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DEPARTMENT OF PRODUCTION ENGINEERING BIT, MESRA, RANCHI B:E (VIII-SEMESTER) QUALITY ENGINEERING (PE-8141) MODULE-I 1. (a) Distinguish clearly between quality control and inspection. (b) Explain briefly the advantages by maintaining good quality. (c) What do you understand by statistical quality control? Point out its usefulness in industry. 2. (a) When is a manufacturing process is said to be in a state of statistical control? (b) Discuss the importance of control charts in a manufacturing unit. 3. (a) Explain briefly, why statistical quality control is more applicable in a mass production industry? (b) What are the objectives of statistical quality control? 4. (a) Describe the limitations of statistical quality control. (b) Discuss the benefits of statistical quality control. 5. Describe briefly the following with suitable examples: (a) Control (b) Quality Control (c) Statistical Quality Control 6. What are the different statistical tools and techniques for quality control and improvement? Discuss briefly with suitable examples. 7. What do you understand by the following? Explain with suitable examples. (a) Mean (b) Median (c) Mode (d) Standard Deviation (e) Variance 8. Differentiate between following: (a) Grouped and Ungrouped Data (b) Measure of Central Tendency and Measure of Dispersion (c) Skewness and Kurtosis (d) Population and Sample

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Page 1: Quality Engg

DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE-I

1. (a) Distinguish clearly between quality control and inspection.(b) Explain briefly the advantages by maintaining good quality.(c) What do you understand by statistical quality control? Point out its usefulness in industry.

2. (a) When is a manufacturing process is said to be in a state of statistical control? (b) Discuss the importance of control charts in a manufacturing unit.3. (a) Explain briefly, why statistical quality control is more applicable in a mass production

industry? (b) What are the objectives of statistical quality control?4. (a) Describe the limitations of statistical quality control. (b) Discuss the benefits of statistical quality control.5. Describe briefly the following with suitable examples: (a) Control (b) Quality Control (c) Statistical Quality Control6. What are the different statistical tools and techniques for quality control and

improvement? Discuss briefly with suitable examples.7. What do you understand by the following? Explain with suitable examples. (a) Mean (b) Median (c) Mode (d) Standard Deviation (e) Variance8. Differentiate between following: (a) Grouped and Ungrouped Data (b) Measure of Central Tendency and Measure of Dispersion (c) Skewness and Kurtosis (d) Population and Sample9. Explain the following with suitable sketches: (a) Frequency Histogram (b) Relative Frequency Histogram (c) Cumulative Frequency Histogram (d) Relative Cumulative Frequency Histogram (e) Bar Graph (f) Frequency Polygon (g) Ogive10. Calculate the arithmetic average, the standard deviation, variance and coefficient of

variation from the following data: 14.2, 15.6, 13.7, 12.9, 13.4, 13.6, 14.0, 15.1, 14.5, 15.011. The average sub-group of 25 items was calculated to be 78.4. It was later on discovered

that one reading was misread to be 69 instead of the correct value of 96. Calculate the correct average.

12. What can one tell about the percentage of cases outside the limit in a frequency distribution?

(a) If it is known that the distribution is approximately normal?

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(b) If it is known that the distribution satisfies the Camp-Meidell inequality? (c) If nothing at all is known about the form of distribution?13. (a) What do you understand by dispersion? Discuss the relative merits of various

measures of dispersion. (b) Why standard deviation is considered superior measure of dispersion over the other

methods?14. Enumerate briefly the following with suitable sketches: (a) Various characteristics of the frequency distribution graphs. (b) Relationship among various measures of central tendency. (c) Relationship among various measures of dispersion.15. (a) What do you understand by ‘Standardized Normal Value (Z)’? (b) Explain its significance for normal distributed data in statistical quality control with

suitable sketches.16. The mean value of the weight of a particular brand of cereal for the past year is 0.297 kg

with a standard deviation of 0.024 kg. Assuming a normal distribution, find the following percentage of the data that:

(a) Falls below the lower specification limit of 0.274 kg. (b) Falls above 0.347 kg. (c) Falls in between 0.286 and 0.338 kg.17. A cold-cereal manufacturer wants 1.5% of the product to be below the weight

specification of 0.567 kg. If the data are normally distributed and the standard deviation of the cereal filling machine is 0.018 kg. What mean weight is required?

18. What is ‘Central Limit Theorem’? What is the importance of ‘Standardized Normal Value (Z)’ in SQC? Explain with suitable example.

19. Quality control is a system of inspection, analysis and action applied to a manufacturing process. Discuss this with suitable example.

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DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

ASSIGNMENT

1. A machine was set to produce a diameter 12 ± 0.05 mm. It ran for approximately seven hours, making one piece-a-minute. The whole output was checked with the results tabulated as given below in the table.

(a) Plot a histogram and a frequency distribution curve.(b) Comment upon the shape of the curves obtained.

MeasuredDiameter

11.97 11.98 11.99 12.00 12.01 12.02 12.03 12.04 12.05 12.06 12.07 12.08

No. of Pieces

1 7 49 103 102 43 20 38 39 15 2 1

2. An age analysis of factory workers revealed the following data as shown in the table. Calculate the mean and median. Draw a histogram of the data and indicate on it both mean and median.Ages 16-19 20-29 30-39 40-49 50-59 60-69

frequencies 15 46 49 32 28 14 3. The following grouped frequency distribution describes the measurement of contents

of 200 containers (in c.c). Data is given below in the table.(a) Draw a histogram for these data and thus determine its modal volume.(b) Draw the cumulative frequency curve and estimate from it the median volume.

Contents(c.c)

6 & less than 7

7 & less than 8

8 & less than 9

9 & less than 10

10 & less than 11

11 & less than 12

No. of containers

2 6 49 121 19 3

4. From a certain frequency distribution consisting of 18 observations, the mean and the standard deviation were found to be 7 and 4 respectively. But on comparing the original data it was found that a figure 12 was misread as 21 in the calculation. Calculate the correct mean and standard deviation.

5. In a moderately asymmetrical distribution the mode and the mean are 32.1 and 35.4 respectively. Calculate the median.

6. (a) State some of the characteristics of normal distribution with suitable sketch.(b) The mean value of modulus of rupture of large number of test specimens has been found to be 5600 kg/cm2. Assuming the distribution to be approximately normal and standard deviation to be 840 find out what fraction or percentage of the specimen the modulus of rupture will lie between (i) 5000 and 6000 (ii) Above 4000 (iii) Below 3500?7. Classify the following data as to whether they are discrete or continuous. Give reasons for it. (a) Weekly number of accidents.

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(b) Percentage of tanks with discharge silver solders leaks.(c) Tensile strength of cotton yarn in kg/cm2

(d) Monthly number of machines rejected.(e) Diameters of metal knobs.

8. The production of radar component is checked by examining samples of 4. The table below shows number of defectives found in 200 samples. Calculate following:(a) The mean number of defectives(b) The standard deviation of the number of defectives.(c) The median and mode.

9. The frequency distribution given below shows the percent of organic sulfur in Illinois No. 5 coal. Determine the modal cell and sample mean and standard deviation.Cell

Midpoint0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5

Frequency(Samples)

1 16 12 10 3 12 20 12 14 6 4

10. In the precision grinding of a complicated part, it is more economical to rework the part than to scrape it. Therefore, it is decided to establish the rework percentage at 12.5%. Assuming normal distribution of the data, a standard deviation of 0.01 mm, and an upper specification limit of 25.38 mm, determine the process center.

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DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE-II

1. What is the difference between ‘Assignable Causes’ and ‘Chance Causes’ of variation? What is the significance of this difference in statistical quality control? How will these causes be identified in practice?

2. (a) What do you understand by control charts? Explain briefly with suitable example. (b) Are ‘Control Limits’ different from ‘Specification Limits’? Give justification. 3. Why ‘Dual Charting’ technique is always used in an industry for quality control? Explain with the example of simultaneous use of and R charts.4. (a) Discuss briefly the complete procedure of control chart technique with suitable example. (b) How are ‘Revised Control Limits’ different from ‘Trial Control Limits’?5. (a) What are the basic difference between control charts for variable and attributes? (b) Enumerate briefly the purpose of variable control charts.6. (a) What the two methods used for selection of rational subgroups from a population? Explain briefly.(b) Why lower control limit in R chart is practically kept at zero? Explain with suitable sketch.(c) Why the S chart should be used instead of R chart, when a subgroup size exceeds ten? Explain briefly.7. Comment, “The central line and control limits of a control chart are more representative of the population, when out-of-control points with assignable causes are discarded”.8. What do you understand by ‘Process Capability’? Discuss in detail giving suitable example. How does the process capability can be established by control charting technique?9. Explain in detail with suitable example the formulation and use of chart (control chart for averages).10. Explain in detail with suitable example the formulation and use of R chart (control chart for ranges).11. Explain in detail with suitable example the formulation and use of S chart (control chart for standard deviation).12. What do you understand by ‘Attribute’? Why does control charts for variables cannot be used for SQC of attributes? Explain briefly.13. (a) Write brief note on control charts for proportion or fraction defective (P-chart). Enumerate briefly its major objectives.(b) Why does the lower control limit of a P-chart is kept at zero? Explain with suitable example.14. Explain in brief the general procedure and use of P-chart (charts for proportion or fraction defective) for constant subgroup size using a suitable example.16. (a) Enumerate briefly the purpose of using control charts for number of defects.(b) Why does the lower control limit of a C-chart (charts for number of defects) is kept at zero? Explain with suitable example.17. (a) Enumerate briefly the purpose of using control charts for number of defects.

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(b) What are the various practical benefits accrued to producers and consumers, when a process is in control.(c) On what conditions does one can infer that the process is out-of-control? Explain with suitable example with at least two such patterns.18. Control charts for and R are maintained on a certain dimension of a manufactured part. The group size is 4. The values of X bar and R are computed for each group. After 20 subgroups, ∑X=41.34 and ∑R=0.32. Compute the values of 3 limits for the and R charts assuming that the process is in statistical control. Given d2 = 2.059, A2 = 0.73, D1 = 0 and D4

=2.28.

DEPARTMENT OF PRODUCTION ENGINEERING

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BIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

ASSIGNMENT1. Control charts for and R are to be established on a certain dimension part, measured

in mm. Data were collected in subgroup sizes of 6 are given below. Determine the trial central line and control limits. Assume assignable causes and revise the central line and limits. Show the charts graphically also.

SubgroupNo.

RSubgroup

No.R

1 20.35 0.34 14 20.41 0.362 20.40 0.36 15 20.45 0.343 20.36 0.32 16 20.34 0.364 20.65 0.36 17 20.36 0.375 20.20 0.36 18 20.42 0.736 20.40 0.35 19 20.50 0.387 20.43 0.31 20 20.31 0.358 20.37 0.34 21 20.39 0.389 20.48 0.30 22 20.39 0.3310 20.42 0.37 23 20.40 0.3211 20.39 0.29 24 20.41 0.3412 20.38 0.30 25 20.40 0.3013 20.40 0.33

2. Control charts for and S are to be established on the Brinell hardness of hardened tool steel in kg per square mm. Data were collected in subgroup sizes of 8 are given below. Determine the trial central line and control limits. Assuming assignable causes for the out-of-control points, determine the revised central line and limits. Show the charts graphically also.Subgroup

No.S

SubgroupNo.

S

1 540 26 14 551 242 534 23 15 522 293 545 24 16 579 264 561 27 17 549 285 576 25 18 508 236 523 50 19 569 227 571 29 20 571 288 547 29 21 563 339 584 23 22 561 2310 552 24 23 548 2511 541 28 24 556 2712 545 25 25 553 2313 546 26

3. Rework problems 1 and 2 assuming a subgroup size of 3.

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4. Control charts for X and R are kept on the weight in kilograms of a color pigment for a batch process. After 25 subgroups, with a subgroup size of 4, the following data was established ΣX=52.08 kg and ΣR=11.82 kg. Assuming the process is in a state of control, compute the X and R chart central line and control limits for the next production period.

5. Control charts for X and S are maintained on the resistance in ohms of an electric part. The subgroup size is 6. After 25 subgroups, the following data was established ΣX=2046.5 and ΣS=17.1. If the process is in statistical control, what are the central line and control limits?

6. A new process is started and the sum of the sample standard deviations for 20 subgroup of size 4 is 600. If the specifications are 700+ 80, what is the process capability index? What actions would you recommend?

7. Determine the trial central line and control limits for a P-chart using the data in the table. If there are any out of control points, assume an assignable cause and determine the revised central line and control limits. Draw the control chart also.Subgroup Number

Number Inspected

Number Detective

Subgroup Number

Number Inspected

Number Detective

1 300 3 11 300 62 300 6 15 300 73 300 4 16 300 44 300 6 17 300 55 300 20 18 300 76 300 2 19 300 57 300 6 20 300 08 300 7 21 300 29 300 3 22 300 310 300 0 23 300 611 300 6 24 300 112 300 9 25 300 813 300 5

8. In filing bags of nitrogen fertilizer, it is desired to hold the average overfill to as low a value as possible. The lower specification limit is 22.00 kg, the population means weight of the bags is 22.73 kg and the population standard deviation is 0.80 kg. What percent of the bags contain less than 22 kg? If it is permissible for 5% of the bags to be below 22 kg. What would be the average weight? Assume a normal distribution.

9. A company that manufactures oil seals found the population mean to be 49.15 mm, the population standard deviation to be 0.51 mm and the data to be normally distributed. If the ID of the seat is below the lower specification limit of 49.80 mm, the seal is scarped. (a) What percent of the seals are reworked? (b) What percent are scraped? (c) For various reasons the process average is changed to 48.50 mm. With this new mean or process center, what percent of the seals are reworked? What percent are scraped? If rework is economically feasible, is the change in the process center a wise decision?

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10. The data in the table give the count of defects in double pedestal office desk for the month of January. What control limits and central line are recommended for the control chart for February? Determine the revised central line and control limits. Draw the control chart also.

Serial number Count of Defects Serial Number Count of Defects301 8 314 17302 19 315 14303 14 316 9304 18 317 7305 11 318 15306 16 319 22307 8 320 19308 15 321 38309 21 322 12310 8 323 13311 23 324 5312 10 325 2313 9 326 16

11. Fifty motor generators are inspected per day. The best estimate of the population fraction defective is 0.076. Determine the central line and control limits. On a particular day 5 defective generators were discovered. Is this in control or out of control?

12. Write a computer program for following:(a) -chart(b) R-chart(c) S-chart(d) P-chart(e) C-chart

Test Books Recommended:1. Statistical Quality Control M. Mahajan, Dhanpat Rai & Sons2. Statistical Quality Control and Reliability D.H.Besierfield, Prentice Hall

Page 10: Quality Engg

DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)MODULE III

1. (a) Differentiate between 100% inspection and statistical sampling techniques using suitable example.(b) What are the situations when acceptance sampling of the product is most likely used?

2. (a) Enumerate briefly the advantages and disadvantages of acceptance sampling technique.(b) Comment, “Components of a sample should be selected randomly from a lot”.(c) What are the essential conditions for the formation of lots during sampling? Discuss.

3. (a) What do you understand by “OC(Operating Characteristics)”? Explain with suitable example.(b) What is the use of OC curves in inspection? Describe.

4. Explain the various OC curve characteristics? Give suitable example.5. (a) Explain the characteristics of acceptance sampling.

(b) Describe the procedure of sampling inspection briefly using a suitable example.

6. Write short notes on following:(a) Sampling Inspection(b) Limitations of sampling(c) Application of sampling inspection

ASSIGNMENT1. Write short notes on the following:(a) Producers’ Risk (b) Consumers’ Risk(c) Average Outgoing Quality

(AOQ)(d) Average Sample Number

(e) Average Total Inspection (f) Acceptable Quality Level (AQL)

2. Construct an OC curve for the single sampling plan =9000, n=110 and c=3. Use about seven points.

3. Determine the equation for the OC curve for the sampling plan N=10,000, n1=200, c1=2, r1=6, n2=350, c2=6 and r2=7. Construct the curve using about seven points.

4. Determine the equation for the OC curve for the following sampling plans:(a) N=500, n1=50, c1=0, r1=3, n2=2 and r2=3.(b) N=6000, n1=80, c1=2, r1=4, n2=160, c2=5 and r2=6(c) N=22,000, n1=260, c1=5, r1=9, n2=310, c2=8 and r2=9

Text Books Recommended:1. Statistical Quality Control M. Mahajan, Dhanpat Rai & sons2. Statistical Quality Control and Reliability D.H. Besterfield, Prentice Hall

Page 11: Quality Engg

DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE IV1. (a) What are single, double and multiple acceptance sampling plans? Explain with

suitable examples.(b) Comment, “all these acceptance sampling plans may give rise to same results”.

2. (a) Compare in detail the characteristics of single, double and multiple acceptance sampling plans.(b) Single sampling plans gives more information concerning quality level in lots than double sampling and much more than multiple sampling. Why? Explain Briefly.

3. Explain the following with suitable examples:(a) Construction and use of OC curve for single sampling plan.(b) Construction and use of OC curve for double sampling plan.(c) Construction and use of OC curve for multiple sampling plan.

4. Explain in detail the significance of AQL (Acceptable Quality Level) and n(sample size) in selection of a sampling plan from standard sampling plan systems with the help of appropriate example.

5. for a lot size of 2000, an AQL of 0.65 % and an inspection level of III, determine the single sampling plans for normal, tightened and reduced inspection using MIL-STD-105D sampling plan system.

6. For a lot size of 20,000, an AQL of 1.5% and an inspection level of I, determine the multiple sampling plan for normal, tightened and reduced inspection using MIL-STD-105D sampling plan system.

7. For a lot size of 450, an AQL of 4.0% and an inspection level of II, determine the multiple sampling plans for normal, tightened and reduced inspection using MIL-STD-105D sampling plan system.

8. Explain briefly the concept of ‘Sequential Sampling’ plan. How does the plan differs from a multiple sampling plan? Also, illustrate and explain the graphical representation of an item-by-item sequential sampling plan.

9. A unit sequential sampling plan is defined by Pα=0.08, α=0.05, Pβ=0.08 and β=0.10. Determine the equations for the acceptance and rejection line and draw the graphical plan.

ASSIGNMENT1. For c=3, c=6 and c=12, determine the sampling plans for AQL=1.5% and α=0.05.2. If product that is 8.3% defective is accepted 10% of the time, determine the three

sampling plans which meet this criterion, Use c=0, 3 and 7.3. (a) Using MIL-STD-105D sampling plan system, determine the single sampling

plans for the following information:Inspection Level Inspection AQL Lot Size

II Tightened 1.5% 1,400I Normal 65 115

III Reduced 0.40% 160,000III Normal 2.5% 27

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(b) Explain the meaning of the sampling plan determined in third case of the above problem, if (i) 6 defectives are found in the sample, (ii) 8 defectives are found and (iii) 4 defectives are found.4. (a) Using MIL-STD-105D sampling plan system, determine the double sampling

plans for the following information;Inspection Level Inspection AQL Lot Size

I Normal 150 145II Reduced 0.15% 1,150II Tightened 2.5% 65III Reduced 15 8,050III Tightened 0.40% 24,000

(b) Describe the double sampling plan for the fourth case of above problem.5. Using MIL-STD-105D sampling plan system, determine the multiple sampling

plans for the following information:Inspection Level Inspection AQL Lot Size

III Tightened 0.25% 70I Normal 0.25% 12,500

III Reduced 1.5% 3,400

6. Inspection results for the last 8 lots using the single sampling plan of n=225, c=3 are as follows:

Lot 1 1 Defective Lot 5 3 DefectivesLot 2 4 Defectives Lot 6 0 DefectiveLot 3 5 Defectives Lot 7 2 DefectivesLot 4 1 Defective Lot 8 2 Defectives

If normal inspection was used for lot 1, what inspection should be used for lot 9 (after lot 8)?

7. For a unit sequential sampling plan that is defined by Pα=0.05, α=0.08, Pα=0.12 and β=0.15, determine the equations for the acceptance and rejection line. Using these equations, establish a table of the rejection number, acceptance number and number of units inspected. The table can be stopped when the rejection number equals 6. Also, draw the corresponding graphical plan.

8. Write a computer program for:(a) OC curve for single sampling plan(b) OC curve for double sampling plan(c) OC curve for multiple sampling plan(d) Sequential sampling by attributes

Test Books Recommended:1. Statistical Quality Control M.Mahajan, Dhanpat Rai & Sons2. Statistical Quality Control & Reliability D.H. Besterfield, Prentice Hall3. Inspection Quality Control & Reliability S.C.Sharma, Khanna Publishers

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DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE V1. (a) Define ‘Reliability’. Enumerate briefly various factors associated with reliability.

(b) Explain briefly, why now-a-days increased emphasis is given to product reliability?

2. (a) What do you understand by system reliability?(b) Discuss in brief various factors on which product reliability depends?

3. (a) Distinguish between quality and reliability.(b) What is quality assurance? Explain briefly.

4. (a) Explain briefly with suitable figures reliability curves for following distribution.(i) Exponential Distribution(ii) Normal Distribution(iii) Weibull Distribution(iv) Gamma Distribution(v) Beta Distribution(vi) Rayleigh Distribution

(b) What do you understand by ‘Failure Rate’ curve? How ‘failure rate’ is estimated from a test data? How ‘Mean Life’ of components is related to ‘Failure Rate’?

5. Write short notes on following:(a) Reliability Function(b) Hazard Rate(c) Failure Rate(d)Mean Time to Failure (MTTF)(e) Reliable Life

6. (a) Draw the ‘Failure Rate’ curves for Exponential, Normal and Weibull Distributions.(b) Draw and explain briefly the typical ‘Life History’ curve of a complexed product for an infinite number of items.

7. What do you understand by system reliability? Derive and explain briefly the reliability of system having components configured in series and parallel.

8. (a) Explain briefly the terms ‘Reliability’, ‘Maintainability’ and ‘Availability’.(b) Distinguish between ‘Reliability’ and ‘Unreliability’.

ASSIGNMENT1. A system has four components A,B,C and D with reliability values of 0.98, 0.89, 0.94

and 0.95 respectively. If the components are in series, what is the system reliability? If the component B is changed to three parallel components each having the same reliability, what will be the new system reliability?

2. (a) If the mean life is 52 hours, what is the failure rate?(b) Determine the failure rate for a 150-h test of 9 items. Where three items failed at 5, 76 and 135 hours. What is the mean Life?

3. Determine the probability of failure-free performance for t= 15,000 hours of a tractor component which usually fails by wear out. Life test have revealed that its life is governed by normal distribution with parameter μ=40,000 hours and δ=10,000 hours. Also, assess the 80% life of the component.

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4. The life expectancy of roller bearings can be defined by a Weibull distribution. If, for a particular set of bearings, m=1.5 and θm=107 hours, estimate the probability of failure – free performance for t=104 hours.

5. In an accelerated test to determine the time to failure of friction clutches, the results showed the following data:

Minimum Duration 5 hours Maximum Duration 10 hoursMean Duration 7 hours Cofficient of variation 0.1

Assuming a beta distribution, determine the probability that the clutch during the accelerated test will fail within 9 hours.

6. Consider two links A and B connected in series and transmitting a force of 5000 N. If the probability of failure of catch link under this force is 0.05, determine the system reliability. Also, determine the system reliability, when the links are connected in parallel.

7. In a test of electric fuses, 100 fuses fail in five hours. The failure was recorded as follows:Hrs. 1 2 3 4 5No. Failed 20 15 25 20 20

Calculate failure rate and hazard rate for this test.8. An electronic system has a M.T.B.F. of 1000 hours and a M.T.T.B. of 40 hours, what

is availability?9. At an electric generating system the reliability and failure rate of each of the units in

the system is given below:Units Furnace Boiler Chimney Super

HeaterTurbine Generator

Reliability 0.6 0.8 0.9 0.9 0.85 0.89Failure Rate

0.008 0.012 0.012 0.004 0.003 0.015

Find the total reliability of the power station, and its failure rate?Text Books Recommended:1. Mechanical Reliability L.S. Srinath, East- West Press2. Statistical Quality Control and Reliability D.S. Besterfield, Prentice Hall3. Inspection Quality Control & Reliability S.C. Sharma, Khanna Publishers

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DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE VI1. Define quality and discuss briefly various factors affecting quality.2. What do you understand by cost of poor quality? Briefly discuss the elements of poor

quality costs.3. Explain briefly ISO-9000 Quality System of standards with its major objectives.4. (a) Explain briefly various costs associated with quality

(b) Enumerate briefly various characteristics and benefits of implementing ISO 9000 quality system of standards in any organization.

5. (a) Briefly explain the concept of ‘Quality Circle’ in any organization. What do you understand by ‘Quality Loop’?(b) What is quality audit as per ISO quality system specifications? Explain briefly.

6. (a) What is a ‘Six Sigma’ concept? Give examples where this can be used.(b) How does one can go about implementing ‘Six Sigma’ project? Explain briefly.

ASSIGNMENT1. Briefly discuss the following:

(a) Internal and External Failure costs of a component.(b) Quality control and Quality Improvement(c) Quality costs and cost of Quality.

2. (a) What are the two misconceptions that exist with regard to ISO 9000?(b) Write a brief note on as what steps to follow when an organization goes for implementation of ISO 9000?(c) Where are these applicable ISO 9001, 9002 AND 9003?(d) What is QS 9000?

3. Six sigma uses the concept of ‘Critical to Quality (CTO)’ characteristics. Explain.4. What are the six themes of ‘Six Sigma’?Text Books Recommended:1. Total Quality Management D.H. Besterfield, Prentice Hall2. Inspection Quality Control & Reliability S.C. Sharma, Khanna Publishers3. The Six Sigma Way P.S. Pande, Tata McGraw Hill

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DEPARTMENT OF PRODUCTION ENGINEERINGBIT, MESRA, RANCHIB:E (VIII-SEMESTER)

QUALITY ENGINEERING (PE-8141)

MODULE VII1. (a) Explain the concept of ‘total Quality Control’

(b) Comment, “Total Quality control strategy is customer centric”2. Enumerate briefly the 14- point theory of Dr. W. Edwards Deming for quality

improvement3. How does excellent quality culture can be established in any organizations with the

help of total quality control strategy?4. (a) Define the terms: Internal Customer and External Customer.

(b) Is the main concern of most customers, the price of the product or service? Explain.

5. (a) Why ‘employee Involvement’ is important to Total Quality management? Discuss.(b) What benefits a firm can derive from ‘Total Employee Involvement’?

ASSIGNMENT1. Enumerate briefly the ‘Total Quality Management (TQM)’ approach to achieve ‘Total

Quality control’ in any organization.2. Comment, “Globalization of market evolved quality as a critical parameter for

excellent by any firm”.3. Define the following terms:

(a) Performance(b) Motivation(c) Empowerment

4. Write a plan to implement ‘Total quality Management’ in a technical college or institution.

5. Design a customer satisfaction questionnaire for a technical college or institution.Text Books Recommended:1. Total Quality Management D.H. Besterfield, Prentice Hall2. Inspection Quality Control & Reliability S.C. Sharma, Khanna Publishers