Download - Himson Engg Training Report
MAHARANA PRATAP UNIVERSITY OF AGRICULTURE AND
TECHNOLOGY
UDAIPUR (RAJ.)
TRAINING REPORT
ON
CNC Machine
SUBMITTED TO SUBMITTED BY
DR. M.A. SALODA Sir ALOK KUMAR
MECHANICAL ENGG. DEPARTMENT [email protected]
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ACKNOWLEDGEMT
I would like to thank HIMSON ENGINEERING PVT. LTD. SURAT for providing
me an opportunity to work with them. The support and the environment provided to me
during my project was more than what anyone would have expected.
I owe my profound gratitude to Mr. MADHUKAR AJGAONKAR who granted me
the opportunity of working as a summer trainee at mechanical Division.
I would also like to thanks Mr. ASHOK PATEL (G.M.) without his support I
would not be able to perform such a delightful job.
And at last I would like to thanks all the people involve in the training who help
me out in accomplishing it in such a wonderful way.
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INDEX
1. ABOUT THE COMPANY
2. Introduction of CNC Machine
3. Types of tools
4. Tool Material
5. Tool Geometry
6. Tool Holding
7. WORK Holding Device
8. Material Handling
9. Automatic Tool changer
10. Operation of CNC
11. List of G-Codes
12. List of M -Codes
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About the company Himson Engineering Pvt.Ltd. is the flagship company of the Himson
Bhogibhai Group. It is one of the largest manufacturer of textile machinery in India with
the experience of more than 3 decades.
The engineering activities of the group are carried out under the direct control
of Head-Quarters located at Ashwanikumar Road premises at Surat, India.
Initially, in the year 1978, HIMSON tied up with Earnest Scragg Sons Ltd., UK to
manufacture Draw-Texturising Machines in India. Since then, the strategy has been to
acquire the best available technology from the reputed and innovative internationally
leading companies and upgrade the same with help of the experts around the world in
conjuction with our in-house development experts and considerably long machine-
building experience. This strategy has worked very well and eventually, made the
company successful in its field in India & Abroad.
Today, the company enjoys significant market share of Synthetic Yarn
Processing Machinery in India. (Supplied more than 3000 Draw-Texturising machines)
the fast growth has been sustained on continuous upgradation & design and manufacturing
facilities by installing most modern CNC machining centers, fabrication units and metal
finishing shop in-house together with the latest Design and Development Center equipped
with modern CAD/CAM facilities and latest state-of-the art designing software’s to
achieve highest accuracy and maintaining stringent quality standards, benchmarked
against the best in the world. Himson Engineering Pvt Ltd is accredited with ISO
9001:2000 Certification. Today, HIMSON enjoys high reputation for in-house research
and technology developments and an efficient and reliable After-Sales-Services.
In year 1998, HIMSON entered into a technical collaboration with M/s.
Teijin Seiki Textile Machinery Co. Ltd., Japan to manufacture High Speed Draw-
Texturising Machines with Energy Conserving Short Heaters and Auto Doffing.
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Himson Engineering enjoys a very respectful image as supplier of world
class textile machines and is the leader in almost all the products that it manufactures.
Many of the products are exported to developed as well as developing countries. The
manufacturing facilities are now also offered to the Indian & International industries, to
fully exploit the capacities which has been generates over the years.
In the year 2008, Himson Engineering Pvt Ltd also received a prestigious
order from Alok Industries Ltd, one of the leading textile unit in India for supply of Auto
– Doffing Draw Texturising Machine. Himson Engineering Pvt Ltd has executed this
prestigious order for supply of Himson TMT Draw Texturising Machine Model ATH – 12
F/V each with 288 spindles in joint corporation with world re-known TMT Japan (TMT
Machinery , Inc Japan)
This is the 1st time in India Auto Doffing Machines are manufactured and
installed also, this the 1st time in world to supply this machine with 288 spindles.
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INTRODUCTION
Numerical control (NC) refers to the automation of machine tools that are operated by
abstractly programmed commands encoded on a storage medium, as opposed to manually
controlled via hand wheels or levers, or mechanically automated via cams alone. The first NC
machines were built in the 1940s and 1950s, based on existing tools that were modified with
motors that moved the controls to follow points fed into the system on punched tape. These
early servomechanisms were rapidly augmented with analog and digital computers, creating
the modern computer numerical control (CNC) machine tools that have revolutionized the
manufacturing process.
In modern CNC systems, end-to-end component design is highly automated
using computer-aided design (CAD) and computer-aided manufacturing (CAM) programs.
The programs produce a computer file that is interpreted to extract the commands needed to
operate a particular machine via a postprocessor, and then loaded into the CNC machines for
production. Since any particular component might require the use of a number of different
tools-drills, saws, etc., modern machines often combine multiple tools into a single "cell". In
other cases, a number of different machines are used with an external controller and human or
robotic operators that move the component from machine to machine. In either case, the
complex series of steps needed to produce any part is highly automated and produces a part
that closely matches the original CAD design.
Conventional machining, one of the most important material removal methods, is a
collection of material-working processes in which power-driven machine tools, such as
saws, lathes, milling machines, and drill presses, are used with a sharp cutting tool to
mechanically cut the material to achieve the desired geometry. Machining is a part of the
manufacture of almost all metal products, and it is common for other materials, such as wood
and plastic, to be machined. A person who specializes in machining is called a machinist. A
room, building, or company where machining is done is called a machine shop. Much of
modern day machining is controlled by computers using computer numerical control (CNC)
machining. Machining can be a business, a hobby, or both.
The precise meaning of the term "machining" has evolved over the past 1.5 centuries
as technology has advanced. during the machine age, it referred to
as turning, boring, drilling, milling, broaching, sawing, shaping, planning, reaming, and
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tapping, or sometimes to grinding. since the advent of new technologies such as electrical
discharge machining, electrochemical machining, electron beam machining, photochemical
machining and ultrasonic machining, the retronym"conventional machining" can be used to
differentiate the classic technologies from the newer ones. The term "machining" without
qualification usually implies conventional machining
ADVANTAGES OF CNC MACHINE
Higher flexibility
1Increased productivity
Consistent quality
Reduced scrap rate
Reliable operation
Reduced non productive time
Reduced manpower
Shorter cycle time
High accuracy
Reduced lead time
Just in time (JIT) manufacture
Automatic material handling
Lesser floor space
Increased operation safety
Machining on advanced material
CNC Computer Numerical Control (CNC) - A numerical control system in which the data
handling, control sequences, and response to input is determined by an on-board computer system at the machine tool.
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SPECIFICATIONS OF THE CNC MACHINE USED IN COMPANY:
FEELER PVT. LTD.
Model No.-FV600 APC
Serial No.-AP036
APC- Automatic pallet change (Work on the Hydraulic Pressure)
Software used inside of the System : Fanuc Series 0-M
Magazine: It contains 18 tools (maximum) in its pocket at a time.
RPM of spindle:
MAX - 10,000
Generally work on 1200 to 2500.
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Center Drill Size :
BS-3 to BS-14 (used as per required diameter.)
Drill Size Diameter:
MIN:2.5 mm
MAX:30 mm
Generally , ALUMINIUM metal compnents are manufactured by this machine.
Requirements of CNC Toolingi. Higher control on reshaping and inspection should be practiced and repeatable
performances.
ii. Higher control should be exercised on the run out of the multi teeth cutter for better
size control.
iii. Cutting tool should be selected from improves design for improved quality of
workpiece and spade drills, carbide drills, care drills with carbide inserts, reamers,
coated inserts etc.
Construction Features of CNC ToolingThe tools for CNC machines should,
i. Be present and reset outside the machine.
ii. Be quickly changeable to deduce non cutting time.
iii. Have high degree of interchangeability.
iv. Have increased reliability because of high automation and unmanned machining.
Types of CNC Tooling
In order to reduce non productive time to zero level, quickly changeable tool such as
present and qualified must be used. These tool have emerged to reduce the non productive to
the minimum. There are two types of CNC tools
a) Preset tools
b) Qualified tools
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A.)Preset toolsA presetting device is used to present axial and radial position of the tool tip on the tool
holder. Once this is done, the tool holder is ready to be mounted on the machine and produce
a non dimension. Presetting device to various level of sophistication is available. Tool offset,
tool length, and tool diameter compensation facilities available in the present day CNC
machines have brought down the importance by presetting. Accuracy in the order of from -
0.0002 to +0.0002mm can be quickly and easily maintained.
B.)Qualified ToolsThese are tools in which the cutting tip or edge is maintained at a fixed distance within a
tolerance (from-0.05to+0.05) with respect to the reference surface of the folder. In these types
of tools no presetting device is used, therefore investment is less. Rough cuts can be taken
without a trial cut. Control dimensions of the tool are nominal and fixed, hence programming
is easy. Set up time is reduced as elaborate organizing and planning as in preset tool is not
needed. The tool need not be measured individually.
Tool materials
Tooling, surprisingly enough, is often the least understood aspect of CNC equipment.
Given that it is the one element that will most affect the quality of cut and the cutting speed,
operators should spend more time exploring this subject. Cutting tools usually come in three
different materials; high speed steel, carbide and diamond.
High Speed Steel (HSS)HSS is the sharpest of the three materials and the least expensive; however, it wears
the fastest and should only be used on nonabrasive materials. it requires frequent changes and
sharpening and for that reason it is used mostly in cases where the operator will need to cut a
custom profile in-house for a special job.
Solid carbideCarbide tools come in different forms: carbide tipped, carbide inserts and solid
carbide tools. Bear in mind that not all carbide is the same as the crystalline structure varies
greatly between makers of these tools. As a result, these tools react differently to heat,
vibration, and impact and cut loads. Generally, low cost generic carbide tools will wear and
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chip more rapidly than higher priced name brands. Silicon carbide crystals are embedded in a
cobalt binder to form the tool. When the tool is heated, the cobalt binder loses its ability to
hold on to the carbide crystals and it becomes dull. At the same time the hollow space left by
the missing carbide fills up with contaminants from the material being cut, amplifying the
dulling process.
PCBN (Poly Crystalline Cubic Boron Nitrate)
The PCBN tools are used for finishing heat treated alloy steels, tool steels, cast iron,
powered metal, cobalt based alloy, and nickel based super alloys.
PCD (Poly Crystalline Diamond)The PCD tools provides outstanding wear resistance and good surface finish, when
machining highly abrasive non ferrous material such as aluminum, aluminum alloy, cooper
alloys, and carbon and epoxy composites, hard rubber, wood, fiber glass, and plastics.
Summary of application for various cutting tool materialTool material Work material Remark
Carbon steel Low strength, softer material,
non ferrous alloys, plastics
Low cutting speed, low
strength material
Low/medium alloy steel Low strength, softer material,
non ferrous alloys, plastics
Low cutting speed, low
strength material
HSS All material of low and
medium strength and
hardness
Not suitable for low speed
application
Cemented carbide Cast iron, alloy steel,
stainless steel, super alloy
Not for titanium alloys, not
for non ferrous alloys as the
coated grades don’t offer
additional benefits over un
coated.
Ceramics Cast iron, nickel base super
alloys, non ferrous alloys,
plastics
Not for low speed operations
or interrupted cutting. Not for
machining Al, Ti alloys.
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TOOL GEOMETRY
Figure .tool geometry
Tool geometry consists following parameters as -
ShankThe shank is the part of the tool that is held by the tool holder. It is the part of the tool
that has no evidence of machining. The shank must be kept free of contamination, oxidation
and scratching.
Cut diameterThis is the diameter or the width of the cut that the tool will produce.
Length of cutThis is the effective cutting depth of the tool or how deep the tool can cut into the material.
FlutesThis is the part of the tool that augers out the cut material. The number of flutes on a
cutter is important in determining the chip load.
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WORK HOLDING
In order to machine a part on a CNC router the part must be held securely in place.
This seems obvious; however, this is the one area that often causes major headaches. Another
term used for part holding is fixturing. The hold-down system has a significant impact on part
accuracy, quality of finish and on feed speeds and tooling life. Keep in mind that holding the
part securely is important and there is no one system that will properly hold all parts. There
are two fundamentally different types of parts that must be held in place. The first is a flat
part or a sheet of material and the second is a three-dimensional object. The fixturing systems
for each are similar; however, the three-dimensional part normally requires somewhat more
complex arrangements. Some materials require higher cutting forces than others and these
materials will require a more rigid hold-down system. Some materials will vibrate or chatter
when cut.
Fig. Toggle clamp
Types of work holding-
Manual
The most cost effective way to hold down parts to a table is to screw, nail or to bolt
the part to the work table. Other good methods of manually holding parts down are to glue
the part down with regular or thermo fusible glue or with double sided tape. in the case where
a prototype or a single piece will be cut, it might not be cost effective to build a holding
fixture. For short production runs or for fixturing prototypes, another useful method is to use
a toggle clamp. These come in many different configurations and sizes are easy to adjust and
to setup on a jig. One must be careful not to crash the tool or the spindle into the clamp when
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using this kind of device. it is always a good idea to test the program in a dry run at low
speeds before putting such a fixture into production.
VacuumThe most common system for holding down parts on the CNC router is conventional
vacuum. Vacuum is simply the absence of air. the 45 km thick layer of air surrounding the
earth weighs about 14 psi or 29.92" of mercury (hg) or 100 kilopascals (k pa) at sea level.
This column of air pushes down equally on everything in all directions so that no resultant
force is felt on the objects around us. When the air is removed from one side of an object, the
air on the other side now pushes against the object with a force proportional to the absence of
air on the opposite side. This is the basis of vacuum hold-down.the part to be machined is
sealed against the tabletop or a fixture and then the air inside the seal is removed using a
vacuum pump. The air on the outside then pushes the part against the fixture. The vacuum
pressure is not the only thing holding the part against the table. Since lateral pressure is
exerted by the cutter when it is machining the part, the coefficient of friction between the part
and the fixture plays an important part as well. A perfect vacuum is not possible with current
technology, no matter which kind of vacuum pump is used.
Types of Vacuum Work Holding Methods;
a) Conventional vacuum fixturingThis method is mostly used in 5-axis production when trimming molded parts. Since
these parts are almost never flat, special vacuum fixtures are made using plaster to conform to
the part and a rubber seal is used around the vacuum ports.
b) Pod and rail
This vacuum cup type of hold-down is a widespread method of holding parts on a
CNC machine. This is well indicated when one part at a time needs to be machined. There are
many different configurations of pods for different applications and as it takes time to adjust
the pods to different configurations and part sizes, this can be an inefficient way to work. Pod
systems are not the universal solution that some manufacturers advertise.
c) Combination pod/flat tableTable using conventional vacuum is often found. on lower-priced or older systems, a
combination of pods on a flat rotary vane vacuum pumps are relatively inexpensive as they
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are small and are not required to pull a great volume of air. This system works well when
there is a good seal with the part
d) High flow vacuumThis method is often associated with nested based systems. a sacrificial board
otherwise known as a spoil board made particleboard sits atop a vacuum plenum on the
worktable. Flow is so high that a low-pressure area is created on the surface. a flat part that is
laid on this table will be held in place in this low-pressure area without the need for fixtures
or seals.
e) Roller hold-downOther methods of material holding have surfaced in response to specific industry needs.
Roller hold-down systems are often seen in upholstery shops. This method isused to hold
rough and often warped plywood that could not otherwise be held in place by a high flow
vacuum.
Capacity of vacuumThe capacity for vacuum pumps is specified in a couple of different ways, depending
on the type of vacuum pump and the manufacturer. It is important to know the scfm rating of
the pump. It expresses the “actual cubic feet per minute” inlet capacity at a specific vacuum
level. Capacities expressed in cfm or scfm (standard cubic feet per minute) can be very
misleading because one has to take into consideration the volumetric efficiency of the pump
at a specific vacuum level. Rotary vane pumps are generally rated in cfm of free air
displacement, which is the theoretical displacement at 0" hg vacuum. the requirements in
vacuum flow or the capacity of the pump will be different whether vacuum cups, clamps or
high flow universal vacuum tables are being used. A vacuum hold-down where the part rests
on rubber seals may allow thepart to move or wiggle slightly on the soft seals.
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MATERIAL HANDLINGManual material handling is often the norm in furniture and cabinet shops. This
oversight is often at the expense of the manufacturer since the time spent loading and
unloading machines often makes up most of the wasted time in a day. Often, CNC owners
will try to trim seconds off a program or even try to run parts at much faster speeds. This will
result in marginal savings in time and most often result in poor cut quality. Often they
overlook parts and machine idleness and unnecessary material handling in their time analysis.
Most of the efficiencies that can be gained at a CNC work stationary in handling material.
Whether talking about the methods used to handle material or the strategies used to deal with
material handling, large quantities of inventory or work in progress can usually be found all
around the shop. Ensuring that raw material gets to the shipping door as a finished product in
the best possible time will always have the greatest impact on a manufacturer’s bottom line.
Material handling equipment
Scissor lifts
A simple scissor lift at the end of the worktable is often enough when mostly the same
material is being processed all day. When more than one material is used, manufacturers
often pre-stage lifts with the right combination of material so the operator can slide the right
sheet on to the worktable. Care must always be taken when dragging sheet sacross each other
as this can ruin the surface of the sheet below.
Vacuum lifts
Vacuum lifts are a little more expensive than a scissor lift but are also more versatile.
They can pick up sheets from different piles around the CNC and give the added ability of
removing larger parts from the work table once the machining is done .They are usually
mounted on a crane bolted to the floor or wall. Some use high flow vacuum for both the
holding and the lifting, while others use an electric winch for lifting and an air vacuum on a
suction cup for holding.
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Automatic material handling
Automated material handling equipment is mostly found in very largeproduction
plants.Automation can vary from a mechanized conveyorsystem to robotic arms doing most
of the loading and unloading ofthe work.
AUTOMATIC TOOL CHANGER(ATC)
During the operation of a machine tool, considerable amount of time is spent in idle
movement of tool such as tooling engagement and disengagement, tool change in tool setup.
To improve the machine utilization, it is necessary to minimize these idle motions. To that
extent automatic tool changers or ATC as is popular called, plays a very important role.
These are particularly useful in machining operations where a number of tools are to be used
for finishing the job. Though there are still some CNC machine tools which are sold ATC.
For an ATC, it is necessary to have the following statement-
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a) A tool magazine where sufficient number of tools can be stored.
b) The tool adapter that has a provision for pick up by the tool change arm.
c) The ability in the control to perform the tool change function.
d) Tool change procedure.
Tool changing
In the case of turret the tool changing is relatively simple, because of the turret
indexing. However in the case of other tool magazine, it is necessary to have a tool changing
arm which can provide the necessary tool transfer. Generally the tool magazine is placed
closed to the spindle such that the actual tool transfer does consume a lot of time. Typically
tool change time quoted by the various machine tools manufactured range from as low 2 to a
maximum of 10 seconds. The tool change activity requires various motions.
Tool magazine
Tool magazine is to be used have to be considered in terms of following attributes;
Storage capacity
Type and shapes
Tool change procedure
Storage capacity typically starts with about 12 and goes as high as 200 while 30-60 appears to
be most common capacity of the tool magazines. The simplest type of tool magazine is a
turret as shown in figure.
The method combinations tool storage with the tool change procedure, without the
need for a tool change arm. The turret simply indexes to bring the tool in the position of the
machining. Since the spindle is combined with the tool turret as shown in figure. The main
advantages of the system is that the tool is identifies directly with the pocket position and
hence does not require a separate identification. Through it is a relatively simple method, the
time taken for actual tool change is normally more except in the case of a tool in the adjacent
pocket. Further the turret should have the capacity of indexing in both directions to minimize
the change time. The next type of tool magazine is – Drum or disc type magazine. The drum
rotates for the purpose of tool change to bring the required tool to tool change arm and
another type is chain type magazine.
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Operations of CNC
Straight Turning
Drilling
Step Turning
Bearing
Taper Turning
Polishing
Eccentric Turning
Tapping
Chamfering
Parting 0ff
Thread Cutting
Reaming
Facing
Counter Boaring
Spinning
Under Cutting
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List of G-codes commonly found on Feeler CNC Machine:
Code Description
G00 Rapid positioning
G01 Linear interpolation
G02 Circular interpolation, clockwise
G03 Circular interpolation, counterclockwise
G04 Dwell
G05P10000 High-precision contour control (HPCC)
G05.1 Q1. Ai Nano contour control
G06.1 Non Uniform Rational B Spline Machining
G07 Imaginary axis designation
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G09 Exact stop check
G10 Programmable data input
G11 Data write cancel
G12 Full-circle interpolation, clockwise
G13 Full-circle interpolation, counterclockwise
G17 XY plane selection
G18 ZX plane selection
G19 YZ plane selection
G20 Programming ininches
G21 Programming inmillimeters (mm)
G28 Return to home position (machine zero, aka machine reference point)
G30 Return to secondary home position (machine zero, aka machine reference point)
G31 Skip function (used for probes and tool length measurement systems)
G32 Single-point threading, longhand style (if not using a
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cycle, e.g., G76)
G33 Constant-pitchthreading
G33 Single-point threading, longhand style (if not using a cycle, e.g., G76)
G34 Variable-pitch threading
G40 Tool radius compensation off
G41 Tool radius compensation left
G42 Tool radius compensation right
G43 Tool height offset compensation negative
G44 Tool height offset compensation positive
G45 Axis offset single increase
G46 Axis offset single decrease
G47 Axis offset double increase
G48 Axis offset double decrease
G49 Tool length offset compensation cancel
G50 Define the maximum spindle speed
G50 Scaling function cancel
G50Position register (programming of vector from part zero to tool tip)
G52 Local coordinate system (LCS)
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G53 Machine coordinate system
G54 to G59 Work coordinate systems (WCSs)
G54.1 P1 to P48 Extended work coordinate systems
G70 Fixed cycle, multiple repetitive cycle, for finishing (including contours)
G71 Fixed cycle, multiple repetitive cycle, for roughing (Z-axis emphasis)
G72 Fixed cycle, multiple repetitive cycle, for roughing (X-axis emphasis)
G73 Fixed cycle, multiple repetitive cycle, for roughing, with pattern repetition
G73 Peck drilling cycle for milling - high-speed (NO full retraction from pecks)
G74 Peck drilling cycle for turning
G74Tapping cycle for milling, lefthand thread, M04 spindle direction
G75 Peck grooving cycle for turning
G76 Fine boring cycle for milling
G76 Threading cycle for turning, multiple repetitive cycle
G80 Cancel canned cycle
G81 Simple drilling cycle
G82 Drilling cycle with dwell
G83 Peck drilling cycle (full retraction from pecks)
G84 Tapping cycle,righthand thread,M03 spindle direction
G84.2 Tapping cycle, righthand thread,M03 spindle direction,
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rigid toolholder
G90 Absolute programming
G90 Fixed cycle, simple cycle, for roughing (Z-axis emphasis)
G91 Incremental programming
G92 Position register (programming of vector from part zero to tool tip)
G92 Threading cycle, simple cycle
G94 Feedrate per minute
G94 Fixed cycle, simple cycle, for roughing (X-axis emphasis)
G95 Feedrate per revolution
G96 Constant surface speed (CSS)
G97 Constant spindle speed
G98 Return to initial Z level in canned cycle
G98 Feedrate per minute (group type A)
G99 Return to R level in canned cycle
G99 Feedrate per revolution (group type A)
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List of M-codes commonly found on Filler CNC Machine :
Code Description
M00 Compulsory stop
M01 Optional stop
M02 End of program
M03 Spindle on (clockwise rotation)
M04 Spindle on (counterclockwise rotation)
M05 Spindle stop
M06 Automatic tool change (ATC)
M07 Coolant on (mist)
M08 Coolant on (flood)
M09 Coolant off
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M10 Pallet clamp on
M11 Pallet clamp off
M13 Spindle on (clockwise rotation) and coolant on (flood)
M19 Spindle orientation
M21 Mirror, X-axis
M21 Tailstock forward
M22 Mirror, Y-axis
M22 Tailstock backward
M23 Mirror OFF
M23 Thread gradual pullout ON
M24 Thread gradual pullout OFF
M30 End of program with return to program top
M41 Gear select - gear 1
M42 Gear select - gear 2
M43 Gear select - gear 3
M44 Gear select - gear 4
M48 Feedrate override allowed
M49 Feedrate override NOT allowed
M52 Unload Last tool from spindle
M60 Automatic pallet change (APC)
M98 Subprogram call
M99 Subprogram end
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BIBLIOGRAPHY
www.wikinpedia.org www.google.co.in (for images) www.himpson.in CTAE library
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