Question & Answer

What is the difference between dependent and independent demand for products?

What are the product categories usually listed in the master production schedule?

How does aggregate planning differ from the master production scheduling?

What is meant by the term make-to-stock production?

There are 19 correct answers in the following multiple choice questions (some questions have multiple

answers that are correct). To attain a perfect score on the quiz, all correct answers must be given. Each

correct answer is worth 1 point. Each omitted answer or wrong answer reduces the score by 1 point, and

each additional answer beyond the correct number of answers reduces the score by 1 point. Percentage

on the quiz is based on the total number of correct answers.

40.1 The manufacturing engineering department in an organization is best described as which one of the

following: (a) branch of the sales department, (b) concurrent engineers, (c) management, (d)

product designers, (e) production supervisors, or (f) technical staff function?

40.2 Which of the following are the usual responsibilities of the manufacturing engineering department

(four best answers): (a) advising on design for manufacturability, (b) facilities planning, (c)

marketing the product, (d) plant management, (e) process improvement, (f) process planning, (g)

product design, (h) solving technical problems in the production departments, and (i) supervision of

production workers?

40.3 Which of the following are considered basic processes, as opposed to secondary processes (four

correct answers): (a) annealing, (b) anodizing, (c) drilling, (d) electroplating, (e) forward hot

extrusion to produce aluminum bar stock, (f) impression die forging, (g) rolling of sheet steel, (h)

sand casting, (i) sheet-metal stamping, (j) spot welding, (k) surface grinding of hardened steel, (l)

tempering of martensitic steel, and (m) turning?

40.4 Which of the following would be considered secondary processes, as opposed to basic processes

(four correct answers): (a) annealing, (b) arc welding, (c) drilling, (d) electroplating, (e) extrusion to

produce steel automotive components, (f) impression die forging, (g) painting, (h) plastic injection

molding, (i) rolling of sheet steel, (j) sand casting, (k) sheet-metal stamping, (l) sintering of pressed

ceramic powders, and (m) ultrasonic machining?

40.5 Which of the following are operations to enhance physical properties (three correct answers): (a)

annealing, (b) anodizing, (c) die casting, (d) drilling, (e) electroplating, (f) rolling of nickel alloys,

(g) sheet metal drawing, (h) sintering of pressed ceramic powders, (i) surface grinding of hardened

steel, (j) tempering of martensitic steel, (k) turning, and (l) ultrasonic cleaning?

40.6 A route sheet is a document whose principal function is which one of the following: (a) continuous

improvement, (b) design for manufacturability, (c) provides authorization for material handlers to

move the part, (d) quality inspection procedure, (e) specifies the process plan, or (f) specifies the

detailed method for a given operation?

40.7 In a make or buy situation, the decision should always be to purchase the component if the vendor’s

quoted price is less than the in-house estimated cost of the component: (a) true or (b) false?

40.8 Which one of the following types of computer-aided process planning relies on parts classification

and coding in group technology: (a) generative CAPP, (b) retrieval CAPP, (c) traditional process

planning, or (d) none of the preceding?

What is meant by the term design for life cycle?

What is concurrent engineering and what are its important components?

Name three of the general principles and guidelines in design for manufacturability.

Identify some of the important factors that should enter into the make or buy decision.

In the make or buy decision, why is it that purchasing a component from a vendor may cost more

than producing the component internally, even though the quoted price from the vendor is lower

than the internal price?

What is a precedence constraint in process planning?

What is the difference between a basic process and a secondary process?

What is a route sheet?

Identify some of the details and decisions that are included within the scope of process planning.

What are the principal activities in manufacturing engineering?

Define manufacturing engineering.

An automated transfer line is to be designed. Based on previous experience, the average downtime

per occurrence = 5.0 min, and the probability of a station failure that leads to a downtime

occurrence p = 0.01. The total work content time = 9.8 min and is to be divided evenly amongst the

workstations, so that the ideal cycle time for each station = 9.8/n. Determine (a) the optimum

number of stations on the line n that will maximize production rate, and (b) the production rate and

proportion uptime for your answer to part (a).

A 12-station transfer line was designed to operate with an ideal production rate = 50 parts/hour.

However, the line does not achieve this rate, since the line efficiency = 0.60. It costs $75/hour to

operate the line, exclusive of materials. The line operates 4000 hours per year. A computer

monitoring system has been proposed that will cost $25,000 (installed) and will reduce downtime

on the line by 25%. If the value added per unit produced = $4.00, will the computer system pay for

itself within one year of operation? Use expected increase in revenues resulting from the computer

system as the criterion. Ignore material costs in your calculations.

A 7-station transfer line has been observed over a 40-hour period. The process times at each

station are as follows: station 1, 0.80 min; station 2, 1.10 min; station 3, 1.15 min; station 4, 0.95

min; station 5, 1.06 min; station 6, 0.92 min; and station 7, 0.80 min. The transfer time between

stations = 6 sec. The number of downtime occurrences = 110, and hours of downtime = 14.5

hours. Determine (a) the number of parts produced during the week, (b) the average actual

production rate in parts/hour, and (c) the line efficiency. (d) If the balancing efficiency were

computed for this line, what would its value be?

A dial-indexing table has 6 stations. One station is used for loading and unloading, which is

accomplished by a human worker. The other five perform processing operations. The longest

process takes 25 sec and the indexing time = 5 sec. Each station has a frequency of failure = 0.015.

When a failure occurs it takes an average of 3.0 min to make repairs and restart. Determine (a)

hourly production rate and (b) line efficiency.

An automated transfer line has 20 stations and operates with an ideal cycle time of 1.50 min.

Probability of a station failure = 0.008 and average downtime when a breakdown occurs is 10.0

minutes. Determine (a) the average production rate and (b) the line efficiency.

The total work content for a product assembled on a manual production line is 48 min. The work is

transported using a continuous overhead conveyor that operates at a speed of 3 ft/min. There are 24

workstations on the line, one-third of which have two workers; the remaining stations each have one

worker. Repositioning time per worker is 9 sec, and uptime efficiency of the line is 95%. (a) What

is the maximum possible hourly production rate if line is assumed to be perfectly balanced? (b) If

the actual production rate is only 92% of the maximum possible rate determined in part (a), what is

the balance efficiency on the line?

Production rate for a certain assembled product is 47.5 units per hour. The total assembly work

content time = 32 minutes of direct manual labor. The line operates at 95% uptime. Ten

workstations have two workers on opposite sides of the line so that both sides of the product can be

worked on simultaneously. The remaining stations have one worker. Repositioning time lost by

each worker is 0.2 min/cycle. It is known that the number of workers on the line is two more than

the number required for perfect balance. Determine (a) number of workers, (b) number of

workstations, (c) the balancing efficiency, and (d) average manning level.

A production line with four automatic workstations (the other stations are manual) produces a

certain product whose total assembly work content time = 55.0 min of direct manual labor. The

production rate on the line is 45 units/hr. Because of the automated stations, uptime efficiency =

89%. The manual stations each have one worker. It is known that 10% of the cycle time is lost due

to repositioning. If the balancing efficiency = 0.92 on the manual stations, find (a) cycle time, (b)

number of workers and (c) workstations on the line. (d) What is the average manning level on the

line, where the average includes the automatic stations?

A manual assembly line has 17 workstations with one operator per station. Total work content time

to assemble the product = 22.2 minutes. The production rate of the line = 36 units per hour. A

synchronous transfer system is used to advance the products from one station to the next, and the

transfer time = 6 seconds. The workers remain seated along the line. Proportion uptime = 0.90.

Determine the balance efficiency.