Report Quality

7/31/2019 Report Quality

1/26

A

REPORT

ON

QUALITY PARAMETERS AND METHDS AT SKF INDIA

1) Gaurav Mittal

2)

PREPARED IN PARTIAL FULFILMENT

OF QULITY CONTROL

AT

BITS PILANI


2/26

Acknowledgements


3/26

Table of Contents:

Acknowledgements

1. Introduction

1.1 SKF

1.1.1 SKF Quality Program

1.1.2 SKF Six Sigma

1.2 Bearing Basics

1.2.1 Tapered Roller Bearing

1.3 Shop Floor

1.3.1 The T8 Channel

2. Quality Measurement and Machines

2.1 Waviness and Roundness Analyser

2.2 Ring Dimension Measuring Machine

2.3 Ultrasonic Tester

2.4 Vibration tester (MVR)

2.5 Capability Test

3. Problem Statement and Losses

4. Methodology Followed (Rejection analysis)

4.1 Analysis


4/26

4.2 Dominant Causes and Suggestions

5. Appendix

6. Conclusion

7. References


5/26

1. Introduction

The purpose of this project is to apply our knowledge in an organization. Through this, we

will have better understanding of quality control methods..

SKF, Svenska Kullagerfabriken AB, later AB SKF, is a Swedish bearing company founded

in 1907 bySven Wingqvist as a multi-row self-aligning radial ball bearing production

company. By 1910, the company had 325 employees and a subsidiary in theUnited

Kingdom. By 1912, SKF was represented in 32 countries and by 1930, a staff of over

21,000 were employed in 12 manufacturingfacilities worldwide with the largest in

Philadelphia. In the 1970s SKF embarked on a massive production rationalization program

in Europe. Today SKF is the largest bearing manufacturer in the world and employs

approximately 40,000 people in approximately 100 manufacturing sites that span 70

countries. The SKF Group currently consists of approximately one hundred and fifty

companies all over the world. Presently supplying bearings, seals, lubrication and

lubrication systems, maintenance products, mechatronics products, power transmission

product and related services globally.

SKF India delivers high end technical knowledge starting with self-aligning ball bearing,

spherical roller bearing, the hub bearing units that are widely used in cars & truck wheelends in addition to the new and latest revolutionary CARB bearings that find specialized

application in steel plants & paper mills. In fact the company domestically manufactures

around 60 sizes of deep groove ball bearings, 70 sizes of taper roller bearings, textile

machinery component in addition to catering the needs of automobile, electrical & industrial

OEM and aftermarket customers.

SKF QUALITY PROGRAM
http://en.wikipedia.org/wiki/Swedenhttp://en.wikipedia.org/wiki/Rolling-element_bearinghttp://en.wikipedia.org/wiki/Companyhttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/Manufacturinghttp://en.wikipedia.org/wiki/Manufacturinghttp://en.wikipedia.org/wiki/Manufacturinghttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/United_Kingdomhttp://en.wikipedia.org/wiki/Companyhttp://en.wikipedia.org/wiki/Rolling-element_bearinghttp://en.wikipedia.org/wiki/Sweden


6/26

1.1 SKF SIX SIGMA

SKF employs a Six Sigma business approach. CEO Tom Johnstone was recognized as the

Premier Six Sigma Leader of the year (2006) in Europe. Six Sigma (also written as 6

Sigma, 6) is a systematic, measurement-based methodology that focuses on process

improvement and variation reduction through the identification and removal of the causes of

defects and errors. By eliminating variability and defects which undermine product and

service quality, Six Sigma can bring about vast improvements in performance, profits,

employee morale, quality of products and services and customer confidence. At the heart of

the Six Sigma methodology is the DMAIC (Define, Measure, Analyse, Improve, Control)

model.

1.1.1 Benefits of Six Sigma

Reduces variability

Improves quality reduces defects and errors

Improves reliability of products and processes

Reduces cost of operations

Improves capacity and output

Improve productivity

Improves customer satisfaction

Improves profits


7/26

Bearing Basics

Bearings are designed to overcome friction to provide ease of rotation . Bearings are

designed to support shafts and allow free rotation on applied loads. There are three basic

types of load

Radialloads are applied perpendicular to the shaft (the bearings axis of rotation )

Axial(thrust) loads are applied parallel to the axis of rotation.

Combination load is encountered when the bearing simultaneously experiences a radial

and axial load

Bearing types-

1)-Plain 4)-Self aligning ball 7)-Needle

2)-Deep groove 5)-Cylindrical roller 8)-Spherical

3)-Angular contact 6)-Tapered roller 9)-Toroidal

Tapered Roller-

Tapered roller bearings are bearings that can take large axial forces (i.e., they are

good thrust bearings) as well as being able to sustain large radial forces. The inner and

outer ring raceways are segments of cones and the rollers are also made with a taper so

that the conical surfaces of the raceways and the roller axes if projected, would all meet at

a common point on the main axis of the bearing.

The basic components of a tapered roller bearing are:

Cage

Roller

Inner Ring

Outer Ring


8/26

Figure 1: BT1-0222A type of TRB

The figure shows the CAD model of a bearing BT1-0222A made in Pro E Wildfire 4.0. The

outer ring is partially cut so as to show the arrangement of rollers in the assembled cone.


9/26

1.3 Shop Floor

The shop floor has a large number of channels each devoted to different processes and

machining different kinds of bearings like T1,T2,T8 make tapered roller bearings and the

DGBB make deep grooved ball bearings. Our report is based on reducing the rejection of

the MVR machine which is situated near the end of the T8 channel. A brief description of

the T8 channel is given below.

1.3.1 The T8 channel

The T8 channel manufactures tapered roller bearings. It is subdivided into two channels for

the inner and the outer ring respectively. After heat treatment the IR & OR come to the T8

channel. Here they undergo the following processes sequentially:-

1.3.1.1 Inner ring channel

1 hardness checking

2 face grinding

3 width checking

4 land track grinding

5

bore grinding

6 flange grinding

7 track honing

8 marking

9 assembly.

10

cone height checking

11 oiling

12 MVR

13 missing roller checking

13 visual inspection


10/26

1.3.1.2 Outer ring channel

The channel is dedicated to meet the demands of many companies like Volkswagen,

John Deere, Ford, Volvo, Maruti-Suzuki.

1 face grinding

2 OD grinding

3 track grinding

4 track honing

5 marking

6 oiling

7 cup height checking

8 visual inspection


11/26

2. Quality Measurement and Machines-

As a major engineering company, SKF relies on making sure that the products and services

it provides live up to its own high expectations. Measurement and quality-assurance

systems provide the SKF Group with the means to do just that. The SKF Group has its own

dedicated Quality Technology Centre (QTC) that is now offering its expertise to other

companies worldwide

2.1 Quality Measuring Machines

A range of technologies and measurement approaches are available:

Waviness, roundness and form analysis

Low noise and vibration of bearings is becoming more and more important in mostapplications. One of the main reasons for high vibration levels is waviness on the bearingcomponents

Noise and vibration testing for bearings

low noise and vibration is becoming more and more important in most applications. Besideothers, a noisy application might be caused by wavy bearing components, by localdefects in the rings and balls, or by dirt particles in the bearing. All of these bearing qualityissues can be tested with QTCs bearing vibration equipment

Dimension testing

Stricter process requirements due to tighter tolerances and higher output results inhigher demands on the measuring machine capability and time pressure when resetting

measuring equipment.

Optical inspection

in optical systems the following basic physical principle is involved:

"The appearance of the product is different to what we have decided to be acceptable."

That appearance is dependent on three factors:

The condition of the object - colour, roughness, etc. The nature of the illumination - White light, coloured light, laser light etc.


12/26

The properties of the sensors - Matrix Camera, Line Camera, Single Photo-detectoretc.

QTC is specialised in all three of these areas, as well as in signal processing and handlingof the products

Non-destructive testing

Is the inspection of components in a way that ensures that the components are defect freeor comply with certain quality requirements in such a way as to retain their usability. Thismeans that where necessary, 100% of production can be inspected in real time, removingoutliers from your production without adding to your production cycle time.

2.2. Capability test

After every finishing process for the accuracy up to micron level it is necessary to do

capability test.

The methodology follows is

1) Data collection

2) Analysis

3) Suggestions to improve performance

Data collection - can be done in to different ways:-

1) Short term data collection- We collect continuous data of 100-150 bearing.

2) Long term data collection- We collect samples of 5-10 bearings from different shifts at

Different times.

Analysis- Collected data is loaded into statistical software like MINITAB. Then upper

specified and lower specified limits are entered. After that mean and rang control chart are

prepared. Then the points which Lie outside the USL and LSL analysed by using remarks

which we have noted in data collection sheet. So the points which corresponds to the

special causes are eliminated and responsible main causes can be find out.


13/26

Short term data :

Time Min Max Ovality Avg Min Max

-4 -1 -6 -2-6 -3 -7 -4

-5 -2 -5 -3

1 4 -1 1

-3 0 -4 0

-2 0 -3 -1

-2 0 -5 -1

Bore grinding m/c no : 1806 Inner Ring :BT1022A

Top Bottom

Mean and Rang chart for top

Mean and rang chart for bottom

343128252219161310741

2

0

-2

-4

-6

Sample

SampleMean

__X=-2.09

UC L=2.55

LCL=-6.72

343128252219161310741

8

6

4

2

0

Sample

SampleRange

_R=2.467

UC L=8.059

LCL=0

Xbar-R Chart of C1, ..., C2

343128252219161310741

0

-2

-4

-6

-8

Sample

Sample

Mean

__

X=-3.46

UC L=1.28

LCL=-8.19

343128252219161310741

8

6

4

2

0

Sample

SampleRange

_R=2.518

UC L=8.229

LCL=0



14/26

Long term data:

Time Min Max Ovality Avg Min Max

10:00 -9 -7 -8 -5

-11 -9 -13 -10

-10 -7 -9 -7

-4.5 -2 -7 -3.5

-9 -7 -8.5 -7

10:10 -7 -3 -5 -3

-8 -5 -8 -5

Bore grinding m/c no : 845 Inner Ring :6308

Top Bottom

Mean and rang chart for top

343128252219161310741

0.0

-2.5

-5.0

-7.5

-10.0

Sample

SampleMean

__X=-6.53

UC L=-2.60

LCL=-10.46

343128252219161310741

6.0

4.5

3.0

1.5

0.0

Sample

SampleRange

_R=2.090

UC L=6.830

LCL=0

1

1

11

11


343128252219161310741

0.0

-2.5

-5.0

-7.5

-10.0

Sample

SampleMean

__X=-6.65

UC L=-2.36

LCL=-10.94

343128252219161310741

8

6

4

2

0

Sample

Sam

pleRange

_R=2.281

UC L=7.454

LCL=0

111

11



15/26

MVR (Vibration Tester):

The MVR is a vibration testing machine for bearings. It has an OR which fixes itself onto the

cone and accepts or rejects it by vibrational analysis on the basis of Fourier analysis in theform of 62 bands relating the IR, the tapered roller as well as the bearing as a whole. The

bands check for waviness and hit marks on the track and flange of the IR which constitute

its functional areas.

By doing Fourier analysis of the incoming bearing data, the MVR can detect from which

component noise (vibration) is coming and what kind of noise it is. The following

parameters are used in the MVR:-

1) Crest: for Inner Ring (IR)

for TR (Tapered Roller)

for Mix (complete signal)

Crest is a hint for hit marks on IR or roller.However, If Crest Mix is indicated, it is a hint for

dirt or for a defect in the OR.

2) Peak: it is analogous to Crest. It implies hit marks or dirt.

3) RMS: IR: IR part of RMS signal

TR: roller part of RMS signal

Mix: complete signal

RMS is the root mean square signal which detects honing error and Mix RMS is a hint for

defect in the OR.

4)Bands: the Fourier analysis does also detect waviness of the components.

The signal is split up into 10 bands (0...9) each into IR-signals(SK1) and Roller-

signals(SK2)

False rejections

While using the MVR, however, we have to be very careful while dealing with rejections

because there is also the possibility that the MVR would falsely reject bearings. This could

happen due to the following reasons:-

1) Belt from the motor to the spindle is defective.

2) The mandrel diameter too small (IR is sliding on the mandrel).


16/26

3) Mandrel height is incorrect. This may cause the IR to slide on the plate and create noise.

4) Presence of dirt or hit mark in the mandrel holder in the spindle

5) Spindle misalignment.

6) Heating up of the bearing resulting in its expansion and hence causing 2)

In spite of all this, it is worth knowing that the MVR does not give false acceptance. If a

bearing has a fault it is sure to be rejected by the MVR


17/26

3. Origin of the Problem Statement:

Recent observations showed that the T8 Taper Roller Bearing manufacturing channel was

not performing efficiently and the amount of rejection on the MVR vibration testing machine

was very high in addition to the process losses at various stages along the channel. It has

been observed that the daily efficiency of the channel is around 60% which is quite low and

the daily rejection on an average is around 10% which is also quite significant. Therefore

our project aims at reducing the rejection on this channel

Losses incurred due to rejection:

SKF follows 100% inspection methodology. T8 Taper Roller Bearing manufacturing

channel has very high rejection around 12%. The accepted bearings are sent to the large scale manufacturers,

The rejected bearing are tested on noise and vibration analyzer and are sold in the

retail markets with a loss of 30% in price.


18/26

4. Methodology followed:

The Six Sigma methodology for problem solving includes the following stages:

Define

Measure Analyse

Improve

Control

Following the Six Sigma methodology we will be first collecting the data at various stages

along the channel focusing primarily on collecting the data for MVR rejection for different

shifts. The data collection will be followed by the analysis of the data using different

statistical tools and methods of analysis. The analysis aims to identify the major causes of

rejection. Based on the results of the analysis we will try to suggest suitable measures so

as to reduce the rejection.

MVR Rejection Parameters:

Waviness IR(Inner Ring)

Waviness TR(Taper Roller)

Waviness Bearing

Hitmark IR

Hitmark TR

Hitmark Bearing

IR Loud

Bearing Loud

Index Time Type Serial ClassificatBand_0: I Limit

0 ######## 30206_27 81015 i .O. 19.777 5000

1 ######## 30206_27 81015 i.O. 121.137 5000

2 ######## 30206_27 81015 n.i.O. 140.355 5000

3 ######## 30206_27 81015 i .O. 84.145 5000

4 ######## 30206_27 81015 i .O. 68.856 5000

5 ######## 30206_27 81015 i.O. 115.083 5000

6 ######## 30206_27 81015 i.O. 217.688 5000

7 ######## 30206_27 81015 i .O. 54.993 5000


19/26

Data collection: Sample of 50 bearings is collected from rejected MVR lot. Then these 50

bearings are again tested on MVR and vibration data of these 50 bearings are collected

from MVR database. These rejected bearings are also tested manually by opening them,

because MVR can give false rejection. So after validation of data a Pareto chart of the data

is plotted and dominant band are find out.


20/26

0

20

40

60

80

100

120

NOISEPEAK

NOISERMS

SK1MIX7

SK2MIX7

NOISE4

SK1MIX5

SK1MIX4

SK2MIX4

SK2MIX5

NOISE5

NOISE7

SK1MIX8

SK2MIX8

NOISE8

SK1MIX6

SK24

SK2MIX3

NOISE6

SK25

SK2MIX6

NOISE3

SK1MIX3

NOISEHIGH

SK15

IRFPEAK

SK28

SK17

SK1MIX9

SK23

SK26

SK27

SK2MIX9

NOISE9

NOISEMEDIUM

TRFPEAK

SK10

SK11

SK12

SK13

SK14

SK16

SK18

SK19

SK1MIX0


21/26

0

5

10

15

20

25

30

35

40

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7

SK1 MIX SK2 MIX NOIS

Frequency of Defect


22/26

The frequency chart and the Pareto chart show that the Noise Peak and Noise Rms bands

have the highest frequency of crossing the limiting value followed by the band no. 4,5,7,8 inthe Mix region.

These 50 rings were visually inspected for surface defects and the rings were sorted

category wise according to the type of defect. The rings were sorted into those having

honing defects, those having dents. There were some severe unusual types of surface

defects observed. These defects were probably due to sudden stopping of the grinding

wheel. Out of 50, 26 rings were found to have honing defects, 34 rings were found to have

dents or scratches. Out of 50, 14 rings had severe surface defects. These defects can be

seen in the following photographs:


23/26

Figure 2: Photographs of defective inner rings of 30206 type of TRB

7. Appendix

Tapered roller bearing (TRB):

Vibration Analysis-

Vibration analysis is used to detect the early precursors to machine failure, allowing

machinery to be repaired or replaced before an expensive failure occurs. All rotating

equipment vibrates to some degree, but as older bearings reach the end of their product life

they begin to vibrate more dramatically, and in distinct ways. So monitoring of equipment

allows these signs of wear and damage to be identified well before the damage becomes

an expensive problem.

Noise-


24/26

Noise means any unwanted sound. In both analog and digital electronics,noiseis an

unwanted perturbation to a wanted signal; it is called noise as a generalisation of the

audible noise heard when listening to a weakradiotransmission.

Waviness-

Waviness is the measure of the more widely spaced component ofsurface texture. It is a

broader view ofroughnessbecause it is more strictly defined as "the irregularities whose

spacing is greater than the roughness sampling length". It can occur from machine or

workdeflections, chatter,residual stress,vibrations, orheat treatment

MVR-

MVR is a vibration testing machine used for bearing. When inner ring passes through MVR

then it shows band values for around 62 parameters. First we have to feed the limiting

value of each parameter then if the actual value crosses the limiting value then thecorresponding band is displayed as rejected band.

Mix-

Inner ring and tapered roller are two parts responsible for vibration in bearing. Mix is the

vibration generated by both inner ring and tapered roller.

Crest-

The crest factor or peak-to-average ratio (PAR) or peak-to-average power ratio (PAPR) is a

measurement of awaveform, calculated from thepeak amplitudeof the waveform divided

by theRMSvalue of the waveform.

Rms-

Root Mean Square The measure of energy displayed in a frequency spectrum. It is

derived by squaring each spectrum line, taking their average, then taking the square root of

average. It also equals to (Peak)*0.707.

Peak

The maximum positive amplitude shown on a sine curve. It is one of the 62 bands which

are checked by the MVR. It represents dirt or hit marks in the inner ring.
http://en.wikipedia.org/wiki/Soundhttp://en.wikipedia.org/wiki/Noise_(electronics)http://en.wikipedia.org/wiki/Noise_(electronics)http://en.wikipedia.org/wiki/Noise_(electronics)http://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Surface_roughnesshttp://en.wikipedia.org/wiki/Surface_roughnesshttp://en.wikipedia.org/wiki/Surface_roughnesshttp://en.wikipedia.org/wiki/Deflectionhttp://en.wikipedia.org/wiki/Deflectionhttp://en.wikipedia.org/wiki/Deflectionhttp://en.wikipedia.org/wiki/Residual_stresshttp://en.wikipedia.org/wiki/Residual_stresshttp://en.wikipedia.org/wiki/Residual_stresshttp://en.wikipedia.org/wiki/Vibrationhttp://en.wikipedia.org/wiki/Vibrationhttp://en.wikipedia.org/wiki/Vibrationhttp://en.wikipedia.org/wiki/Heat_treatmenthttp://en.wikipedia.org/wiki/Heat_treatmenthttp://en.wikipedia.org/wiki/Heat_treatmenthttp://en.wikipedia.org/wiki/Waveformhttp://en.wikipedia.org/wiki/Waveformhttp://en.wikipedia.org/wiki/Waveformhttp://en.wikipedia.org/wiki/Peak_amplitudehttp://en.wikipedia.org/wiki/Peak_amplitudehttp://en.wikipedia.org/wiki/Peak_amplitudehttp://en.wikipedia.org/wiki/Root_mean_squarehttp://en.wikipedia.org/wiki/Root_mean_squarehttp://en.wikipedia.org/wiki/Root_mean_squarehttp://en.wikipedia.org/wiki/Root_mean_squarehttp://en.wikipedia.org/wiki/Peak_amplitudehttp://en.wikipedia.org/wiki/Waveformhttp://en.wikipedia.org/wiki/Heat_treatmenthttp://en.wikipedia.org/wiki/Vibrationhttp://en.wikipedia.org/wiki/Residual_stresshttp://en.wikipedia.org/wiki/Deflectionhttp://en.wikipedia.org/wiki/Surface_roughnesshttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Noise_(electronics)http://en.wikipedia.org/wiki/Sound


25/26

Grinding-

Grinding is anabrasive machiningprocess that uses a grinding wheel as thecutting tool.

Grinding can produce very fine finishes and very accurate dimensions; yet in mass

production contexts it can also rough out large volumes of metal quite rapidly. Grinding is a

subset of cutting, as grinding is a true metal-cutting process.

Honing-

Honing is anabrasive machiningprocess that produces aprecision surfaceon ametalwork

piece by scrubbing anabrasivestone against it along a controlled path. Honing is primarily

used to improve the geometric form of a surface, but may also improve thesurface texture.

Different types of honing is-

Track/Raceway honing

Spherical honing

OD through-feed honing (taper and straight)

Flat honing

Bore honing

Dent-

Dent is a slight depression, or small notch or hollow, made by a blow or by pressure; anindentation. It may be generated during the manufacturing or finishing processes or at

points on the channel where there is a possibility of severe impact. It contributes

significantly to MVR rejection.

Dirt-

Dirt is unclean matter. Common types of dirt include:

dust a general powder of organic or mineral matter

filth foul matter such as excrement

grime a black, ingrained dust such assoot

soil the mix of clay, sand and humus which lies over the bedrock

Dirt is interpreted as peak noise and leads to false rejection in the MVR.

.

Conclusion:
http://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Cutting_tool_(machining)http://en.wikipedia.org/wiki/Cutting_tool_(machining)http://en.wikipedia.org/wiki/Cutting_tool_(machining)http://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Surface_integrityhttp://en.wikipedia.org/wiki/Surface_integrityhttp://en.wikipedia.org/wiki/Surface_integrityhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Abrasivehttp://en.wikipedia.org/wiki/Abrasivehttp://en.wikipedia.org/wiki/Abrasivehttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Flat_honinghttp://en.wikipedia.org/wiki/Flat_honinghttp://en.wikipedia.org/wiki/Dusthttp://en.wikipedia.org/wiki/Dusthttp://en.wikipedia.org/wiki/Filthhttp://en.wikipedia.org/wiki/Filthhttp://en.wikipedia.org/wiki/Grimehttp://en.wikipedia.org/wiki/Grimehttp://en.wikipedia.org/wiki/Soothttp://en.wikipedia.org/wiki/Soothttp://en.wikipedia.org/wiki/Soothttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soothttp://en.wikipedia.org/wiki/Grimehttp://en.wikipedia.org/wiki/Filthhttp://en.wikipedia.org/wiki/Dusthttp://en.wikipedia.org/wiki/Flat_honinghttp://en.wikipedia.org/wiki/Surface_texturehttp://en.wikipedia.org/wiki/Abrasivehttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Surface_integrityhttp://en.wikipedia.org/wiki/Abrasive_machininghttp://en.wikipedia.org/wiki/Cutting_tool_(machining)http://en.wikipedia.org/wiki/Abrasive_machining


26/26

8. References

PS diary

http://www.skf.com/portal/skf_in/home/about?contentId=149396&la

ng=en http://www.skf.com/portal/skf_in/home/products?contentId=149391

&lang=en

http://en.wikipedia.org/wiki/SKF

http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-

US:official&client=firefox-a&um=1&ie=UTF-

8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672

http://www.google.com/search?um=1&hl=en&client=firefox-

a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sig

ma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4

335l0l4l4l0l0l0l0l148l280l0.2l2

http://www.mydigitallife.info/combine-and-merge-multiple-

documents-in-microsoft-office-word-2007/

http://en.wikipedia.org/wiki/Waviness

http://en.wikipedia.org/wiki/Bearing_%28mechanical%29

http://en.wikipedia.org/wiki/Pareto_chart

http://en.wikipedia.org/wiki/Pareto_distribution

http://en.wikipedia.org/wiki/Pareto_principle

http://www.google.com/search?q=bearing+defects&oe=utf-

8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-

8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672
http://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://en.wikipedia.org/wiki/SKFhttp://en.wikipedia.org/wiki/SKFhttp://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://en.wikipedia.org/wiki/Wavinesshttp://en.wikipedia.org/wiki/Wavinesshttp://en.wikipedia.org/wiki/Bearing_%28mechanical%29http://en.wikipedia.org/wiki/Bearing_%28mechanical%29http://en.wikipedia.org/wiki/Pareto_charthttp://en.wikipedia.org/wiki/Pareto_charthttp://en.wikipedia.org/wiki/Pareto_distributionhttp://en.wikipedia.org/wiki/Pareto_distributionhttp://en.wikipedia.org/wiki/Pareto_principlehttp://en.wikipedia.org/wiki/Pareto_principlehttp://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=bearing+defects&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://en.wikipedia.org/wiki/Pareto_principlehttp://en.wikipedia.org/wiki/Pareto_distributionhttp://en.wikipedia.org/wiki/Pareto_charthttp://en.wikipedia.org/wiki/Bearing_%28mechanical%29http://en.wikipedia.org/wiki/Wavinesshttp://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.mydigitallife.info/combine-and-merge-multiple-documents-in-microsoft-office-word-2007/http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&biw=1366&bih=672&tbm=isch&sa=1&q=skf+six+sigma&oq=skf+six+sigma&aq=f&aqi=&aql=&gs_sm=e&gs_upl=3663l4335l0l4l4l0l0l0l0l148l280l0.2l2http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://www.google.com/search?q=skf&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1366&bih=672http://en.wikipedia.org/wiki/SKFhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/products?contentId=149391&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=enhttp://www.skf.com/portal/skf_in/home/about?contentId=149396&lang=en

Date post:	05-Apr-2018
Category:	Documents
Upload:	gaurav-mittal
View:	217 times
Download:	0 times

Report Quality

Documents