04/13/2023 1

Grinding• stock removal• dimensional control

Microfinishing • uniform,

Superfinishing • down to sub-1 micron Ra.

04/13/2023 2

• Stock removal • Dimensional accuracy• Uniform surface for further polishing.

Roll Grinding Diagram

04/13/2023 3

Belt Grinder

Materials Commonly Ground with Man-Made Diamond and

CBN

CBN Man-MadeDiamond

Tools SteelsHardened Alloy Steels

Bearing SteelsSuperalloys

Tungsten CarbideTitanium Alloys

GlassCeramicsCermets

CompositesDie SteelCast Iron

KGS Telum CH – Flexible Resin Diamond Tools

Product description: • Hard resin bonded belt• open structured surface • many leading edges allow good cut rate• with coolant & swarf channels. • colour coded for easy identification.• 60 Mesh; 120 Mesh; 200 Mesh; • 400 Mesh; 800 Mesh; 1500 Mesh • 3000 Mesh.

.

KGS Telum CH – Flexible Resin Diamond Tools

A consistent, predictable process. Makes achieving finish specs easy. Delivers required geometry tolerances. An easy-to-use, adaptable solution. Faster dimension & finish attainment. Less operator skills required.

KGS Product Data Sheet

Process Parameters - Surface Finish – Ra Values

Roll grinding with KGS Telum CH Diamond Belts – Tungsten Carbide - HVOF Spray Coating

2.50 2.10 1.60

0.60

0.20

0.10

0.05

0.02

0.01

0.10

1.00

10.00

GY - 50 GN -60

BK - 120 RD - 200 YE - 400 WH -800

BL -1500

OR -3000

Finish Achieved with KGS TELUM CH Belts onHVOF Tungsten Carbide Cylindrical Parts

Ra: µm

SURFACE FINISH RESULTS - per Grit Mesh

Thickness of WC material removed per pass

Colour-Mesh Ra: µm Ra: µin Pulley Micron Thou

GY - 50 2.50 100.00 Fixed 72.0 2.83

GN - 60 2.10 84.00 Fixed 65.0 2.56

BK - 120 1.60 64.00 Fixed 41.0 1.61

RD - 200 0.60 24.00 Fixed 23.0 0.91

YE - 400 0.20 8.00 Floating 3.5 0.14

WH - 800 0.10 4.00 Floating 1.5 0.06

BL - 1500 0.05 2.00 Floating 0.6 0.02

OR - 3000 0.02 0.80 Floating 0.2 0.01

Roll grinding with KGS Telum CH Diamond Belts – Tool Post Grinder Settings - Belt Grinding Machinery

KGS Engineers’ Notes

Process Parameters – Belt Grinding Machinery

KGS Engineers’ Notes

Process Parameters – Floating or Fixed Head

Floating or Fixed Head

Depending on machinery set-up options available for the TPG

FIXED HEAD (Totally Rigid – controlled In-feed)) FLOATING HEAD (Variable Pressure & In-feed) FREE RUNNING (Not grinding on the Pulley)

Each setting affects the grind stock removal and finish.For accurate calibration of 2.5D rolls use Fixed Head.

For slightly conical or curved rolls a Floating Head is generally required.

Floating

Free

PULLEYSHardness and type of Pulley will impact on Ra and stock removal –General purpose serrated rubber rolls with hardness around 60 Shoreare fine for exactly that - general purpose grinding.

For accurate calibration of 2.5D rolls an incompressible non-serrated type is preferable.

This is not so important for the 400 grit down polishing stages.

KGS Engineers’ Notes

Process Parameters – Pulleys

KGS Engineers’ Notes

Process Parameters – Different Materials

Roll grinding with KGS Telum CH Diamond Belts – Surface Finish - HVOF Spray Coating

As a guide – Remember that the previous results are on Tungsten Carbide –Higher stock removal is expected for softer materials such as Chrome Carbide –And a higher Ra and coarser finish for the same parameters.

MICRO-INCHES

TUNGSTEN CARBIDE

CHROME CARBIDE

Colour Grit

Ra: µm Ra: µm

GN - 60 2.42  

BK - 120 1.82  

RD - 200 0.65 1.30

YE - 400 0.16 0.55

WH - 800 0.09 0.38

BL - 1500 0.05 0.13

OR - 3000 0.02 0.07

TUNGSTEN CARBIDE

CHROME CARBIDE

Colour Grit

Ra: µ"Micro-Inch

Ra: µ"Micro-Inch

GN - 60 96.8 -

BK - 120 72.8 -

RD - 200 26.0 52.0

YE - 400 6.4 22.0

WH - 800 3.6 15.2

BL - 1500 2.0 5.2

OR - 3000 0.8 2.8

KGS Engineers’ Notes

Process Parameters – Pressure

Pressure

• The rigidity and pulley hardness limit the grinding pressure available –

• As will the power rating deliverable from the motor.

• Results are EXTREMELY variable by PRESSURE –

• increasing the grinding pressure stock removal can go up by 50% - And Ra can vary by 25% !

Free Running Belt Grinding

KGS Technical Application Overview

INTRODUCTION - Roll Grinding

Surface Conditioning – Yankee Rollers

The large “Yankee Roller” used by the Pulp Industry is often as large as 18 feet diameter by 21 feet long. This roller can get damaged or lose it’s surface condition. The maintenance of the surface for this & other large rolls can be done by a light grind utilizing the “Doctor Blades”.

This is done In Situ by attaching diamond strips along the Doctor Blade by QRS (Velcro) and turning the roll. By positioning the blade at a suitable angle to get a reasonable pressure – this light maintenance can save substantial downtime that would be incurred during a total re-grind.

KGS supplies QRS strips 2”x48” with a 15 degree angle for this operation – usually in Flexis or Telum Pattern and grits 120, 200, 400, 800.

KGS Technical Product Overview

Introduction - GLAZING

GLAZING –

Insufficient pressure/speed or “Firing” can lead to rounding of the sharp cutting edges of the diamond.

Glazing results in a rounded diamond like a glass bead. This CANNOT be re-sharpened like a wheel which can be dressed to expose fresh diamond

Because this KGS Nickel product is a single layer of diamond.

NICKEL

KGS Metallised

Fabric

Belt Backer

KGS Telum CH – CBN version

To avoid the GLAZING issues found with Diamond Belts

Customers can now benefit from using CBN versions.

CBN belts are suitable for either –

Removing existing Hard Coatings and calibrating the metal surface below the coating.

Or –

Removing existing Chrome plated coatings as preparation for replacement HVOF coating.

KGS Business Unit Precision Tools

Existing Patterns

Colour mesh sizeGreen 60 301µm

Black 120 126µm

Red 200 76µm

Yellow 400 40µm

White 800 20µm

Blue 1500 9µm

Orange 3000 4µm

KGS Technical Application Overview

INTRODUCTION - Roll Grinding

Surface Conditioning - Long Strips

Although some rolls require a high reflective finish and low Ra values – other require a specific surface roughness for friction grip &/or ink or water retention.

During the constant use of these rolls, they tend to lose this surface roughness and become “Polished” during use.

Depending on the coating thickness, some rolls can be “Re-furbished” many times before needing stripping and re-coating.

This can be done by diamond belts or long strips on a “Super-Finishing” machine.

KGS now supplies these long strips with circa 3 feet “TAILS” on a BYW3 (Similar to a conventional SiC belt backer) backer on a 3” keyed plastic tube.

KGS Telum CH

Large rolls for Steel Mills Customers often require coarse Ra values as rough as 3.0 or even 4.2 Ra.

This roll, which is slightly tapered normally takes over 8 hours to finish with a diamond wheel.

KGS Telum CH Diamond Belt System took less than one hour, including set-up, to achieve the required finish.

KEY POINT – KGS can massively shorten cycle times compared to diamond wheel grinding.

HVOF WC Coated Roll for Sheet Metal

KGS Telum CH - Retro fitted belt system !

Customers with large diamond wheel grinders can normally benefit from the belt system at a very low capital investment cost, without the investment in a Tool Post Grinder.

Retro-Fit Belt on Diamond Wheel Grinder

Just fit an extra pulley !

By replacing the diamond wheel with an incompressible pulley – and adding an EXTRA smaller pulley - as shown to the back of this picture. With sufficient tension KGS can manufacture to the customer’s required size.

KEY POINT – This set up gave the same Ra values as the KGS R&D team, and took a fraction of the time to both grind and polish both WC & CrC sprayed coatings..

KGS Telum CH – Caterpillar Hydraulic Rams

Caterpillar is supporting a worldwide program to replace the existing Chrome Coating with a suitable new HVOF Coating such as Chrome Carbide.

Caterpillar Hydraulic Rams – Chrome replaced by HVOF CrC

KEY POINT – Picture shows the first grinding pass with KGS Telum CH red 200 grit Belt running on a Dynabrade Tool Post Grinder (48” x 2” Belt).

KGS Telum CH – Dynabrade Belt Finishing Machine

Caterpillar Hydraulic Rams – Free Running Belt Polishing

KEY POINT – Grinding and calibration is done with the coarse belts on an incompressible pulley, as per the previous slide.

Finishing with the finer belts can be supported by the “Free Running” attachment from Dynabrade.

This system gives great flexibility for the operators to both grind and polish much more rapidly than by using a Diamond Wheel followed by an expensive Super-Finishing Machine

KGS Telum CH – Free running dry

KEY POINT –

Telum CH belts are used dry on special hard coatings with a free running set-up.

The advantage from Telum CH to SiC belts is huge.

Not only has the grinding time been decreased from 6 hours to less than 1 hour, there has also been a high cost saving in Silicon Carbide abrasive belts.

- Coating: SiCAlOx 700Hv and TiOx 900Hv- Finish to achieve: Ra: 1 µm Rt: < 15 µm- Cutting speed: 14 m/sec- Traverse rate: 160mm/min- Roll rotation: 400 rpm

Silicon Aluminium Oxide coating – Free Running Belt Grinding

KGS Telum CH – Dynabrade Tool Post Grinder

KEY POINT –

Customer has not been able to achieve a good result with old type belts used.Telum CH belts gave instantly a good result on HVOF coated parts.Both WC and AlTiO coatings were ground and finished within specification.Customer now uses the set-up on a daily base.

Machine: Dynabrade 64991Coatings: WCCo 1200Hv and AlTiOx 700HvFinish to Achieve: Ra 0.15Cutting Speed: 20m/sTraverse Rate: 95mm/minRoll rotation: 500rpmCoolant: Water and 5% oil

Various HVOF coatings – Belt Grinding

04/13/2023 29

04/13/2023 30

Seal Manufacturers Specification for Off Road Machinery Hydraulics

04/13/2023 31

How big is a Micron ?2,000 times size

..0001 Inch.00254 mm

Micron.000039 Inch

.001 mm.001 Inch.0254 mm

.

Human Hair.0035 Inch.0889 mm

Micro-finishing & Belt Grinding

04/13/2023 33

3M film-backed abrasives • Uniform, consistently even finishes • Sub-1 micro inch Ra.

Microfinishing Diagram

04/13/2023 34

Microfinisher

04/13/2023 35

GEM Microfinisher System

04/13/2023 36

04/13/2023 37

Supply

Take Up

New Abrasive

Used Abrasive

Variable Infeed Pressure

Platen

04/13/2023 38

04/13/2023 39

Microfinishing Application

04/13/2023 40

Ra Rq

04/13/2023 41

These three surfaces all have same Ra values

Ra Surface value

04/13/2023 42

04/13/2023 43

04/13/2023 44

Rp: is the maximum height of the Roughness profile above the mean lineWithin the evaluation length (5 cutoffs)

Rpm: is the mean of the 5 Rp values in The successive cutoff lengths

04/13/2023 45

Sk: is the measure of the symmetry of theADF curve about the mean line. Negative Skewness indicates a plateau - dominatedSurface, and a positive skewness indicates

a peak – dominated surface.

ADF Curve

04/13/2023 46

04/13/2023 47

Comparison of Good and Bad Bearing Area

04/13/2023 48

Flex backing

Nickel pellet

Diamonds

Flexible Diamond Construction

04/13/2023 49

Lapping FilmAluminum Oxide & Diamond

3M Imperial Lapping Film-polyester film backing-slurry coated- produce consistent Ra finishes.- available in 0.3 - 60 micron grades.

3M Imperial Diamond Lapping Film- to use on hard material: tungsten carbide, thermal or plasma sprayed ceramic.- micron graded diamond particles- polyester film backing- available in 0.1 - 45 micron grades.

04/13/2023 50

- produce consistent, predictable and repeatable finish- precision micron graded- electrostatically oriented- polyester film backing- resin bonded

3M Microfinishing Film

Properties of Superabrasives and Conventional Abrasives

Thermal Relative

Knoop Compressive Conductivity Abrasion

Material Hardness Strength (psi) Cal/C*cm*s) Resistance

Diamonds 7000-9000 1,260,000 5.0 43

Borazon CBN 4700 945,000 3.3 37

Silicon Carbide 2400 210,000 0.10 14

Aluminum Oxide 2100 500,000 0.08 9

04/13/2023 52

3M Flexible Diamond Belt- flexible backing- durable and longer life- aggressive cutting action- reduce grinding loads- use on rolls harder than 55-60 Rockwell C

3M Imperial Microfinishing Film- produce consistent, predictable and repeatable finish- precision micron graded- electrostatically oriented- polyester film backing- resin bonded

3M Imperial Lapping Film-polyester film backing-slurry coated- produce consistent Ra finishes.- available in 0.3 - 60 micron grades.

3M Imperial Diamond Lapping Film- to use on hard material: tungsten carbide, thermal or plasma sprayed ceramic.- micron graded diamond particles- polyester film backing- available in 0.1 - 45 micron grades.

04/13/2023 53

Superfinisher Application

04/13/2023 54

Microfinisher

04/13/2023 55

Grades 0.3 to 150 MicronAluminum OxideSilicon Carbide

Diamond

04/13/2023 56