High PerformanceGrinding Solutions

SAK ABRASIVES LIMITED

TOPLINE

SAK ABRASIVES LIMITED

Sak Abrasives Limited started in 1997 with the objective of supplying Indian Industries with

high-performance grinding wheels at affordable prices. At that time the growing Indian market

was supplied by very few companies and the trend towards precision-engineered products

left a void that we were quick to fill. In collaboration with the Swiss company,

Rastawerk – Switzerland A.G, we started our range with basic resin bonded DC and

cut off wheels made out of a plant in Chennai, India.

Since then there has been no looking back as we expanded our product line in response to

the evolving need of our customers. Backed by a philosophy of rapid but sustainable change

we developed a full range of resin and vitrified bonded abrasives, coated abrasives and the

latest addition of Super Abrasives. This has been accompanied by continual investment in the

up-gradation and modernization of our plant, paving the road to the future.

Irrespective of whether you are regrinding or making new tools, we have the diamond or

CBN grinding wheel for you. With the help of our technical partner, Superabrasives INC, USA,

we have worked with a number of OEM's and we understand the machinery demands and the

requirement of grinding wheels. Products like Carbide, Stainless or High-speed steel end mills,

drills, punches, reamers and hole saws require multiple steps in manufacturing and we have

developed bond systems and have qualified exact specifications for each operation. With the

latest technology, we are offering all types of Diamond / CBN wheels that comply with

FEPA standards and that are used on CNC machines such as Walters, Rollomatic, ANCA,

Royces, Wendt, TGT, WIDMA etc. in the following industries / applications:

- Rotary Tools

- Cutting Tool Industries

- Wood Working Tools

- Tool Resharpening / Restoring

- Optical Profile Grinding

L e t t h e s p a r k s f l y . . .

Usage of Diamond and CBN wheelsIn general, Diamond is used to grind Non- ferrous material as it reacts with iron. On the other hand, CBN is used to grind Ferrous material.

DIAMOND (D) CBN (CB)

Solid CarbideOxide CeramicsGlassStoneProcelain, Stone WareSemi-conductorsFerriteStellite- hard facingCast Iron

High Speed SteelTool SteelHeat Treated SteelChromium SteelCase Hardened SteelSuper AlloysBearing SteelStainless SteelInconel

APPLICATIONS WHEEL SHAPE

Fluting

Primary and secondary relief or end work

Gashing

Grinding top/bottom inserts

Grinding peripheral inserts

OD grinding

Centerless grinding

Surface grinding

1A1,1V1,1F1

11V9

1V1, 12V9 – 30° or 45°

6A2

2A2T

1A1, 1A1J

1A1, 1A1J

1A1

GRIT SIZE

USA FEPA

20/30

30/40

35/40

40/50

50/60

60/80

80/100

100/120

120/140

140/170

170/200

200/230

230/270

270/325

325/400

D852

D602

D501

D427

D301

D252

D181

D151

D126

D107

D91

D76

D64

D54

D46

COARSER

FINER

Shape Of Wheels

SAK Wheel Nomenclature

D64 B4 602SW

D: Abrasive Type S: Sak Abrasives64: Grit Size

B: Resinoid602: Bond Type

2: Concentration

D: Diamond

CB: CBN

(FEPA Standard

D64-230/270,

D76-200/230 etc)

64: Finishing

126: Roughing

(25-1 ,50-2 , 75-3,

100-4………. Etc)

601: Carbide, coolant with Oil, Face

602: Carbide, coolant with Oil & Water, Profiles

603: Steel, coolant with Oil & Water, profile & slicing

604: Steel, coolant with Oil & Water, ID, Face & Dry Grinding.

605: Carbide & Steel, coolant with Oil & Water, OD, ID,

Plunge, Surface, Centre less for Grit 325 and above

606: Carbide, coolant with water, OD, Plunge, Surface, Centre Less

W: Wet Grinding

D: Dry Grinding

Sak Abrasives Limited

14A11A1

X

HD

T

14F1D

HJ

X

U2R

=U

T

3A1

D

HJ

T

X

U

6A2

H

XE

D

W

T

D

HJ

TU

X

1V1

HD

X

OV

T

9A3

D

H W

T

XE

1F1

HD

T

X

12V9

DKX

045

HJ

EU

T

11V9

DK X

U

E

HJ

070T

6A9

K

X

HD

UE

T

2A2T

DW

X

H

B.CTH’D.

T

ANSI Wheel Shape Identification System

11 B 91 Choose basic core shape

2 Choose shape of abrasive cross section

3 Select location of abrasive section

1. Choose basic core shape

2. Abrasive Cross Sections And Marks

3. Location of abrasive section & marks

1

9

2

11

3

12 14

4 6

15

A AH B C CH D DD E EE

F FF G H J K L LL

M P Q QQ S

V YU

1. Periphery

2. Side

3. Both Sides

4. Inside Bevel

or Arc

5. Outside Bevel

or Arc8. Throughout

7. Part of side

9. Corner

10. Annular

Note: Solid black area indicates abrasive placement.

6. Part of periphery

Sak Abrasives Limited

PRODUCT IDENTIFICATION

TECHNICAL INFORMATION

Technical Guidelines

Spec Check

Avoid Excessive Feeds

Excessive feeds will result inpremature wheel wear.Excessive feed rates arecharacterized by:

- A hard grinding sound- Chatter- Burn- High wheel wear rate- Vibration

Avoid Grinding Steel

Avoid steel when grinding withdiamond wheels. Keep theamount of steel ground to anabsolute minimum.

On brazed tools, use aluminumoxide wheel to back off the steelshank.

A high lubricity grinding fluidshould be used.

Use Rigid Work Support

All workpieces should besupported firmly during thegrinding process. Any amount ofvibration will cause wheel wearand produce chatter or wavemarks on the ground surface.

On work ground betweencenters, centerholds should beproperly prepared.

Minimize work overhang.

If the ground work is supportedby a work finger, ensure thefinger is strong enough toprovide vibration-free support.

Coolant – Grind Wet

Diamond wheels should beused with a full flood coolantproperly directed towards thegrinding zone. Water with a rustinhibitor is recommended.

When flood application can’t beused, try mist or spray application.

Use compressed air to“atomize” water or soluble oil.

Direct the spray at thegrinding zone to helpdissipate heat and preventheat damage to the work.

TROUBLESHOOTING GUIDE – DRY GRINDING

PROBLEM POSSIBLE CAUSES SUGGESTED CORRECTION

Burning (excessive heat)

Chatter

Poor finish

Wheel loaded or glazedExcessive feed rateWheel too durable

Wheel out of truth

Grit size too coarseExcessive feed rate

Dress wheel with a dressing stickReduce infeed of wheel or workpieceUse freer cutting specification or slow down wheel speed

True wheel; ensure it is not slipping on mount

Select a finer grit sizeReduce infeed of wheel or workpiece

SUGGESTED CORRECTION

Re-dress wheelApply coolant directly to wheel/workpiece interfaceReduce downfeed and/or crossfeed

Apply coolant to flood wheel/work surfaceIncrease wheel speed (observe maximum operating speed)Use lighter dressing pressureChange grit or grade; use higher concentration

Dress lightly until wheel opens upDress lightly until wheel opens upIncrease coolant flow to keep wheel surface cleanNever run wheel with coolant turned off

True wheel; ensure it is not slipping on mount

Increase feed rate; increase wheel speed (Do not exceed wheel MOS)

Use lighter dressing pressureStop dressing as soon as wheel starts to consume stick rapidlySelect a finer grit sizeApply heavy flood so it reaches wheel/work interface

TROUBLESHOOTING GUIDE – WET GRINDING

PROBLEM POSSIBLE CAUSES

Burning (excessive heat)

Short wheel life

Wheel will not cut

Chatter

Slow cutting

Poor finish

Wheel glazed or loadedPoor coolant placementExcessive material removal rate

Incorrect coolant flowLow wheel speedExcessive dressingWheel too soft or too hard

Glazed by truingWheel loaded

Wheel out of truth

Low feeds and speeds

Excessive dressing

Grit size too coarsePoor coolant flow or location

7000

6000

5000

4000

3000

2000

1000

0

MATERIAL HARDNESS SCALESuperabrasives is a term used to describe thoseabrasives of extreme hardness, which produceoutstanding results when properly used onspecific applications. The following chart provides a hardness comparison (Knoop Hardness Scale) between diamond and CBN superabrasives, aluminum oxide and silicon carbide standard abrasives, and some common materials these abrasives are used to grind.

Diamond

Polycrysta

lline Diamond

CBN Abrasive

Polycrysta

lline Boron Nitride

Vanadium Carbide

Silicon Carbide Abrasive

Silicon Carbide

Aluminum Oxide Abrasive

Tungsten Carbide

Hard Steel H

rc Glass

Soft Steel H

rb 85

Kno

op H

ardne

ss (

H.K

.)

RECOMMENDATIONS & GUIDELINES FOR THE SELECTION OF CONCENTRATION IN RELATION TO GRINDING FORCES

Three factors affect the choice of Abrasive grit:

GRINDINGFACTORS

AREA OF CONTACT BETWEENWHEEL & WORKPIECE

PROFILE &EDGE STRENGTH

CUTTING EFFICIENCYSOFT GRINDINGBOND

Concentration Low High

Large Small

High High

Hard

Low Low

Soft

Quantity of material to be removedSurface-finish and wheel lifeMaterial removal and wheel life

Surface Finish

Permissible Cutting Depth

Surface Finish Vs Grit Size

Surface Finish depends on the adjustment for oscillation-grinding (on pass and in-feed depth) and for plunge-grinding. A wheel used properly shows a grit penetration depth equal to 1/5-1/8 of the grit dimension. If the level of roughness needed is known, it is possible to choose the right grit using the following charts:

For Oscillation Grinding

Selection Guideline for Grinding of Carbide & Ceramics

D

46

D

213

D

181

D

151

D

126

D

107

D

91

D

76

D

64

D

54

FEPA grit size

Cu

ttin

g D

epth

0.04

0.035

0.03

0.025

0.02

0.015

0.01

0.005

mm

181

107

76

54

157

AA[µ”]Ra[µ”]

Swiss

20,05

N2

30,1

N3

80,2

N4

160,4

N5

320,8

N6

641,6

N7

1253,2

N8

(cutting speed approx.: 25m/sec - table speed 15m/min - coolant emulsion)

The Concentration specifies the carats of the abrasive grain (Diamond or CBN) processed in

3the 1cm abrasive layer.The Concentration influences the performance of the Diamond and CBN Grinding tools decisively. It effects:

The service life of the grinding toolThe stock removal rateProfile retentionThe dimensional constant of the machined work piece.The finish smoothness of the machined work piece.The price of the grinding tool

Concentration

Sak Abrasives Limited

Expected Surface Finish by Grit SizeUse these charts as guides only. Surface finish is affected by several variables: machinetype and condition, type of material ground, coolant, wheel speed, bond system, etc.

DIAMOND

CBN

GRIT SIZEEXPECTED FINISH

WITH OSCILLATIONEXPECTED FINISH

MICRON Ra

GRIT SIZE

100120150180220320400

100120150180220320400

EXPECTED FINISHMICRO INCH AA

24 - 3216 - 1814 - 1612 - 1410 - 1287 - 8

35 - 4030 - 3525 - 3020 - 2515 - 2010 - 154 - 8

0.875 - 1.0000.750 - 0.8750.625 - 0.7500.500 - 0.6250.375 - 0.5000.250 - 0.3750.100 - 0.200

EXPECTED FINISHMICRON Ra

0.60 - 0.800.40 - 0.450.35 - 0.400.30 - 0.350.25 - 0.350.20 - 0.250.18 - 0.20

DRY GRINDING

WHEEL SPEED CALCULATION:

CUP WHEELS

CUP WHEELS

PERIPHERAL WHEELS

PERIPHERAL WHEELS

Diamond Grinding Wheels

Diamond Grinding Wheels

To convert m/s to SFPM

To convert SFPM to M/S

To convert RPM to SFPM

Resin Bond Wheels

Resin Bond Wheels

11V9, 12V9, 15V9, etc.

11V9, 12V9, 15V9, etc.

Multiply M/S x 196.85 = SFPM

Divide SFPM by 196.85 = M/S

Multiply wheel diameter in inches x RPM x 0.262

4921 to 7874 SFPM25 to 40 m/s

2756 to 3543 SFPM14 to 18 m/s

1A1, 1V1, 1A1R, etc.

4921 to 7874 SFPM25 to 40 m/s

CBN GRINDING WHEELS

Resin Bond Wheels 5906 to 9843 SFPM30 to 50 m/s

5906 to 9843 SFPM30 to 50 m/s

1A1, 1V1, 1A1R, etc.

2756 to 3543 SFPM14 to 18 m/s

CBN GRINDING WHEELS

Resin Bond Wheels 2953 to 5906 SFPM15 to 30 m/s

2953 to 5906 SFPM15 to 30 m/s

M/S = Meters/second RPM = Revolutions Per Minute SFPM = Surface Feet Per Minute

Recommended Wheel Speeds for Diamond and CBN WheelsWET GRINDING

EXPECTED FINISHPLUNGE

40 - 4535 - 4030 - 3525 - 3020 - 2515 - 205 - 10

MAXIMUM DEPTH OF CUTPER PASS FOR GRIT SIZE

0.001” - 0.002”0.001” - 0.002”0.001” - 0.002”0.0007” - 0.001”0.0007” - 0.001”0.0004” - 0.0006”0.0003” - 0.0005”

INCH

0.025 - 0.0510.025 - 0.0510.025 - 0.0510.018 - 0.0250.018 - 0.0250.010 - 0.0150.008 - 0.013

MM

Sak Abrasives Limited

Marketing Office

SP Infocity, 40, MGR Salai,Perungudi, Kandanchavadi,Chennai - 600 096

Phone: 91-44-2454 3500Fax: 91-44-2454 3510

Web: www.sakabrasives.com

Factory

Phone: 91-44-2792 3104Fax: 91-44-2792 3009

B-49/W, Sipcot Industrial Complex,Gummidipoondi - 601 201

Email US

INTERNATIONALexports@sakabrasives.com

INDIAsuper@sakabrasives.com

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