard bends first and the
sample is intact
then the PCE value is + of the standard cone PCE number. If the sample bends first
and the standard is intact then the PCE value is minus of the standard cone number or
if both the sample and standard are bend simultaneously then the PCE value is the
same value of the standard cone number.
Cold Crushing Strength:-
This is the ratio of the breaking load to the area in cm 2 of the refractor materials. The
good refractory material should have high value of the cold crushing strength.
Make the sample of size of 75 mm3 by sample cutting machine.Remove the moisture
the moisture by putting them in a air oven.After air cooling measure the area of the
sample and place the sample in to the ccs machine with the cushion above and below
of the sample.Apply the load and note the crushing load in kg and calculate the CCS
value.
Crushing load
CCS kg/cm2 = kg/cm2
Area of cross section.
Permanent linear change:-
The expansion of the refractory during service temperature in percentage is called as
permanent linear change.
3
Cut the sample of size 125x40 mm by a sample cutting machine and try in an air oven
to remove the moisture. Measure the length of the specimen in mm. Place the sample
in a PLC furnace and switch on the furnace. soak the samples in the specified
temperature for the specified period. Allow the samples to cool in the furnace itself.
After cooling to the room temperature measure the final length of the specimens in the
same location and calculate the PLC value in %
Initial length – Final length
PLC% =. X 100
Initial length
War page:-
This is the bend of the refractory material. The good refractory material should free
from war page.
Place the war page gauge on the bigger area ie. On the surface of 230x115 mm2 of the
ladle brick and measure the bend/war page in mm.
4
P h y s i c a l:
Tensile test:-
This is the ratio of the maximum load per area of the cross section on the tensile test
piece.
Make the tensile sample as per IS-1608/latest.Measure the diameter of the sample and
make two dots apart 5 times of diameter of the test piece. Place the sample in to the
tensile testing machine and apply the load. Note the yield load and the maximum load
and measure the reduced diameter of the broken sample.Calculate the tensile
strength.The sampling frequency shall be one per cast for axles and 1 for 1000,1 for
500 and 1 foro 250 for Box-N,Carriage and loco wheels respectively.
Maximum load
Tensile strength = Kg/mm2
Area of cross section
Final length - Initial length
Elongation% =
(GL-5.64 root A0 ) Initial length
Initial area – Final area
Reduction area % = x 100
Initial area
Micro grain size:-
This is the number of grains per square inch at 100x.
Take the micro sample and grind wheel by a grinding machine. Use the emery papers
of various grades from rough to fine and while changing the next emery paper the
polishing direction should be perpendicular to the previous paper. Use the diamond
paste for final polishing .Clean well by alcohol/dish paper and etch the polished
specimen in 1:1 HCl.After drying check the micro grain size under metallurgical
microscope at 100 magnification. This is the comparison test and compare the grain
size with the standard chart as per IS-2853/latest.
5
Inclusion content:-
This also the comparison test and compare the inclusion rating with the stand chart as
per IS-1463/latest and report as follows. Carry out the test before etching.
Type Thin Thick
Sulphide(A type)
Alumina(B type)
Silicate(C type)
Oxide(D type)
Macro examination.
Take the vertical slice of wheel or axle. Mill it and heat in 1:1 HCl to the temperature
75 - 80 degree centigrade for about half an hour. Take out the etched sample clean by
water and dry. Examine with the naked eye or low magnifying glass of less than
10x.This also a comparison test and compare the macro piece with the standard chart
as per Astm-381/latest.The etched sample should free from crack, non-metallic
inclusion, flake, lap mark, segregation, pipe, pin holes, cavity and any other defects.
Hardness survey:
Take a vertical slice of one inch thickness, mill it and take the indentation by 10 mm
hardened steel ball in presence of 3000 kg load. Measure the diameter of the
indentation by a Brinel microscope and find out the value from the chart of clculate the
values by the following formulae.The sample frequency shall be one in 1000 for Box-
N,one in 500 for Carriage and one in 250 for loco wheels.The hardness values should
be in desending in nature from flange to the hub of the wheel.
2P
BHN =
3.14xD(10 – ( Root D2 - d2)
Where P - Load
D - Diameter of the indenter and
d - diameter of the indentation
Closer test:
This is the indication of the wheel contains a residual compressive stress after
quenching. Mark two points between 100 mm on the flange and the back rim. Take out
a slice of one thickness of a vertical slice by two radial saw cuts in a Do all machine
6
and after taking out the slice for the hardness survey measurer the distance between the
two points. The wheel should close and the minimum closer value should be +1 mm.
Closer test of wheel:
Puch 2 points apart 100mm on the flange
Takeout a wheel slice of 1” thickness by radial saw cut machine(Do all)
Take the final measurement and it shols be +1mm minium.
Hardness of wheel:
Mill both sides of the vertical wheel slice taken out during closer test.
Take BHN indentations by I” gap fron flange to hub of the wheel by a
BHN machine containing 10mm hardened steel ball&3000kgs load.
The hardness value should decreasing in trend from flange to the hub.
Axle.
Ultrasonic testing of axles.
Purposes :
To evaluate the quality of the axles by detecting the discontinuities which are harmful
to the axle service.
Principle:
Pass the ultrasonic sound in to the axle under test from one end face of better surface
finishing of 3.2 micron. The sound rays will penetrate through out the axle and after
reaching the opposite end the sound rays will reflect back t o the home position by the
reflection of the air medium.
Method - Pulse echo method
Equipment used - USD-15S,Khruatkrammer,German make or equivalent.
Normal probe - PZT typeof 20-26 mm diameter and 2 – 2.5 MHz
frequency
of Kruatkrammer,German make or eqivallent.
Low angle probe - Gun assembly contains 1.3,19.3&24.3 degree probes to
detect the the discontinuities in body,up to inner wheel
seat fillet and up to the outer wheel seat fillet
respectively.
Couplant - Grease dissolved in oil
Stage of inspection - Surface finish shall be better than 3.2 micron
7
Standardization:
406
Probe 25
381
Initial echo Back wall
Flaw echo (12.5%)
Place the normal probe just opposite to the 3.2 mm dia artifishal made flat bottom hole
and adjust the gain to get 12.% of the flaw height. Not the gain and is called as FBH
standard gain.
Standardization for Gun assembly:
Probe
6mm saw cut Gun assembly
Initial echo Flaw echo(75% height) Back
wall
8
Place the gun assembly on the standard axle containing 6 mm artifishal saw cut and
adjust the flaw height to 75% and note the gain.It is the standard gain for
Gunassembly scanning.
9
Fax No.0343-2546625
Kind attn to Shri.ChandrasekharRao,CMT,RWF Inspection cell
C/o. R & C Lab. /ASP.
Standardization for radial scanning(As per R-16/’95):
200
3.2
25±2
150
Initial echo Flaw echo(60%) back wall
Range = 250 mm
Place the probe exactly opposite to the artificial flaw of 3.2 mm diameter and adjust
the gain to get 60% flaw height and note the gain. This is called as FBH standard gain
for radial scanning of R-16 / ’95 axles.
10
Fax No.0343-2546625
Kind attn to Shri.ChandrasekharRao,CMT,RWF Inspection cell
C/o. R & C Lab. / ASP.
Standardization for radial scanning(As per R-43/’92):
260
3.2
25±2
150
Initial echo Flaw echo(60%) back wall
Range = 400 mm
Place the probe exactly opposite to the artificial flaw of 3.2 mm diameter and adjust
the gain to get 60% flaw height and note the gain. This is called as FBH standard gain
for radial scanning of R-43 / ’92 axles.
11
Fax No.0343-2546625
Kind attn to Shri.ChandrasekharRao,CMT,RWF Inspection cell
C/o. R & C Lab./ASP.
Standardization for End – End scanning: (As per R-16’95&R-43/’92)
406
Probe 25
381
3.2(At mid radius)
Initial echo Back wall
Flaw echo (12.5%)
Place the normal probe just opposite to the 3.2 mm dia artificial made flat bottom hole
and adjust the gain to get 12.5% of the flaw height. Note the gain and is called as FBH
standard gain.
(All dimensions are in mm)
12
Fax No.0343-2546625
Kind attn to Shri.ChandrasekharRao,CMT,RWF Inspection cell
C/o. R & C Lab./ASP.
Standardization for Gun assembly: (As per RWF)
Gun assembly
6mm saw cut Gun assembly
Initial echo Flaw echo(75% height) Back
wall
Place the gun assembly on the standard axle containing 6 mm depth artificial saw cut
and adjust the flaw height to 75% and note the gain.It is the standard gain for
Gunassembly scanning.
13
Fax No.0343-2546625
Kind attn to Shri.ChandrasekharRao,CMT,RWF Inspection cell
C/o. R & C Lab./ASP.
DAC blocks for drawing DAC curve: As per IRS specifications R-16/’95&R-43/’92)
Zone Length of DAC block in mm Diameter of FBH in mm
I 101.6
177.8
279.4
406.4
3.2
3.2
3.2
3.2,6.4(Use for II zone also
as a first block)
II 533.4
660.4
787.4
6.4
6.4
6.4,9.5(Use for III zone
also as a first block
II 914.4
1041.4
1168.4
9.5
9.5
3.2,6.4,9.5
14
Visual inspection:
Check the face, CTA, Journal, wheel seat and body of the axle visually by naked
eye/low magnifying lens etc. If the axle contains gouge mark, end crack of the defects
due to the RWF’s process make it as defective non-source(S).If the axle is getting
rejected ultrasonically made as UT rejected® and if contains inclusion crack of any
other defects due to the manufacturer of the bloom make it as defective Source(S) and
enter in LAN record.If the defect may go by further machining make it as others(O) or
if it is free from any defects carry out the ultrasonic testing.
Penetrability test:-
Clean the face of the axle and apply the couplant.Do the preliminary adjustments of
the UFD and scan with normal probe.If the wack wall at FBH gain is mere than 25%
further carry out the testing and the penetrability test is ok..If it is <25% mark it for
RHTMore than two RHT is not permitted and the axle is rejected.
Far end scanning:-
Clean the face of the axle and apply the couplant.Do the preliminary adjustments of
the UFD and scan with normal probe&observe any signal between initial and back
wall.If it is due to the shape/geometry of the axle it is ok.If it is due to flaw, reduce the
gain in the setting FBH gain and if it is more the 12.5% amplitude height it is cause for
rejection and enter in LAN as ut rejected®.
Testing by Gun assembly:-
Place the gun assembly on the axle face and rotate slowly at least twice in clock and
another twice in the anti clock directions and observed the ut screen. If there is no flaw
signal the axle is ok and if there is a flaw signal with more than 75% of the amplitude
height at FBH gain is a cause for the rejection.
Manual radial scanning:-
Do the preliminary adjustments and apply the couplant on the axle laterally. Scan and
if the axle is free from the flaw signal it is ok. Otherwise follow the following rejection
norms for the radial scanning of the axle.
a) Flaw signal with more than 60% at FBH gain and more than 2 probe length
on Journal & Wheel seat and more than three probe length on body is cause
for rejection.
b) If the distance between two isolated signals is lesser than 200 mm is a
cause for rejection.
c) More than three isolated signals throughout the axle is a cause for rejection.
d) Flaw signal with 60% of amplitude height provided the location is between
and mod-radius & surface f the axle is cause for rejection.
Manufacture of Box-N axle:
Billet cutting:-
Cut the bloom in 975 +/- 5 mm by saw/gas cutting carefully
Preheating in RHW:-
15
Charge the billets in the RHW and heat to 1150 – 1200 deg C for about 6 hours
Forging:-
Forge the preheated billets by long forging machine
End cutting:-
Remove sufficient discards by gas cutting
Number stamping:-
Stamp the serial number of the axle by automatic stamp punching machine in hot
condition
Intermediate cooling:
Allow the hot axle to cool to 200 - 250 deg. C through the intermediate cooling bed
Heat treatment:
Normalizing:-
Charge the cooled axles at 200 – 250 deg. C in to Normalizing furnace and heat to 840
- 860 deg C for about 6 hours.
Intermediate cooling:
Allow the normalized axles to cool to 200 deg. C through the intermediated cooling
bed.
Tempering:-
Charge the air cooled axles to 200 deg. C in to the Tempering furnace at the
temperature of 550 - 640 deg. C for about 8 hours 45 minutes.
Air cooling:-
After tempering allow the tempered axles to air cool for about 24 hours.
Lab. Test:
Take two samples of size 250x25x25 mm size from the center portion of the prolonged
journal portion of the heat treated axle and conduct all the required tests to conform
following requirements as per R-16-/1995.
Physical properties:-
Sl.No. Characteristics Requirements as per R-
16/’95
1 Yield strength N/mm2 Min. 320
2 Tensile strength N/mm2 550 650
3 Elongation% Min. 22
16
(Gl-5.65 root A0 ) Where, Ao - area of
cross section of test piece.
4 Micro grain size @ 100x Not coarser than ASTM
grain size No.5
5 Macro examination Should not reveal any
defects and central
segregation should be
better than C2
6 Micro structure Uniform fine pearlitic
structure
Chemical composition:-
Sl.No. Elements Requirements as per R-
16/’95
1 C% 0.37 + 0.03
- 0.00
2 Mn% 1.12 + 0.06
- 0.00
3 Si% 0.46 + 0.04
- 0.00
4 P% 0.04 + 0.005
- 0.000
5 S% 0.04 + 0.005
- 0.000
6 Cr% 0.3 + 0.05
- 0.00
7 Ni% 0.3 + 0.02
8 Cu% - 0.00
9 Mo% 0.05 + 0.00
- 0.00
10 V% 0.05 + 0.00
- 0.00
Machining of the axle:-
a. Cup turn,end mill and make the lathe center bore.
Number stamping:-
Punch the serial No. and Cast No. of the axle manually on the axle face.
Ultrasonic testing:-
Scan the axle ultrasonically thoroughly and if the axle is passing allow to further
machining by putting the UT stamp on the axle number face.
17
Further machining:-
b. Rough turn the axle
c. Semi finishing of the axle except body
d. Body finishing
e. Finishing of the axle except body
f. Drilling, tapping and recentering of the axle
g. Furnishing of wheel seat
h. Centreless grinding of journal, dust guard etc.
Magnetic particle testing of axle:-
Conduct the MPT of the axle and if it is passed allow the passed axle for pressing by
putting the MPT stamp on the axle face opposite to the UT stamp.
Magnetic Particle Testing of axle:(MPT)
Equipment used:
Magnaflux,USA make of DH 5455 model.
Current used:
Half wave DC for coil&Contact magnetization
AC for Demagnetisation
Current used for
Coil magnetization = 1200 Amps.
Contact magnetization = 1800 Amps.
Demagnetization = 3000 Amps.
Bath oil = MX-MG Carrier Oil-II supplied by M/s.ITW Signode,Hyderabad.
MPT Powder = Magnaflux-14A supplied by M/s.ITW Signode,Hydreabad.
Amount of powder per litre = 1.25 gram/litre.
Concentration of the bath = 0.2 - 0.30 ml/100 ml after half an hour.
Watt of the UV lamp = 100 watt.
Intensity of the UV lamp = 525 micro watt/centimeter square.
Principle:
Magnetize the axle under test.Magnetic force of lines will develop.Spray the bath containing containing
iron particle coated with flourescent material.If there is a defect,the magnetic force of lines will leak
i.e. leakage of magnetic flux arround the defect and attract more particle around the defect and can seen
under UV lamp.
Coil magnetization:
Place the coil over wheel seat and pass the current through the coil to develop longitudinal field.Spray the.
bath and after few seconds inspect under UV lamp to detect the verticle discontinuities.The discontinuity
will develop polority and will attract more powder arround the defect and can seen under UV lamp.If the defect
may go by re work mark for rework.
Contact magnetization:
Press the contact pad and pass the current through the axle to develop circular magnetic field to detect the
longitidinal discontinuities.Spray the bath and inspect under UV lamp as above.
Demagnetization:
Press the contact pad and pass the AC current through the axle to demagnetize the magnetized axle.The
residual magnetic field shall be plu or minus 5 gauss.
Imperfections not permisciple:
1. Any type of verticle,circumferential discontinuities any where on the axle not permitted.
2 Any type of discontinuities on the fillet not permitted.
18
Imperfection permiciple:
Journal:
Heat diagram of Box-N axle:
Heat diagram of BGD axle:
19
Iron - Carbon System
1600
Liquid
Delta iron
1539
Delta iron + Liquid
0.53%
0.08% Austenite Liquid
1490 +
Cemintite
Austenite+Liquid
1400
Liquid+
Austenite+ Austenite 1146 oC
Delta
T Austenite+Ferrite Austenite Cemintite
e 910 + +
m Aus+ Ledeburite Ledeburite
p 768 Cemin +
e tite Cemintite
r 727 oC
20
a oC
t 0.02%
u P
r e Pearlite
e a +
Ferrite r Transform- Cemintite
l ed Ledebu- +
Pearlite + i Pearl- rite + Ledeburite
Ferrite t ite + Cementite
e Fe3C
0 0.8 2 4.3 6.67
Steel Cast Iron
Hypo Hyper Hypo Hyper
Eutectoid Eutectoid Euectic Eutectic
Carbon% wt
Fe-C system is a graphic representation of various transformation of carbon % weight at various
temperatures.
Phases: Ferrite:- It is an interistial solid solution in which carbon in BCC iron .The maximum solubility is 0.02%
maximum at 227 degree centigrade. It exists from 910 degree centigrade to minus 273 degree centigrade.
Austenite: It is an interstitial solid solution of carbon in FCC iron. The maximum solibility is 2.1 % at 1146
degree centigrade.
Delta iron:
It is an interstitial solid solution of carbon in BCC iron. The maximum solibility is 0.08 % at 1400 degree centigrade.
It is from 1539 degree centigrade which is the melting point of iron to 1400 degree centigrade.
Pearlite:
This an alternative arrangement of parallel plates of ferrite and cemintite
Cemintite:
It is an intermetalic compound represented by the formula Fe3O4.the structure is orthorhombic and the number of
atom is 25% but the C weight % is 6.67.Hence after 6.67% of carbon the Fe-c system is not extended.
Transformations:
Iron-Carbon System:
21
The various transformations place in Fe-C system is as follows.
1.Feritectic reaction:
Reaction Delta iron + Liquid Gama iron
Structure BCC -- FCC
C% wt. 0.08 0.53 2.1
Liquid and delta irons react together and forms austenite at 1400 degree centigrade temperature.
2.Eutectic reaction:
Reaction
Liquid
Austenit
e + Cemintite
Structure -- FCC Ortorhombic
C% wt. 4.3 2.1 6.67
Liquid iron will become austenite and cemitite on cooling at 1146 degree centigrade temperature.
3.Eutectic reaction:
Reaction Austenite + Ferrrite + Cemintite
Structure FCC BCC
Orthorhombic
C% wt. 0.80 0.02 6.67
Critical temperatures:
These are the temperatures at which various transformations tking place and are as follows.
1.Gama iron will become ferrite and cemintite on cooling at 727 degree centigrate and represened
by the symbols A,c,r etc., On slow cooling Ac1=Acr=727 degree centigrade.
On normal cooling there is thermal hysterisis and Ac1>Acr.
2.The next higher is curie temperature of ferrite iron & represented by the symbol A2 and is 768
degree centigrade at which
frrrite will undergo magnetic transition from ferro to para magnetic stage.
3.The temperature corresponds to the phases Gama+ferrite/gama iron is A3 and it is steeper
degreses from 910 degree
centigrade to 727 degree centigrade.Unlike A1 this is function of carbon % weight.
4.The temperature corresponds to the phase Gama iron+cemintite/gama iron is ACM and is increased
from 727 to 1146 degree
centigrades.This also a function of carbon % weight.
5.The curie temperature of ferrite is A0 and is 210 degree centigrade.
Micro structure of steel:
22
1.Eutectiod steel:
The structure is pearlite and the chemical composition is '0.80% C weight. The amount of ferrite &
cementite can be calculated By lever rule and is as follows.
6.67 - 0.80
Ferrite% = x 100 =
88.3
6.67 - 0.02
0.80 - 0.02
Cementite= x 100 =
11.7
6.67 - 0.02
or
100 - 88.3 = 11.7%
2.Hypo eutectoid steel:
The chemistry is < 0.80 % c weight.For example in 0.2% C steel the amount of
consitituents in 0.2 % C weight are '0.80 - 0.2
Ferrite% = x 100 = 76.9
0.80 - 0.02
'0.20 - 0.02
Pearlite % =
x 100 = 23.1
'0.80 - 0.02
3.Hyper eutectic steel:
The chemistry is '0.80 - 2.1 % C weight.In 1.2% Carbon steel the amont of consistituents are ' 6.67 - 1.2 Pearlie % =
x 100 = 93.2 6.67 - 0.80 Cemintite = 100 - 93.2 = 6.8
Wheel defects:-
Defect Code Description
3 Off analysis
8 Low Brinell
9 Tramp elements
10 Crack&Checks
12 Ceramic-Metal-Refractory
13 Slag
15 Pin holes
16 Ultrasonic
23
20 Rabit ears(Sand expansion)
30 Off center hub cut
31 Wrong hub cut
32 Gough bore
33 Hole in bore
35 Goughed riser
38 Damaged stampimg
39 Unknown heat number
40 Gas hole in tread
42 Thin flange
43 Wrong mould machining
44 Insufficient spray
45 Hole in riser
46 Pocker
47 Eroded mould
48 Pin at apex
49 Mould shift
50 Poured short
51 LAP
52 Clusters of small holes on rim
53 Gas holes in rim
54 Hollow sprue
55 Shrinkage riser stubs
56 Hollow hub face
57 Swollen beads
58 Run out
59 Closed down wrong
60 Stopper broken
61 Run back
62 Mould inclusions
63 Defective tube
64 Porous sprue
65 Buckled pad
66 Hollow hub feeding
67 Defective core
68 Depressed pad
70 Dela processing
71 War page
72 Spoiled normalizing
73 Spoiled handling
90 Spoiled mounting
91 Spoiled grinding
92 Spoiled machining
93 Spoiled mechanical
94 Spoiled power
24
95 Spoiled electrical
96 Experimental
97 Obsolete
98 Missing
99 New design
121 Black, gray tube inclusion
122 Small,irregula,combined brown
123 Splatter of 122
124 Refractory
125 Defective tube
126 Unknown
128 Small red orange
129 Blowing tube
131 Slag on tread
135 Pin in slag
138 Furnace slag
139 Slag splatter
621 Spray
622 Asbestos
623 Rat tail(Seams in throat)
624 Graphite or sand
625 Spray or sand
626 Graphite
627 Fused sand
628 Raw sand
629 Sand splatter
25
Specifications:
Specn. Analysis H2 N2 Red.Ratio C% Mn% Si% S% P% S+P% Cr% Ni% Cu% Mo% V% UTS YS Min.
E%(GL= 5.65 root A0
GS @ 100x
Macro
R-16/95
LA 3 PPM Max.
70 PPM Max.
2-1/Ingot - Bloom 1.5-1/ Ingot-bloom provided 5-1/ ingot axle 3-1/ Ingot-axle 3-1/ Concast bloom-axle
0.37 Max.
1.12 Max.
0.46 Max.
0.04 Max.
0.04 Max.
0.07 Max.
0.3 Max.
0.3 Max.
0.3 Max.
0.05 Max.
0.05 Max.
550-650 N/ mm
2
320 N/ mm
2
22 % Min.
Not coarser than 5 @100x
Better
than
C2&No
any
other
defects
PA(Over LA the following shall be permitted)
-- -- 2-1/Ingot - Bloom 1.5-1/ Ingot-bloom provided 5-1/ ingot axle 3-1/ Ingot-axle 3-1/ Concast bloom-axle
+0.03 - 0
+0.06 - 0
+0.04 - 0
+0.005 - 0
+0.005 - 0
-- +0.05 -0
+0.05 -0
+0.02 -0
-- +0.02 -0
-do- -do- 22 -do- -do-
R-43/92
LA / Ctategory-A
2 PPM Max.
70 PPM Max.
2-1/Ingot - Bloom 3-1/ Ingot-axle 1.5-1/ Ingot-bloom provided 5-1/ ingot axle
0.40-0.55
0.60-0.90
0.15 Min.
0.05 Max.
0.045 Max.
-- -- -- -- -- -- 570-685 N/mm2
50% of UTS Min.
17-21 6-8 @100x
-do-
PA(Over LA the following shall be permitted)
-- -- 2-1/Ingot - Bloom 3-1/ Ingot-axle 1.5-1/ Ingot-bloom provided 5-1/ ingot axle
+/-0.03 Max.
+/-0.03 Max.
+0.0 -0.15
+0.005 +0.005 -- -- -- -- -- -- -do- -do- -do- -do- -do-
R-19(III) /1995
LA 3 PPM
70 PPM
-- 0.57-0.67
0.60-0.80
0.40 Max.
0.03 Max.
0.03 Max.
-- 0.15 Max.
0.25 Max.
-- 0.06 Max.
-- 930 N/mm2 Min./ Rim
50% of UTS Min.
4.5 Min. -- -do-
PA -- -- -- +0.03 –0.02
0.01 0 +0.005 - 0
+0.005 - 0
-- 0.05 0.05 -- +0.02 -- -- -- -- -- -do-
Specn. Analysis H2 N2 Red.Ratio C% Mn% Si% S% P% S+P% Cr% Ni% Cu% Mo% V% UTS YS Min.
E%(GL= 5.65 root A0
GS @ 100x
Macro
R-16/95
LA 3 PPM Max.
70 PPM Max.
2-1/Ingot - Bloom 1.5-1/ Ingot-bloom provided 5-1/ ingot axle 3-1/ Ingot-axle 3-1/ Concast bloom-axle
0.37 Max.
1.12 Max.
0.46 Max.
0.04 Max.
0.04 Max.
0.07 Max.
0.3 Max.
0.3 Max.
0.3 Max.
0.05 Max.
0.05 Max.
550-650 N/ mm
2
320 N/ mm
2
22 % Min.
Not coarser than 5 @100x
Better
than
C2&No
any
other
defects
PA(Over LA the following shall be permitted)
-- -- 2-1/Ingot - Bloom 1.5-1/ Ingot-bloom provided 5-1/ ingot axle 3-1/ Ingot-axle 3-1/ Concast bloom-axle
+0.03 - 0
+0.06 - 0
+0.04 - 0
+0.005 - 0
+0.005 - 0
-- +0.05 -0
+0.05 -0
+0.02 -0
-- +0.02 -0
-do- -do- 22 -do- -do-
R-43/92
LA / Ctategory-A
2 PPM Max.
70 PPM Max.
2-1/Ingot - Bloom 3-1/ Ingot-axle 1.5-1/ Ingot-bloom provided 5-1/ ingot axle
0.40-0.55
0.60-0.90
0.15 Min.
0.05 Max.
0.045 Max.
-- -- -- -- -- -- 570-685 N/mm2
50% of UTS Min.
17-21 6-8 @100x
-do-
PA(Over LA the following shall be permitted)
-- -- 2-1/Ingot - Bloom 3-1/ Ingot-axle 1.5-1/ Ingot-bloom provided 5-1/ ingot axle
+/-0.03 Max.
+/-0.03 Max.
+0.0 -0.15
+0.005 +0.005 -- -- -- -- -- -- -do- -do- -do- -do- -do-
R-19(III) /1995
LA 3 PPM
70 PPM
-- 0.57-0.67
0.60-0.80
0.40 Max.
0.03 Max.
0.03 Max.
-- 0.15 Max.
0.25 Max.
-- 0.06 Max.
-- 930 N/mm2 Min./ Rim
50% of UTS Min.
4.5 Min. -- -do-
PA -- -- -- +0.03 –0.02
0.01 0 +0.005 - 0
+0.005 - 0
-- 0.05 0.05 -- +0.02 -- -- -- -- -- -do-
Parts of the axle.
Body
Inner
W/s fillet
Wheel
seat
CTA
LCB
Face
Journal
Outer
w/s
fillet
Axle flow chart.
ON LINE ULTRASONIC TESTING OF CAST STEEL WHEELS MANUFACTURED
AT RWF
Introduction
All the cast wheels shall be ultrasonically tested with minimum of 6 transducers in two
directions (radially and axially) through rim section in accordance with IRS R-19/1993
(Part III). The Calibration reference standard and rejection level of each wheel design is
established by making test set-up wheel. Procedure for ultrasonic testing of cast steel
wheels are followed as laid down in the relevant specification.
Standardization of Ultrasonic testing system is carried out in the beginning of each shift
or whenever there is a break down or any change of component in on line system or
change in wheel design under process.
The custom built ultrasonic system is in compliment with the production process to detect
all possible casting defects in rim section of the wheel.
Ultrasonic scanning system
In casting of wheels by controlled pressure pouring technique, defects like shrinkage
porosity, gas holes etc., which occur during solidification within the rim section. In RWF
the ultrasonic testing methodology employed is automatic on line immersion technique in
water medium incorporating 6 transducers connected to a microprocessor based multi-
channel computer controlled scanning system.
Preheating
at RHF (1150
-1200)
Forging by
LFM(1100
-900)
Normalizing
(1150-1200
deg. C
Cooling
Billet cutting
by Gas/Saw
cutting)
Cooling Temp-
ering(550-
640)
CTA, LCB&End
Milling
Lab.
testing
Air
cooling
UT
Further
machining
MPT Assembly
28
Convergent beam Transducers of 2.25MHz & 5.0MHz frequency and 20 mm crystal
diameter are employed. Each transducer is identified as 1A, 2A, 3A, 1B, 2B & 3B.
Transducer 1A(2.25MHz) – is focused axially closer to tread for detecting defects
like gas holes below the front rim face and closer to tread.
Transducer 1B(2.25MHz) – is adjusted axially for detecting gas holes that may
occur below the front rim face farther away from tread and for cavities below the
sprue area.
Transducer 2A(5.0MHz) – is adjusted radially located below the tread for detecting
defects at the central line.
Transducer 2B(5.0MHz) – is focused radially located below the tread for detecting
defects at 1/8” away from the central line towards back rim.
Transducer 3A(5.0MHz) – is adjusted axially through front rim for detecting
defects at the central line.
Transducer 3B(5.0MHz) – is adjusted radially located below the tread for detecting
defects below the sprue.
All above 6 transducers are assembled in manipulator probe assembly immersed in tank
containing continuous flow of water.
Test Set Up
An ultrasonic standard test wheel of each design is fabricated by saw cutting the rim
cross-section and artificial reference holes of 1/8”dia ½” length are introduced at
shrinkage co-ordinates of the respective locations. Slices are welded back to match the
original profile of the wheel.
The above wheel is used as a standard-set-up-wheel for setting up probes so as to achieve
maximum response from the artificially drilled holes in the wheel rim.
Sensitivity of the equipment is set by using UT standard manufactured from the same
design wheel with 1/8” flat bottom hole, which will not be disturbed during the normal
testing process.
Testing System
RWF has employed microprocessor based computer controlled automatic on-line
ultrasonic system, which consists of basic ultrasonic machine, multiplxer, oscilloscope,
and computer with dedicated custom built software. The whole system is inter-linked
with PLC for communication and control. The Speed of the wheel is kept at 4 rpm and
minimum of 2 revolutions for a complete test cycle is ensured for every wheel. All the
testing parameters are displayed on screen and reference location is measured by the help
of an encoder. During the test, any signal from the defect location exceeding the set level
will be indicated on the screen as “REJECTED” and wheel stops automatically.
Inspectors ensure the defect & location manually and send the wheel to the scrap line.
29
Other wise, wheel automatically deemed as “PASSED” by the system and moves for
further processing. Ultrasonic status of the all the wheels tested is entered into the LAN
for record.
Equipment in use
Presently RWF is using 2 customized ultrasonic testing system designed and supplied by
M/s ULTRASONIC SCIENCES LIMITED
Unit 4-Spring Lakes Industrial Estate
GU-12 4 UH, Dead brook lane, Aldershot
Hampshire, ENGLAND
Tel: +44(0) 1252350550
Fax: +44(0) 1252350445
E-mail:info@ultrasonic-sciences.co.uk
Website:http://www.ultrasonic-sciences.co.uk
Ferro alloy calculation:
Points to be added x Tonnage of liquid metal x 10 Qty to be added= --------------------------------------------------------------
Efficiency of alloy
35 pts x 20 x 10 7000
For any alloy = -------------------------------------- = -------------
70% 70
= 100 kgs
100 kg of ferro
alloy to be added to raise 35 pts with 70 % efficiency
Conversely for 35 pts recovery (Recovery is 100%)
Accordingly recovery can be calculated.
30
Spray Mix – 100 lb. Batch – 35O Baume.
Ingredients:
CMC – 0.1% of the weight of fused Silica, 2 bags weighing 22.7 grams etch.
Veegum-T – 1.0% of the weight of Fused Silica, 3 bags weighing 152 grams each.
30 Micron Fuses Silica – 100 lbs (45,400 gms)
Formaldehyde – 120 ml (optional, depending on bacteria levels
Hot water – used with initial CMC or Veegum mixture, allows materials to go into solution more
readily.
Mixing Instructions:
a) To a clean mixing tank add 8 gallons of water. A permanent mark shall bemade on a rod
that relates 8 known gallons of water to a certain depth in the mixing tank. Turn mixer
on.
It is imperative that the mixing tank be thoroughly clean and completely empty.
Absolutely no spray mixture should remain in the tank from a previous batch.
b) Add 1 gallon of water to the specified mixing bucket. Turn waring blender on and add 1
bag (22.7 grams) of CMC powder slowly and uniformly to the water, while the agitator is
continuously in operation. Mix fore a minimum of 2 minutes, making sure that the CMC
is completely dissolved and free of lumps. Add this mixture to the larger mixing tank.
c) Repeat the above operation (b), using one gallon of water and 22.7 grams of CMC.
d) To the appropriate mixing bucket add 1 gallon of water and 1 bag (152 grams) of
Veegum-T, Mix for a minimum of 1 minute or until the Veegum-T is completely
dissolved and free of lumps.
e) Repeat the above operation (d), using one gallon of water and 1 bag (152 grams) of
Veegum T.
f) Repeat the above operation (d), using one gallon of water and 1 bag (152
grams) of Veegum-T.
g) After all the premixed CMC and Veegum-T has been added to the large mixing tank, wait
5 additional minutes before adding the fused silica. Each of the two 50 lb. Bags shall be
added separately and not until the prior bag has gone into solution. The lightening mixer
must be in operation at all times. Any paper from the bags that falls into the tank must be
removed.
h) After above solution has been mixed for 5 minutes, add 120 ml of
formaldehyde.
31
i) With the Baume instrument, measure the density of the spray
mixture. Adjust the consistency of the solution to 35O
- 40O Baume. (Baume may
be different from plant to plant depending non gun distance from mold and other
variables. This difference shall be verified through the Operating Department). If
the Baume is too high, add water slowly, and carefully bring down the Baume
within limits. If the Baume is too low, add Fused Silica slowly and carefully bring
up the Baume within limits. Determine the proper amount of water to add to the
mixing tank (in part (a)) in order to obtain a consistent Baume on the final spray
mixtures from batch to batch.
j) The Baume shall be recorded on the 302’s for the molds being sprayed.
6B. Mold Spray mix – 100 lb. Batch – 36O
Baume (Alternate method).
Ingredients:
CMC –0.1% OF THE WEIGHT OF fuses Silica, 1 bag weighing 45.4 grams.
Veegum – T – 1.0% of the weight of Fused Silica, 1 bag weighing 454 grams.
30 Micron Fuses Silica – 100 lbs. (45,400 gms).
Formaldehyde – 120 ml (optional depending on bacteria levels).
Hot water – used with initial CMC and Veegum Solution.
Mixing Instructions:
a) To a large clean mixing tank add 7 gallons of water. A permanent mark shall be made on
rod that relates 7 known gallons of water to a certain depth in the mixing tank. Turn
mixer on.
It is imperative that the mixing tank be thoroughly clean and completely empty.
Absolutely no spray mixtures should remain in the tank from a previous hatch.
a) Add 3 gallons of water to a mixing bucket (Detail-D) or sufficient water to bring
water level upto a known marker. Turn Waring Blender on and add 1 bag (45.4 grams) of
CMC powder slowly and uniformly to the water while the agitator is continuously in
operation. Mix for a minimum of 5 minutes making sure that the CMC is completely
dissolved and free of lumps. Add this mixture to the larger mixing tank.
a) To the mixing bucket add 3 gallons of water (or sufficient water to bring water
level upto a known marker) and add 1 bag (456 grams) of Veegum-T. Mix for a
minimum of 5 minutes or until the veegum-T is completely dissolved and free of lumps.
Again the mixer should be turning prior to adding the Veegum-T in a slow and uniform
manner. Add this mixture to the larger mixing tank.
a)
After all the premixed CMC and Veegum-T have been added to the large mixing tank,
wait 5 additional minutes before adding the Fused Silica. Each of the two 50 lb. Bags
shall be added separately and not until the prior bag has gone into solution. The lightning
mixer must be in operation at all times. Any paper from the bags that fall into the tank
must be removed.
32
a) After above solution has mixed for 5 minutes, add 120 ml of formaldehyde.
b) With Baume instrument, measure the density of the spray mixtures. Adjust
the consistency of the solution to 35O - 40
O Baume. (Baume may be different
from plant to plant depending on gun distance from mold and other variables.
This difference shall be verified through the Operating Department). If the
Baume is too high, add water slowly and carefully bring down the Baume
within limits. If the Baume is too low, add Fused Silica slowly and carefully
bring up the Baume within limits. Determine the proper amount of water to
add to the mixing tank (in part (a)) in order to obtain a consistent Baume on
the final spray mixture from batch to batch.
c) The Baume shall be recorded on the 302’s for the molds being sprayed.
7A. Mold Spray mix – 125 lb Batch – 36O Baume
CMC –0.1% OF THE WEIGHT OF fuses Silica, 2 bags
weighing 28.4 grams.
Veegum – T – 1.0% of the weight of Fused Silica, 3 bags
weighing 190.0 grams each.
30 Micron Fuses Silica – 125 lbs. (56,800 gms).
Formaldehyde – 150 ml (optional depending on bacteria
levels).
Hot water – used with initial CMC and Veegum Solution.
Mixing Instructions:
a) To a large clean mixing tank add 11.25gallons of water. A
permanent mark shall be made on rod that relates 11.25 known
gallons of water to a certain depth in the mixing tank. Turn mixer
on.
It is imperative that the mixing tank be thoroughly clean and completely
empty. Absolutely no spray mixtures should remain in the tank from a
previous hatch.
a) Add 1 gallons of water to a appropriate mixing bucket. Turn Waring Blender
on and add 1 bag (28.4 grams) of CMC powder slowly and uniformly to the
water while the agitator is continuously in operation. Mix for a minimum of 2
minutes making sure that the CMC is completely dissolved and free of lumps.
Add this mixture to the larger mixing tank.
c) Repeat the above operation (b), using 1 gallon of water and 1 bag (28.4 grams) of
CMC.
d) To the small mixing bucket add 1 gallons of water and add
1 bag ( 190.0 grams) of Veegum-T. Mix for a minimum of 1
33
minute or until the veegum-T is completely dissolved and free of
lumps. Again the mixer should be turning prior to adding the
Veegum-T in a slow and uniform manner. Add this mixture to the
larger mixing tank.
a) Repeat operation (d), using 1 gallon of water and 1 bag (190.0 grams) of
Veegum-T.
b) Repeat operation (d), using 1 gallon of water and 1 bag (190.0 grams) of
Veegum-T.
g) After all the premixed CMC and Veegum-T have
been added to the large mixing tank, wait 5 additional minutes
before adding the Fused Silica. Each of the two 50 lb. Bags shall
be added separately and not until the prior bag has gone into
solution. The lightning mixer must be in operation at all times.
Any paper from the bags that fall into the tank must be removed.
d) After above solution has mixed for 5 minutes, add 150 ml of formaldehyde.
e) With Baume instrument, measure the density of the spray mixtures. Adjust
the consistency of the solution to 35O - 40
O Baume. (Baume may be different
from plant to plant depending on gun distance from mold and other variables.
This difference shall be verified through the Operating Department). If the
Baume is too high, add water slowly and carefully bring down the Baume
within limits. If the Baume is too low, add Fused Silica slowly and carefully
bring up the Baume within limits. Determine the proper amount of water to
add to the mixing tank (in part (a)) in order to obtain a consistent Baume on
the final spray mixture from batch to batch.
f) The Baume shall be recorded on the 302’s for the molds being sprayed.
34
7B. Mold Spray mix – 125 lb Batch – 36O Baume
CMC –0.1% OF THE WEIGHT OF fuses Silica, 2 bags
weighing 56.8 grams.
Veegum – T – 1.0% of the weight of Fused Silica, 3 bags
weighing 568 grams each.
30 Micron Fuses Silica – 125 lbs. (56,800 gms).
Formaldehyde – 150 ml (optional depending on bacteria
levels).
Hot water – used with initial CMC and Veegum Solution.
Mixing Instructions:
a) To a large clean mixing tank add 10.25 gallons of water. A
permanent mark shall be made on rod that relates 10.25 known
gallons of water to a certain depth in the mixing tank. Turn mixer
on.
It is imperative that the mixing tank be thoroughly clean and completely
empty. Absolutely no spray mixtures should remain in the tank from a
previous hatch.
b) Add 1 gallons of water to a appropriate mixing bucket
(Detail-D) or sufficient water to bring water level upto a known
marker. Turn Waring Blender on and add 1 bag (56.8 grams) of
CMC powder slowly and uniformly to the water while the agitator
is continuously in operation. Mix for a minimum of 2 minutes
making sure that the CMC is completely dissolved and free of
lumps. Add this mixture to the larger mixing tank.
c) To the mixing bucket add 3 gallonss of water are sufficient
water to bring water level upto a known marker)and add 1 bag (
568.0 grams) of Veegum-T. Mix for a minimum of 5 minute or
until the veegum-T is completely dissolved and free of lumps.
Again the mixer should be turning prior to adding the Veegum-T in
a slow and uniform manner. Add this mixture to the larger mixing
tank.
d) After all the premixed CMC and Veegum-T have
been added to the large mixing tank, wait 5 additional minutes
before adding the Fused Silica. Each of the two 50 lb. Bags shall
be added separately and not until the prior bag has gone into
solution. The lightning mixer must be in operation at all times.
Any paper from the bags that fall into the tank must be removed.
e) After above solution has mixed for 5 minutes, add 150 ml of formaldehyde.
35
f) With Baume instrument, measure the density of the spray mixtures. Adjust the
consistency of the solution to 35O - 40
O Baume. (Baume may be different from plant to plant
depending on gun distance from mold and other variables. This difference shall be verified
through the Operating Department). If the Baume is too high, add water slowly and carefully
bring down the Baume within limits. If the Baume is too low, add Fused Silica slowly and
carefully bring up the Baume within limits. Determine the proper amount of water to add to the
mixing tank (in part (a)) in order to obtain a consistent Baume on the final spray mixture from
batch to batch.
g) The Baume shall be recorded on the 302’s for the molds being sprayed.
36
8A. Mold Spray mix – 200 lb Batch – 36O Baume
Ingredients:
CMC –0.1% OF THE WEIGHT OF fuses Silica, 4 bags weighing 22.7 grams.
Veegum – T – 1.0% of the weight of Fused Silica, 3 bags weighing 152 grams each.
30 Micron Fuses Silica – 4 bags weighing 50 lbs each or a total weight of 200 lbs. (90,800 gms).
Formaldehyde – 240 ml (optional depending on bacteria levels).
Hot water – used with initial CMC and Veegum Solution.
Mixing Instructions:
a) To a large clean mixing tank add 16 gallons of water. A permanent mark shall be made
on rod that relates 16 known gallons of water to a certain depth in the mixing tank. Turn mixer
on.
It is imperative that the mixing tank be thoroughly clean and completely empty. Absolutely no
spray mixtures should remain in the tank from a previous hatch.
b) Add 1 gallons of water to a appropriate mixing bucket. Turn Waring Blender on and add
1 bag (22.7 grams) of CMC powder slowly and uniformly to the water while the agitator is
continuously in operation. Mix for a minimum of 2 minutes making sure that the CMC is
completely dissolved and free of lumps. Add this mixture to the larger mixing tanks.
b) Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.
b) Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.
c) Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.
d) To the appropriate mixing bucket add 1 gallons of water and add 1 bag ( 152.0
grams) of Veegum-T. Mix for a minimum of 1 minute or until the veegum-T is
completely dissolved and free of lumps.
c) Repeat operation (f), using 1 gallon of water and 1 bag (152.0 grams) of
Veegum-T.
d) Repeat operation (d), using 1 gallon of water and 1 bag (152.0 grams) of
Veegum-T.
e) Repeat operation (d), using 1 gallon of water and 1 bag (152.0 grams) of
Veegum-T.
f) Repeat operation (d), using 1 gallon of water and 1 bag (152.0 grams) of
Veegum-T.
g) Repeat operation (d), using 1 gallon of water and 1 bag (152.0 grams) of
Veegum-T.
37
l) After all the premixed CMC and Veegum-T have
been added to the large mixing tank, wait 5 additional minutes
before adding the Fused Silica. Each of the two 50 lb. Bags shall
be added separately and not until the prior bag has gone into
solution. The lightning mixer must be in operation at all times.
Any paper from the bags that fall into the tank must be removed.
m) After above solution has mixed for 5 minutes, add
240 ml of formaldehyde.
n) With Baume instrument, measure the density of the
spray mixtures. Adjust the consistency of the solution to 35O - 40
O
Baume. (Baume may be different from plant to plant depending on
gun distance from mold and other variables. This difference shall
be verified through the Operating Department). If the Baume is too
high, add water slowly and carefully bring down the Baume within
limits. If the Baume is too low, add Fused Silica slowly and
carefully bring up the Baume within limits. Determine the proper
amount of water to add to the mixing tank (in part (a)) in order to
obtain a consistent Baume on the final spray mixture from batch to
batch.
o) The Baume shall be recorded on the 302’s for the molds being sprayed.
8B. Mold Spray mix – 200 lb Batch – 36O Baume(Alternate method)
Ingredients
CMC –0.1% OF THE WEIGHT OF fuses Silica, 4 bags
weighing 45.4 grams.
Veegum – T – 1.0% of the weight of Fused Silica, 2 bags
weighing 454 grams each.
30 Micron Fuses Silica – 4 bags weighing 50 lbs each or a total
weight of 200 lbs. (90,800 gms).
Formaldehyde – 240 ml (optional depending on bacteria
levels).
Hot water – used with initial CMC and Veegum Solution.
Mixing Instructions:
a) To a large clean mixing tank add 16 gallons of water. A
permanent mark shall be made on rod that relates 14 known gallons
of water to a certain depth in the mixing tank. Turn mixer on.
It is imperative that the mixing tank be thoroughly clean and completely
empty. Absolutely no spray mixtures should remain in the tank from a
previous hatch.
38
b) Add 3 gallons of water to a appropriate mixing bucket or
sufficient water to bring water level upto a known marker. Turn
Waring Blender on and add 1 bag (45.5 grams) of CMC powder
slowly and uniformly to the water while the agitator is continuously
in operation. Mix for a minimum of 5 minutes making sure that the
CMC is completely dissolved and free of lumps. Add this mixture
to the larger mixing tank.
a) Repeat the above operation (b), using 1 gallon of water and 45.5 grams of CMC.
d) To the mixing bucket add 3 gallons of water or sufficient
water to bring water level upto a known maker and add 1 bag (
454.0 grams) of Veegum-T. Mix for a minimum of 1 minute or
until the veegum-T is completely dissolved and free of lumps.
Again the mixer should be turning in a slow and uniform manner
prior to adding the Veegun-T. Add this mixture to the larger
mixing tank.
e) Repeat operation (f), using 1 gallon of water and 1 bag
(152.0 grams) of Veegum-T.
f) After all the premixed CMC and Veegum-T have been
added to the large mixing tank, wait 5 additional minutes before
adding the Fused Silica. Each of the two 50 lb. Bags shall be added
separately and not until the prior bag has gone into solution. The
lightning mixer must be in operation at all times. Any paper from
the bags that fall into the tank must be removed.
g) After above solution has mixed for 5 minutes, add 240 ml
of formaldehyde.
h) With Baume instrument, measure the density of the spray
mixtures. Adjust the consistency of the solution to 35O - 40
O
Baume. (Baume may be different from plant to plant depending on
gun distance from mold and other variables. This difference shall
be verified through the Operating Department). If the Baume is too
high, add water slowly and carefully bring down the Baume within
limits. If the Baume is too low, add Fused Silica slowly and
carefully bring up the Baume within limits. Determine the proper
amount of water to add to the mixing tank (in part (a)) in order to
obtain a consistent Baume on the final spray mixture from batch to
batch.
i) The Baume shall be recorded on the 302’s for the molds being sprayed.
39
2. Typical Mixes to Obtain 29-33 Baume with 15 Micron Min-U-Sil.
15
Micron
Min U
Sil
Total Quantities
ML
FORMAL
DEHYDE
Order of Addition
15
Micron
Min-U-
Sil
ML
Formal
Dehyde
Gals
Water
GRS
CMC
GRS
Veegum
Gals
Water
In
tank
GRS
CMC
+
1 Gal.
Water
GRS
Veegum
+ 1 Gal.
Water
10 2.0 4.54 45.6 12 0 4.54 45.6 10 12
20 3.8 0.09 91.2 24 1.8 9.08 91.2 20 24
30 5.7 13.6 136.8 36 3.7 13.62 136.8 30 36
40 7.6 18.16 182.4 48 5.6 18.16 182.4 40 48
50 0.5 22.70 228.0 60 6.5 22.70 114.0
114.0
50 60
60 11.4 27.24 273.6 72 8.4 27.24 136.8
136.8
60 72
70 13.3 31.78 319.2 84 9.3 15.89
15.89
159.6
159.6
70 84
80 15.2 36.32 364.8 96 11.2 18.16
18.16
182.4
182.4
80 96
90 17.1 40.86 410.4 108 12.1 20.43
20.43
136.8
136.8
136.8
90 108
100 19.0 45.40 456.0 120 14.0 22.70
22.70
152.0
152.0
152.0
100 120
110 20.9 49.94 501.6 132 15.9 24.97
24.97
167.2
167.2
167.2
110 1332
120 22.8 54.48 547.2 144 17.8 27.24
27.24
182.4
182.4
182.4
120 144
130 24.7 59.02 592.8 156 19.7 29.51
29.51
197.6
197.6
197.6
130 156
140 26.6 63.56 638.4 168 19.6 21.19
21.19
21.19
159.6
159.6
159.6
140 168
150 28.5 68.10 684.0 180 21.5 22.70
22.70
22.70
171.0
171.0
171.0
171.0
150 180
160 30.4 72.64 729.0 192 23.4 24.21
24.21
24.21
182.4
182.4
182.4
182.4
160 192
D. MIXING EQUIPMENT
1. Mixer – Mixing Equipment Co., Inc., C/o Fuente and Webster, 549 West Randolph
Street, Chicago, Illinois.
Model S-1,1/3 H.P. “Lightning” Mixer 110 Volt with 36” long # 304 stainless shaft
and two # 304 stainless steel 4” – 3 blade propellers.
40
2. Mixer Tank and Fixtures. Chicago Carb-O-Tank Co.,
746 West Fullerton, Chicago, Illinois
1 – 60 gallon type “H” 304 stainless steel tank complete with three 16” legs
1 – ¾” female outlet
1 – figure 11 brass N.P. faucet ¾”
1 – SS bracket (Portable agitator bracket for use with “Lightning” S-1 ,Mixer)
1 – SS cover slotted for “Lightning” S-1 – 1/3 H.P. Mixer
3. Blender Mixer. Master Elect Service Co., 835 West Washington Blvd., Chicago,
Illinois
Warning Mixer 1 gallon size, Part 004180 Alternate – 3 gallon mixing bucket –
Griffin Drawing E-606. 3-1, Detail-D
41
Heat treatment of axle:
The process involving heating&cooling to egt the desired properties suitable for
serviceby changing the structure,composition etc.
Stages of heat treament:
1. Heating to the required temperature
2. Holding(Soaking) at this temperature for a period of time to attain
uniform temperature throughout the section.
3. Cooling the steel at specified rate.
Principle of heat treatment
Normalizing:
It is the process of heating the steel to above the upper critical temperature followed by cooling in
air.
Normalizing
Austenite
910
Temperature
O C 723
Ferrite + Pearlite +
Pearlite Cemintite
0.8 2 C% wt
Purpose:
1. To relieve the internal stress
2. To refine the grain structure
Existing structure and
properties of steel Existing
structure and
properties of steel
Tempering
Normalizing
Air
cooling
Quenching
42
3. To improve the machinability
4. To improve strength&toughness
Temperature&time of NF:
Zones Temperature in o C Time in hrs(Cycle time x capacity
of the furnace) Required Set
Pre heating 840 - 860 850 2
Main heating 840-870 855 2
Soaking 850-880 865 2
Tempering:
Process of heating the axle to a temperature below lower critical temperature followed by air
cooling.
Purpose:
1. To reduce the thermal stress
2. To stabilize the structure of the axle
3. To reduce the brittleness and
4. To increase the toughness&ductibility.
Austenite
910
Temperature
O C 723
640 Tempering 550
0.8 2 C% wt
Temperature&time of TF:
Zones Temperature in o C Time (Cycle time x capacity of the
furnace) Required Set
Pre heating 550-640 610 2 hrs 55 min.
Main heating 610-640 610 2 hrs 55 min.
43
Soaking 610-640 610 2 hrs 55 min
Quenching:
The process of heating the axles to austenite phase followed by sudden cooling in polymer
quenchant which is echo friendly for about half an hour.
Purpose of hardening followed by tempering :
1. To develop high hardness, wear resistance and
2. To improve the strength and toughness
Austenite
Hardnening 910
Temperature
O C 723
640 550
0.8 2 C% wt
44
Suspended Particulate Matter from Duct:
i. Take the initial weight of the moisture free thimble in gm - 1.5210 gm
ii. Measure the stack pressure(h) mm H2O - 2.06 mm H
2O
iii. Measure the Stack temperature(Ts) in kelvin - 77 + 273 = 350 oC
velocity:
C = Pitet tube constant x Root of h x Ts m/sec. - 0.2022x 2.06 x350
iv. Select the nozzle (An) = 5.43 m/sec
Flow rate:
Qm = V x A x 60 x 1000 LPM - 5.43 x 60x1000 x3.165x10-5
10.31 LPM / ¼” Nozzle
- 5.43 x 60 x 1000 x7.123x10-5
- 23.21 LPM / 3/8” Nozzle
- 5.43x60x1000x7.917x10-6
- 2.58 LPM / 1/8” Nozzle
After Normalization flow rate:
298 298
Qn = Qm x LPM - 23.21x
TS 350
- 19.76 LPM
v. Collect the sample of 1000 litres min.
1000 1000
Sampling time = Min. -
Qn 19.76
- 50 Min.
vi. Measure the ambient temperature(Ta) in o K - 31+273=304
oK
vii. Measure the meter pressure mm - 20 mm Hg
viii. Calculate the volume of the sample collected
Vs = Qn x Time of sampling liter - 19.76x50=988 lit
ix. Actual volume of sample collected:
Vsx (750-Pm) x 298 19.76x(750-20)x298
Vn = -
760 x Ta 760 x 304
- 18.61 x 50=930.5 Litre at STP
x. Take the final weight of the thimble - 1.5413gm
Wt of dust =Fwt-Iwt - 1.5413-1.5210
- 0.0203 gm
Wt of dust 0.0203
SPM = x 106 Mg/Nm
3 - x10
6
Vs 930.5
45
- 21.8121.82 Mg/Nm3
Measurement of SPM of ambient air quality:
a) Take the initial weight of the moisture free filter paper in gm
b) Place the paper on the air sampler,set the time for 24 hours and switch on.
c) Note the flow rate in M3 per min.
d) Calculate the volume of air sample(V) m3/Min
V = Flow rate x Time in hours(24 hrs)
e) Take the final weight of the filter paper in gm
Wt of dust
SPM = x 106 µm / m
3
V
Eg)
FWt = 4.1970 gm
IWt = 2.8627 gm
Wt of the dust = 1.3343 gm
Flow rate = 1.435 m3 / min.
Tsampling = 24 x 60 Min.
V = 1.435 x 24 x 60 M3
1.3343
SPM = x 106
1.435 x 24 x 60
SPM = 645.71 µm / m3
46
Manufacturing of Wheel:
Furnace used:
High power basic direct electric arc furnace.The charge is melted by the heat produced by the arc
by passing high power electric current through the graphite electrodes.The charge is loaded as
heavy,medium&light scraps in bottom,middle&top of the furnace respectively.
Charge:
The raw material contains axle end cuts, risers, wheel cuts, medium scraps like sleeper, steel
plate,rods,buffes,spikes,keys etc.,borings,shereded scraps etc.The weight od each in the buckect
is as follows.
Sl.No. Type of scraps Number of magnets Weight in MT
approximately
1 Axle end cuts 2 2.5
2 Wheel risers 3 4 – 4.5
3 Wheel cuts 3 6
4 Medium scraps 5 - 7 4
5 Borings 2 - 3 2
6 Shredded scraps 2 2
7 Lime stone / Calcined lime -- 1.7 / 1.25
Melting:
The scrap is melted under a basic oxidizing slag consisting of lime stone and mill scales
providing cutting os scrap / collapses of bridges by O2 lancing..Consequently the Si,Mn&P
present are observed in to the basic oxidizing slag(Black) and when the process is completed,the
slag is completely removed without drain of steel melt.Take sample and send to spectro for
analysis. The oxidation reaction reactions are:
2FeO + Si = SiO2
+ 2Fe
FeO + Mn = MnO
FeO + SiO2 = FeO.SiO
2
MnO + SiO2 = MnO.SiO
2
5FeO + 2P = 5Fe + P2O5
3FeO + P2O5 = (FeO)3.P2O5
(FeO)3.P2O5 + 3CaO = 3FeO + (CaO)3 . P2O5
=
In the next stage new slag is formed by adding reducing slag mixture to deoxidize the bath.
Deozidation occurs due to the unoxidized Mn left during the first stage.Lime reacts with C to
form CaS which will further deoxidize and fix the S as CaS.The reactions are:
FeO + Mn = Fe + MnO
47
3C + CaO = CaC2 + CO
3FeO + CaC2 = 3Fe + CaO + 2CO
3MnO + CaC2 = 3Mn + CaO + 2CO
Sulphur present in the steel as FeS&MnS.and eliminated in the following way.
3FeS + CaC2 + 2CaO = 3Fe + 2CO + 3CaS
3MnS + CaC2 + 2 CaO = 3Mn + 2CO + 3CaS
FeS + C + CaO = Fe + CO + CaS
MnS + C + CaO = Mn + CO + CaS
CaS is insoluble in steel and will join with slag(White) and CO will maintain reducing
atmosphere in the furnace.Add Fe-Mn/Si-Mn to pick up the Mn containt in the bath(0.35 -
0.45%).Decarboration/recorporation may done by O2 lancing/by adding graphite powder as per
the spectr sample result.Stir the bath and maintain the temperature as 1640 – 1650 oC and take the
pre tap sample.After stirring the bath again take the 2nd
pretap sample within 2 -3 minutes.Raise
the temperature to 1680 - 1740 and tap the metal bath by opening the tap hole through the spout
in to the pre heated ladle containing calculated quantity of Graphite powder,Ferro-Silicon,Ferro-
Manganese/Silico-Manganese as per the spectro sample result.
Transfer the ladle with the molten metal in to the slaggoff station and remove the slag from the
center by slag coated metallic rabble through the lip of the ladle.Take slagoff sample for spectro
analysis and transfer the mladle in to John-mohr pressure pit.Measure the temperature by the TC
tip and when the temperature is 1620 oC add Al star of weight 450 gms each in to the bottom of
the ladle with the help of metallic rod to kill the steel.Take samples for ladle anslysis & H2&N2
measurement by spectro&Leco gas determinater respectively.
Casting:
Start the casting at 1610 - 1520 oC by bottom pressure pouring technique after closing the
pressure pit by the lid containing preheated ceramic pouring tube at its center by using graphite
mould(Assembled Cope&Drag moulds).When the molten metal touch the probe inserted in one
of the riser the pressure will drop and simultaneously the clay graphite stopper head will close the
entrance of the molten metal to prevent the run back. Add sufficient quantity of rice hull to
prevent the dropping of temperature and transfer the mould for solidification.
Splitting:
After calculated time(10-12 Min.)split the mould using the split grain.If dropping of metal is
observed increase the solidification time of reduce the solidification time if the risers are not
fallen during the splitting.Pass the hot wheels through the hot wheel kiln foe further hot
processing.
Sprue Wash:
Wash the protruded sprue by copper cotted electrode of one inch thichickness by using the
current of 1200-1800 Amps and minimum temperature of the sprue wash shall be of 380 oC to
prevent the sprue crack formation.
Number stamping:
Stamp the correct number of the heat on the back hub face by automatic number stamping
maching.
Hub cutting:
Make the hub bore by oxi-acetylene flame by using required pressure.
Heat treatment:
48
The process involving heating&cooling to egt the desired properties suitable for
serviceby changing the structure,composition etc.
Stages of heat treament:
4. Heating to the required temperature
5. Holding(Soaking) at this temperature for a period of time to attain
uniform temperature throughout the section.
6. Cooling the steel at specified rate.
Heat
Principle of heat treatment
Normalizing:
It is the process of heating the steel to above the upper critical temperature followed by cooling in
air.
Normalizing
Austenite
910
Temperature
O C 723
Ferrite + Pearlite +
Pearlite Cemintite
0.8 2 C% wt
Purpose:
5. To relieve the internal stress
6. To refine the grain structure
7. To improve the machinability
8. To improve strength&toughness
Existing structure and
properties are wiped out.Metal is now in a
condition to receive
new structure.
Existing
structure and
properties of steel
Tempering
Normalizing
Hub
cooling
Quenching
Air cooling
49
Temperature&time of NF:
Zones Temperature in o C Time in hrs(Cycle time x capacity
of the furnace) Required Set
Pre heating 840 - 860 850 2
Main heating 840-870 855 2
Soaking 850-880 865 2
Quenching:
The process of heating the Wheels to austenite phase followed by sudden cooling of rim by
water for about 4 - 4.5 min.
Purpose of hardening followed by tempering :
1. To develop high hardness, wear resistance and
2. To improve the strength and toughness
Austenite
Hardnening 910
Temperature
O C 723
640 550
0.8 2 C% wt
Tempering:
Process of heating the axle to a temperature below lower critical temperature followed by air
cooling.
Purpose:
5. To reduce the thermal stress
6. To stabilize the structure of the axle
7. To reduce the brittleness and
8. To increase the toughness&ductibility.
50
Austenite
910
Temperature
O C 723
640 Tempering 550
0.8 2 C% wt
Temperature&time of TF:
Zones Temperature in o C Time (Cycle time x capacity of the
furnace) Required Set
Pre heating 550-640 610 2 hrs 55 min.
Main heating 610-640 610 2 hrs 55 min.
Soaking 610-640 610 2 hrs 55 min
Hub cooling:
Cool the hub by the mixture of air&water for about 2.5 minutes.
Air cooling:
After complition of the heat treatment allow the wheels to air cool.
Apex gring;
Remove pins on the apex of the wheel by apex grinding machine about one full rotation.
Steel shot blasting;
Remove oil,crease,dirt,sand grains,spray particles and othe inclusions by steel shot blasting in a
closed chamber.
Magnaglow:
Do visual inspection followed by spraying the magnaglow bath on the magnetized wheel and
inspect und UV lamp.If free from any defects stock the wheel as first line stock otherwise send
the wheel containing defects to the grinding line and reinspect.
Ultrasonic testing:
Evaluate the quality of the rim portion of the wheel by detecting the discontinuities which are
harmful to service by automatic immersion technique in a water tank by radially & axially by
using 5&2 MHz convergent beam probes of six numbers respectively(3 for axile&other 3 for
radial).The wheel containg 3.2 diameter flaw ore shall be the cause for rejection.
51
Brinel Hardness testing:
Remove the scale on the front rim by automatic grinding machine and measure the BHN by
giving indentation by 10 mm hardened steel ball with the load 30000 kgs.
Warpage:
Check the warpage of the wheel on the drag side to prevent the derailment of the wheel.
Wheel peening:
Peen the wheel in a closed chamber by steel shots of SAE-550 grade or equivalent to improve the
fatigue strength of the wheel,to weldup the HLCs on the surface,distribute the locked up strees
uniformely through the wheel.
Hub bore:
Make the hub bore to the required diameter by Hub borer.
Final inspection:
Measure all dimensions of the wheels,rotundity,circumference and others by using suitable
measuring gauges and record the weight of the stocked wheel also.
Heat treatment of wheel:
The process involving heating&cooling to egt the desired properties suitable for
serviceby changing the structure,composition etc.
Stages of heat treament:
7. Heating to the required temperature
8. Holding(Soaking) at this temperature for a period of time to attain
uniform temperature throughout the section.
9. Cooling the steel at specified rate.
Heat
Principle of heat treatment
Normalizing:
Existing structure and properties are wiped
out.Metal is now in a
condition to receive
new structure.
Existing structure and
properties of steel
Tempering
Normalizing
Hub
cooling
Quenching
Air cooling
52
It is the process of heating the steel to above the upper critical temperature followed by cooling in
air.
Normalizing
Austenite
910
Temperature
O C 723
Ferrite + Pearlite +
Pearlite Cemintite
0.8 2 C% wt
Purpose:
9. To relieve the internal stress
10. To refine the grain structure
11. To improve the machinability
12. To improve strength&toughness
Temperature&time of NF:
Zones Temperature in o C Time in hrs(Cycle time x capacity
of the furnace) Required Set
Pre heating 840 - 860 850 2
Main heating 840-870 855 2
Soaking 850-880 865 2
Quenching:
The process of heating the Wheels to austenite phase followed by sudden cooling of rim by
water for about 4 - 4.5 min.
Purpose of hardening followed by tempering :
3. To develop high hardness, wear resistance and
4. To improve the strength and toughness
Austenite
Hardnening 910
Temperature
53
O C 723
640 550
0.8 2 C% wt
Tempering:
Process of heating the axle to a temperature below lower critical temperature followed by air
cooling.
Purpose:
9. To reduce the thermal stress
10. To stabilize the structure of the axle
11. To reduce the brittleness and
12. To increase the toughness&ductibility.
Austenite
910
Temperature
O C 723
640 Tempering 550
0.8 2 C% wt
Temperature&time of TF:
Zones Temperature in o C Time (Cycle time x capacity of the
furnace) Required Set
Pre heating 550-640 610 2 hrs 55 min.
Main heating 610-640 610 2 hrs 55 min.
Soaking 610-640 610 2 hrs 55 min
54
Hub cooling:
Cool the hub by the mixture of air&water for about 2.5 minutes.
Air cooling:
After complition of the heat treatment allow the wheels to air cool.
Preparation of coated sand:
55
Poring rate:
Fast pouring rate:
The flow of molten metal from the ladle in to the clay graphite head through ceramic pouring
tube is cast fast pouring rate.
Controlled pouring rate:
The flow of molten metal from the clay graphite stopper head through the wheel profile in to the
probe sensor in the riser is called as controlled flow rate.
The Pouring rate is given by the formula
Time
Pouring rate = Sec / PSI and can be read from the Anger-Gein chart
Pressure
plotted by time in second in Y axis and pressure in PSI in X axis.The X axis is calibrated as one
division is one PSI and the time in Y axis is 2.5 minutes.It shall be 2.25 – 1.25 Sec / PSI.
Eg)
The graph for the following values of time&pressure is as follows.
Time in seconds Pressure in Pounds per Square Inch
2.5 1.6
5 3.2
7.5 4.8
10 6
10
Pouring rate =
6
= 1.67 Sec / PSI.
Flow rate diagram
0
2
4
6
8
10
12
1.6 3.2 4.8 6
Pressure in PSI
Time in Sec.
56
Effect of pouring rate during wheel casting:
High pouring rate:
Porosity,gas holes,pin holes,cavity may form in the rim and below sprue portions
If the temperature is low flow rate may sufficiently increase to prevent the cold defects
Low pouring rate:
Low pouring rate may leads to cold defects like LAP
If the pouring temperature is high then low pouring rate is pemitted
If the bath temperature is low pouring rate may lead to cold defects.
Use of graphite moulds for wheel casting:
It has sufficient permeability
It has high thermal shock
It is easly machinable
It may re use after casting of one wheel for further casting
It has low thermal expansion
It has low linearity of coefficient
It has low ash content
It is less volatile
The chemical reaction between it and the molten metal bath is negligible
After casting easily cleanable without damage for further use
This is non-destructive mould
Less heat / thermal loss
The spray solution will easily adhere on the surface
It has sufficient strength.
It has high electric resistance
Repairable by machining
Sand testing:
GFN determination:
Take 100 gms of washed,dried and any other foreign material free sand and poured in the top of
the clean pre weighed test sieve series contains 600,425,300,212,150,106,75,53 micron sieves
and pan from top to bottom.Shake well for about 5 minutes by the sieve shaker motor and take
the final weight.Findout the % of the retention in each sieves and find out the GFN of the sand as
follows
Sieve size Initial
weight of
the sieve
Final
weight of
the seieve
Weight of
the
retention
% of the
retention
Factor Product
600 20
425 30
300 40
212 50
150 70
100 100
57
75 140
53 200
Pan 270
Total
Weight of the product
GFN = AFS.
Retention
Stick point determination(SP):
Spred thin layer of coated sand using metal feeder on the stick point apparatus.After one minute
brush out the un-sticking sand by camel hair brush to the point where sand has stuck to the bar
from the lower gradient side.Immediately measure the temperature by using the thermocouple at
the point where the sand has stuck.
Determination of CTS:
Make the test samples by pouring the coated sand on the brequtte shape on the bottom of the
heater at 232+/- 5 oC using aluminium scoop.flatten immediately and place the top heater on the
leveled surface.Soak for four minutes and remove the heater.After air cooling find out the CTS
value from the outermost scale(with the help of the movable magnet).Average of six samples will
be the CTS value of the coated sand.
Determination of HTS:
Pour the sample on the slot of brequtte shape of the bottom of the heater,flatten and immediately
place the heater overit.Bake 4 mintes and apply the load and read out the HTS value after
breaking the sample in hot condition.Average of the two samples will be the HTS value of the
coated sand.
58
Estimation of SiO2(Ram. mass):
Take 0.5 gm of dry sample in a beaker add 50 ml of 1:1 HCL and bake. It completelyExtract with
1;1 Hcl and wash thoroughly.Warm,cool and filter through 41 No. fiter paper.Take the ppt in a Pt
crucible ,chara and heat to 950 oC for about 30 minutes.9Filterate for the determination of
CaO&MgO)
Cool,moisten with conc.H2SO4 and add sufficient quantity of HF and evaporate on a hot
plate.Heat to 950 o c for 15 min,cool and weigh.
Wt before HFT - After HFT
SiO2 = x 100
Wt of the sample taken
Estimation of CaO:
Makeup the above filterate in to 250 ml in a SM flak.Pipette out 25 ml in a conical flask,add 10
ml NaOH(10 N).Make up the volume in to 50 ml,add 0.2 - 0.4 gm of P&R indicator & titrate Vs
0.02M EDTA soltion(7.44 gms in one litre of water).The end point is the appearance of the violet
blue colour.Note the volume of EDTA.
Vol. of EDTA consumed x 0.11216
CaO =
Wt of the aliquot taken
Estimation of MgO:
Pipette out 25 ml in a conical flask,add 30 of water and 25ml of buffer(68 gm of NH4Cl+570 ml
of Conc. NH in 1 litre) solution and few drops of EPT(0.5 gm EPTand 5 gm Hydroxlamine Hcl I
1 litre) indicator.Titrate Vs 0.02M EDTA till the colour changes from wine-red to blue.Note the
volume of EDTA consumed.
Vol. of EDTA consumed - Vol. of EDTA consumed for CaO
MgO = x 0.08062
Wt of the aliquot taken
Determination of Fe2O3:
Pipette out 50 ml of the filtrate obtained after filtration of Silica.Add 5 gm of NH4Cl,2 drops of
methyl orange(0.5gm in 1 litre) in and add NH4OH till the colour changes to
yellow.Warm&cool the solution and filtrate through 41 No. filter paper. Wash the ppt with hot
water and dissolve it in 50 ml of 1:1 Hcl and boil the solution.Add staneous chloride(6gm in
40ml Conc.Hcl&60ml dis.water,add few pieces of granulated tin and stored in amber coloured
bottle). till the soloution become colourless.Cool rapidely to room temperature.Add 10 ml of
stauraed mercuric chloride till the formation of silky white ppt.Add 20 ml of acid
mixture(Conc.Phosphoric acid&75ml Conc.Sulphuric acis in 350ml water),2-3 drops of BDAS
indicator(0.2-0.3gm in 100ml dis.water&stored in amber coloured bottle) and titrate Vs 0.01 N
Potassium dichromate solution(0.49gm in 1 litre) till the appearance of violet colour.
Vol. Of K2Cr2O7 consumed
Fe2O3% = x 7.984
Wt of the aliquot taken
59
Determination of Al2O3 in HA70% bricks:
Take 0.2-0.3gm sample and fuse with the fusion mixture at 950 deg. C & extract with 1:1
Hcl..Fllter through 41 No. filter paper and make it in to 250 ml in a SM flask.Transfer 25ml of
the aliquot and add sufficient amount of 0.01M EDTA (1 ml = 1.25gm of alumina)Add 2-3
drops of methyl orange and dilute with NH4OH(1:10) drop wise till the colour change to
yellow.Add 5ml acetate sodium acetate buffer(2ml acetic acid&21.5gm sodium acetate in 1 litre
of dis. Water-PH
–5.2),25ml water and heat toboilingfor 5 minutes.Cool and add 5-6 ml of xynol
orange indicator(0.1gm in 100ml dis. Water with 2 drops of 1:1 HCl) and titrate against standard
Zinc Acetate solution till the colour changes from yellow to orange or pink.Add 10ml of
ammonium fluoride solution and heat to boiling for 5 minutes.Cool and add 5ml buffer and 5-6
drops of zylenol orange indicator and titrate against standard Zinc Acetate solution till the colour
changes from yellow to pink.
Vol. of ZnAc consumed x 1.25
Al2O3 = x 100
Wt of aliquot
Alumina in Fe-Si:
Take 2.5gm in a Pt crucible and dissolve in 1:2 HF + HNO3 acid mixture till the samples
dsolved.Add 5ml of 50% Conc.HCl & fume till dense fumes evolved.Extract with 50ml of water
in 250ml beaker.Add 5ml of conc.hcl,boil then add 10gm of NH4cl,boil,cool and add NH2oH
and again boil till faint smell of NH3 persists.Filter through 41 No. filter paper,wash with hot
water and transfer the ppt in to 250ml beaker.Add 15ml conc.HNO3 +15ml conc.perchloric
acid.Fume to syrupy state with beaker covered with watch glass.Cool,add a drop of hcl,dilute to
20ml,boil and add50_60ml of 10% NaOH solution,boil on low heat,cool,filter through 41 filter
paper.Wash with hot water,collect the filtrate in to beaker,Add xynol orange indicator.Add hcl till
it turns from blue to yellow.Cool,make upto 250ml.Take an aloquot of 100ml,add 20ml of
0.01MEDTA,neutralize with 5% NaOH.Then add 5-10ml of acetate buffer.Boilfor
10minutes,cool,add xynol orange buffer and titrate against 0.01 M Zinc sulphate.
Carryout the blank with the same amount of EDTA and other reagents used above.
(Vol. of Zn Ac consumed for blank-Vol. of Zn Ac consumed for sample)
Al% = x 0.027
Wt of sample in the aliquot
Estimation of Silicon in Fe-Mn:
Take 1gm sample and dissolve in 30% conc.Nitric acid in a hot plate.Dry&bake for 1 hr at 100-
110 deg.C.Redissolve the baked mass in 40ml conc.Hcl by warming and dilute to 150ml with hot
water.Allow to settle and filter through 40 filter paper,wash 10-12 times alternatively with hot
1:20 Hcl and hot water.Ignite the ppt at 950 deg. C for about 30 minutes,cool and weigh.
60
Wt of silica obtained
Si = x 46.72
Wt of sample taken in gm.
Estimation of Mn:Take the filtrate obtained after removal of silica in a 500 ml conical flask and
treat with 10ml conc.Sulphuric acid and evaporate to fumes.Cool&dilute in to 100m.Boil until all
salts get dissolved.Make up in to 500ml.Pipetted out 25ml,add small amount of Zinc Oxide
emulsion till the liquid suddenly coagulates.Dilute to 200ml,boil and add 2-3 drops of conc.nitric
acid and titrate vs 0.1 N KmnO4 solution in hot condition itself.Agitate the contents in a conical
flask after each addition of 0.1 N KmnO4 and allow the ppt to settle and continue to titrate till the
supernatent liquid shows pink tinge.Take two such piolet readings so that in the 3rd
titration all
permanganate required can be added rapidly and the end point is noted.
Vol.Std KmnO4 consumed x Nor. Of KmnO4
Mn% = x 1.666
Wt in gm of the sample in the aliquot.
Estimation of Mn in Al star:
Dissolve 1gm sample in 3ml of acid mixture(Con.Sil.acid90ml +Conc.Nitric acid 50ml + Conc.
Phopouric acid 95ml + Dis. Water 765ml).Dissolve an accurately weighed sample of std steel
containing a known conc. Of Mn in 30ml of acid miture.Boil,cool and dilute to 100ml with
boiling water.Add 10ml of silver nitate solution and 30ml of 10% ammo.per-sulphate
solution.Heat till permanganic acid colour is obtained.Cool the solution to room temperature add
10ml of NaCl solution to pptAgCl.Titrate quickly the permanganic acid with std. Sod.Arsenite
solution until the pink colour disappears.
Vol. of std. Sodium Arsenite solution consumed
Mn% = x (A x B) / C
Wt. Of the sample taken
Where,
A = % of Mn in std steel sample
B = Wt of saple taken and
C = Vol. of std arsenite solution used for titration.
Settling test:
Fused silica poeder in water with the suspensions CMC&Veegum
Weigh 315gm of fused silic powder,0.315gm of CMC(0.1% of FSP)&1.575gm of
veegum(1% of FSP) in 2 pockects each containing 1.575gm
Dissolve CMC in 53ml distilled water& stir with mechanical stirrer for about 4 minutes
Repeat the same for both the pockets of veegum in a seprate beakers.
61
Take 432ml of distilled water in 1 litre measuring jar and add CMC& stir 4 minutes.
Repeat the same for the two pockets of vegum.
Add 315gm of FSP and stir for 4 minutes.
Keep it for 24 hrs and oserve any sttling take plac e or not.
Specific gravity of FSP:
Take the empty wt of clean,dry pyknometerw1
Fill with water and weigh-w2
Pour out the water and filled with 1/ of FSP&weigh-w2
Fill with water and weigh-w4
(w3-w1)
Specific gravity =
(w3-w1)-(w4-w2)
62
Parts of the wheel:
Cope side:-
Flange
Front rim
Riser pad
Sprue
Front hub face
Hub bore
Front hub fillet
Front plate
Front rim fillet
Drag side:-
Flange
Back rim
Back of flange or
Flange fillet of
Back rim fillet
Back hub face
Hub bore
Back hub fillet
Back plate
Back rim
63
Fracture toughness:
Eventhough the charpy&Impact tests have certain importants they are not considering
for engineering design.LEFM is used for the design problems.Fracture toughness is
one of the material properties like yield strees and used in designs.It is defnied as “the
resistance of the material to resists fracture starting from the preexisting crack /
defect”.
Testing of fracture toughness:
Sample preparation:-
There are so many sample preparation method and one of the method for the
preparation of the sample as per “ASTM,Philadelphiya STP 381133/1965 is as
follows.
Pin hole for apply load
Crack
L(4w) Slot
2C or W / 3
t Crack
w
The length of the specimen is 4 times of the width and the length of slot&crack is 1/3
of the width.Load is applying through the pins in which the sample is inserted.
Procedure:-
Do the preliminary adjustments for the Fracture Toughnes machine and insert the
specimen in to the pins.Apply the load and the material will fracture under plain
strain condition.Note the maximum load(pm ) for the calculation.
Pm w п c
Fracture Toughness (Kic) = x √ tan Mpa a½
w x t (1- ν 2 ) w
Where,
Pm = Maximum load
64
w = width
t = thickness
ν = poison ratio
п = 3.14 and
c = half of the crack length.
The material having higher Kic value will undergo brittle fracture at lesser load and
the material having higher Kic value will undergo ductile fracture.
Time Temp. Deg. C
1 100
2 200
3 300
4 300
5 300
6 300
7 400
8 500
9 600
10 700
11 800
12 900
13 1000
14 1100
15 1200
16 1200
17 1200
18 1200
19 1200
20 1200
65
Time Temp. Deg. C
1 100
2 200
3 300
4 400
5 500
6 600
7 600
8 600
9 600
10 600
11 700
12 800
13 800
14 800
15 800
16 800
17 850
18 900
19 950
20 1000
21 1000
22 1000
23 1000
24 1000
25 1025
26 1050
27 1075
28 1100
29 1125
30 1150
31 1175
32 1200
66
Ladle lining well type with mullite castable.
115
32 50
230
7
Top of molten metal
6
HA 70 230x115x76/70 &
HA 70 230x115x76/65
5 1698
(1650)
1588 4 (1540)
1870
3
2
Steel shell
1 460
HA 70 Mortar
40 Mullite castable
25 110 282
Dia 1655(Dia 1615)
67
Defect analysis of axle.
Billet cutting:
Working pressure:
DA - 0.8 - 1 bar
O2 - 10 bars
The distance between - Approx. equal to OD of the nozzle
Nozzle life - 1200 billets
Nozzle getting blocked due to back-firing,over used,poor quality etc
Conveyors should not move during cutting
Cleen the nozzle at the beginning of each and immediately in case of
back firingReplace the slag bins and never allow bins to overflow
Ensure proper seating of nozzle to torch
Cutting of correct billet length
Select proper billet to be cut as per the specification of R-16&43.
Forging:
LAP:
Improper corner breaking
Indexing problem during forging
Improper conditioning of the bloom surface
Ensure:
Correct corner breaking during forging
Correct 90o during corner breaking and during handover
Defect free surface on bloom and in case surface conditioning is done on
bloom the width of conditioning should be 10 times the depth(8 mm ) of
the conditioning.
Piping:
Insufficient material on forged ends leading to formation of hole in the
journal end face
Uneven distribution of material on both ends of ournal during forging.
Poor gripping marking on jaws / work piece jerking during during
marking
Improper setting / adjustment before cutting in axle cutting machine
Lack of material due to excess scale formation
Ensure
Correct length of billet loaded to RHw
GFM programme for forging is made considering equal distribution of
material for both ends
GFM chuck jaws are welded properly with grip marks to avoid jerking
during forging.
Maintain correct indicator point to point distance as indicated in work
instruction.Maintain 100 to 150 mm of minimum fish end length
69
Ensure no ove saking of billects in RHF.In case of prolonged break
downs put off PHZ and reduced temperature to 1000 deg. C in SZ-I&II
Misfunction during forging:
Catastriphic failure of electrical or mechanical components/failure of
regular power supply leading to in complete forging
Ensure
Ensure machine condition with maint. Staff after PMS or after attending
to breakings.
Idle cycle(without work piece) is checked in auto sequence and check
whether all the blocks in t forging programme is correctly
executed.Ensure that the programme is correct and then recall the work
piece.
The case of failure is to be analyzed and is best when analyzed separately
depending on the case.
In case of power interruption or failure consult MRS for regular supply
of power before starting of forging.Allow 5 minutes for supply to
stabilize.
70
AXLE FLOW CHART Blooms from ASP,Musco&Others. Billet cutting Billet heating in RHF of capacity 80 axles Forging by LFM End cutting Number stamping Cooling through ICB of capacity 30 axles. Normalizing in NF of capacity 80 axles Polimer quenching in quenching tank of capacity 80,000 litres. Cooling through ICB of capacity 42 axles.
Tempering Stock
Sampling for Physical Chemical,Micro,Macro
and Charpy tests at
71
M.Lab. End milling,cup turning and centering at Stn - 1 UT Rough turning at Stns –2 Semi finish of J,D/g&W/s at Stns - 3 Body finish at Stns - 4 Drilling&Tapping at Stns - 5 Finisf of Stns - 3 W/s furnishing at Stns – 7. J&D/g grinding(Centerless Grinding) at Stns - 8 MPT at Stns - 9 W/s of axle Measuring (Automatic) Wheel hub boring(Wheels from Wheel shop stock yard) Wheel set assembly
72
Inspection Painding&Packing
Despatch
Body
W/s fillet
Wheel seat
Journal
CTA
LCB
Body
Axle drawing in Stn-1.
74
Body
W/s
Journal
CTA
Face
LCB
OW/s Flt-N.end
IW/s Flt-N.end
IW/s Flt-F.end
OW/s Flt.F.end
Journal Farend
CTA-Far end
Face Far end
75
Manfacturing of BG Loco axles.
Billet cutting:
Cut the fillet of 300/340 RCS of R-43/1992 bloom in to required length by Saw/Gas
cutting.
Charging in to RHF:
Charge the cut billets in to RHF and soak them at 150 – 1200 deg. C for about 8 hours.
Forging:
Forge the red hot billet at 900 – 1100 deg. C by 6 minutes by GFM long forging
machine.
End cutting:
Remove sufficient discards by gas cut.
Number stamping:
Stamp the serial number of the axle on wheal seat by hot number stamping maching.
Intermediate cooling:
Cool the axle through the intermediate cooling bed till the surface temperature becomes
200 – 250 deg. C.
Heat treatment:
Normalizing:
Charge the axles into NF and soak at 860 – 880 deg. C for about 8 hours.
Hardening;
Quench the normalized hot axles by the polymer quenchant for half an hour.
Tempering:
Charge the quenched axles in to the TF through the intermediate cooling bed and soak
at 610 – 660 for about 11.45 hours.
Air cooling;
Allow the tempered axles in to air cooling for about 36 hours.
Laboratory testing:
Take the lab. sample Each cast wise from the mid radius of wheel seat/journal and
conduct all the required testing .
Machining in AMS:
End milling, centering and LCB:
I f the lab test is ok load the axles in to station-1 in AMS and do the above operations at
station-1 with the surface finishing of 0.8 micron.
Ultrasonic testing:
Do visual examination and carryout the ultrasonic testing and if the axles are passed
stamp the UT punch mark.
Rough turning of axle:
Do the rough of the axle in station-2 as per the dimensions mentioned in the drawing.
Radial scanning of the axle.
Find the longitudinal defects by USL radial scanning machine/manual body scanning.If
the axle pass enter the status in LAN.
77
Final inspection;
Carryout the final inspection thoroughly and if the axle is confirming to all the
requirements made the dispatch arrangements.
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