自动化课后答案ch18cellularmfg-3e-si

1、Cellular Mfg-3e-S 7-19, 21/06, 06/05/07, 08/20/0718.4Chapter 18CELLULAR MANUFACTURINGREVIEW QUESTIONSWhat is grou p tech no logy?Answer: As defi ned in the text, grou p tech no logy is a man ufacturi ng p hilos ophy in which similar p arts are iden tified and grou ped together to take ad

2、va ntage of their similarities in desig n and p roducti on.What is cellular man ufacturi ng?Answer: As defi ned in the text, cellular man ufacturi ng is an app licati on of grou p tech no logy in which dissimilar mach ines or pr ocesses have bee n aggregated into cells, each of which is dedicated to

3、 the p roducti on of a part or pr oduct family or a limited grou p of families.What are the pr oducti on con diti ons un der which grou p tech no logy and cellular man ufacturi ng are most app licable?Answer: The con diti ons ide ntified in the text are (1) the plant curre ntly uses traditi onal bat

4、ch p roducti on and a pr ocess type layout, and this results in much material han dli ng effort, high in-pr ocess inven tory, and long man ufacturi ng lead times; and (2) the p arts can be grou ped into part families.What are the two major tasks that a company must un dertake whe n it impi eme nts g

5、rou p tech no logy?Answer: The two major tasks are (1) ide ntify ing the part families and (2) rearra nging p roducti on machi nes into mach ine cells.14718.5What is a part family?Answer: As defi ned in the text, a part family is a collecti on of p arts that are similar either because of geometric s

6、ha pe and size or because similar pr ocess ing ste ps are required in their man ufacture.18.6What are the three methods for solvi ng the p roblem of grou ping p arts into p art families?Answer: The three methods are (1) visual insp ecti on, (2) p arts classificati on and codi ng, and (3) p roducti o

7、n flow an alysis.18.7What is the differe nee betwee n a hierarchical structure and a cha in-type structure in a classificati on and cod ing scheme?Answer: In a hierarchical structure, also known as a mono code, the interp retati on of each successive symbol depends on the value of the pr eced ing sy

8、mbols. In a cha in-type structure, also known as a po lycode, the interp retati on of each symbol in the seque nee is always the same; it does not depend on the value of p recedi ng symbols.18.8What is p roducti on flow an alysis?Answer: As defined in the text, production flow analysis is a method f

9、or identifying part families and associated mach ine grou pings that uses the in formati on contained on pr oducti on route sheets rather tha n part draw in gs. Work parts with ide ntical or similar rout ings are grou ped into p art families.18.9What are the typ ical objectives whe n impl eme nting

10、cellular man ufacturi ng?Answer: As en umerated in the text, the objectives are to (1) shorte n man ufacturi ng lead times, by reduc ing setu p, work part han dli ng, wait ing times, and batch sizes; (2) reduce work-i n-p rocess inven tory; (3) impr ove quality; (4) simp lify pr oducti on scheduli n

11、g; and (5) reduce setu p times.18.10What is the comp osite part concept, as the term is app lied in grou p tech no logy?Answer: The comp osite part concept is based on p art families. It con ceives of a hyp othetical p art for a give n family that in cludes all of the desig n and man ufacturi ng att

12、ributes of the family .In gen eral, an in dividual p art in the family will have some of the features that characterize the family, but not all of them. The comp osite part p ossesses all of the features.Cellular Mfg-3e-S 7-19, 21/06, 06/05/07, 08/20/07What are the four common GT cell configurations

13、, as identified in the text?18.11Answer: The four GT cell configurations listed in the text are (1) single machine cell, (2) group machine cell with manual handling, (3) group machine cell with semi-integrated handling, and (4) flexible manufacturing cell or flexible manufacturing system.18.12What i

14、s the key machine concept in cellular manufacturing?Answer: The key machine concept acknowledges that there is typically a certain machine in a cell that is more expensive to operate than the other machines or that performs certain critical operations. This machine is referred to as the key machine.

15、 It is important that the utilization of this key machine be high, even if it means that the other machines in the cell have relatively low utilizations. The other machines are referred to as supporting machines, and they should be organized in the cell to keep the key machine busy.18.13What is the

16、difference between a virtual machine cell and a formal machine cell?Answer: Virtual machine cells involve the creation of part families and the dedication of equipment to the manufacture of these part families, but without the physical rearrangement of machines into formal cells. The machines in the

17、 virtual cell remain in their original locations in the factory. Formal machine cells represent the conventional GT approach in which a group of dissimilar machines are physically relocated into a cell that is dedicated to the production of one or a limited set of part.18.14What is the principal app

18、lication of group technology in product design?Answer: As indicated in the text, the principal application of GT in design is to implement a design retrieval system that reduces part proliferation.18.15What is the application of the rank order clustering?Answer: The application of the rank order clu

19、stering in GT is grouping machines into cells based on the partmachine incidence matrix, which in turn is based on route sheets.PROBLEMSParts Classification and Coding18.1Develop the form code (first five digits) in the Opitz System for the part illustrated in Figure P18.1.Solution: L/D = 0.06/0.80

20、= 0.075Digit 1 = 0External shape = smoothDigit 2 = 0Internal shape = smooth, no shape elementDigit 3 = 1Plane surface machining = noneDigit 4 = 0Auxiliary holes, etc., = noneDigit 5 = 0Form code in Opitz system = 0010018.2Develop the form code (first five digits) in the Opitz System for the part ill

21、ustrated in Figure P18.2.Solution: L/D = 2.5/1.5 = 1.667 External shape = stepped, one hole Internal shape = smooth hole Plane surface machining = none Auxiliary holes, etc., = noneDigit 1Digit 2Digit 3Digit 4Digit 511100Form code in Opitz system = 1110018.3Develop the form code (first five digits)

22、in the Opitz System for the part illustrated in Figure P18.3.Solution: L/D = 121/36 = 3.361External shape = stepped both ends with functional groove Internal shape = no holePlane surface machining = noneAuxiliary holes and gear teeth = spur gear.Digit 1 = 2Digit 2 = 6Digit 3 = 0Digit 4 = 0Digit 5 =

23、6Form code in Optiz = 26006Rank Order Clustering18.4 Apply the rank order clustering technique to the part-machine incidence matrix in the following table to identify logical part families and machine groups. Parts are identified by letters, and machines are identified numerically.Parts149Cellular M

24、fg-3e-S 7-19, 21/06, 06/05/07, 08/20/07What are the four common GT cell configurations, as identified in the text?18.11Answer: The four GT cell configurations listed in the text are (1) single machine cell, (2) group machine cell with manual handling, (3) group machine cell with semi-integrated hand

25、ling, and (4) flexible manufacturing cell or flexible manufacturing system.18.12What is the key machine concept in cellular manufacturing?Answer: The key machine concept acknowledges that there is typically a certain machine in a cell that is more expensive to operate than the other machines or that

26、 performs certain critical operations. This machine is referred to as the key machine. It is important that the utilization of this key machine be high, even if it means that the other machines in the cell have relatively low utilizations. The other machines are referred to as supporting machines, a

27、nd they should be organized in the cell to keep the key machine busy.18.13What is the difference between a virtual machine cell and a formal machine cell?Answer: Virtual machine cells involve the creation of part families and the dedication of equipment to the manufacture of these part families, but

28、 without the physical rearrangement of machines into formal cells. The machines in the virtual cell remain in their original locations in the factory. Formal machine cells represent the conventional GT approach in which a group of dissimilar machines are physically relocated into a cell that is dedi

29、cated to the production of one or a limited set of part.18.14What is the principal application of group technology in product design?Answer: As indicated in the text, the principal application of GT in design is to implement a design retrieval system that reduces part proliferation.18.15What is the

30、application of the rank order clustering?Answer: The application of the rank order clustering in GT is grouping machines into cells based on the partmachine incidence matrix, which in turn is based on route sheets.PROBLEMSParts Classification and Coding18.1Develop the form code (first five digits) i

31、n the Opitz System for the part illustrated in Figure P18.1.Solution: L/D = 0.06/0.80 = 0.075Digit 1 = 0External shape = smoothDigit 2 = 0Internal shape = smooth, no shape elementDigit 3 = 1Plane surface machining = noneDigit 4 = 0Auxiliary holes, etc., = noneDigit 5 = 0Form code in Opitz system = 0

32、010018.2Develop the form code (first five digits) in the Opitz System for the part illustrated in Figure P18.2.Solution: L/D = 2.5/1.5 = 1.667 External shape = stepped, one hole Internal shape = smooth hole Plane surface machining = none Auxiliary holes, etc., = noneDigit 1Digit 2Digit 3Digit 4Digit

33、 511100Form code in Opitz system = 1110018.3Develop the form code (first five digits) in the Opitz System for the part illustrated in Figure P18.3.Solution: L/D = 121/36 = 3.361External shape = stepped both ends with functional groove Internal shape = no holePlane surface machining = noneAuxiliary h

34、oles and gear teeth = spur gear.Digit 1 = 2Digit 2 = 6Digit 3 = 0Digit 4 = 0Digit 5 = 6Form code in Optiz = 26006Rank Order Clustering18.4 Apply the rank order clustering technique to the part-machine incidence matrix in the following table to identifylogical part families and machine groups. Parts

35、are identified by letters, and machines are identified numerically.Parts14718.11Answer: The four GT cell configurations listed in the text are (1) single machine cell, (2) group machine cell with manual handling, (3) group machine cell with semi-integrated handling, and (4) flexible manufacturing ce

36、ll or flexible manufacturing system.18.12What is the key machine concept in cellular manufacturing?Answer: The key machine concept acknowledges that there is typically a certain machine in a cell that is more expensive to operate than the other machines or that performs certain critical operations.

37、This machine is referred to as the key machine. It is important that the utilization of this key machine be high, even if it means that the other machines in the cell have relatively low utilizations. The other machines are referred to as supporting machines, and they should be organized in the cell

38、 to keep the key machine busy.18.13What is the difference between a virtual machine cell and a formal machine cell?Answer: Virtual machine cells involve the creation of part families and the dedication of equipment to the manufacture of these part families, but without the physical rearrangement of

39、machines into formal cells. The machines in the virtual cell remain in their original locations in the factory. Formal machine cells represent the conventional GT approach in which a group of dissimilar machines are physically relocated into a cell that is dedicated to the production of one or a lim

40、ited set of part.18.14What is the principal application of group technology in product design?Answer: As indicated in the text, the principal application of GT in design is to implement a design retrieval system that reduces part proliferation.18.15What is the application of the rank order clusterin

41、g?Answer: The application of the rank order clustering in GT is grouping machines into cells based on the partmachine incidence matrix, which in turn is based on route sheets.PROBLEMSParts Classification and Coding18.1Develop the form code (first five digits) in the Opitz System for the part illustr

42、ated in Figure P18.1.Solution: L/D = 0.06/0.80 = 0.075Digit 1 = 0External shape = smoothDigit 2 = 0Internal shape = smooth, no shape elementDigit 3 = 1Plane surface machining = noneDigit 4 = 0Auxiliary holes, etc., = noneDigit 5 = 0Form code in Opitz system = 0010018.2Develop the form code (first fi

43、ve digits) in the Opitz System for the part illustrated in Figure P18.2.Solution: L/D = 2.5/1.5 = 1.667 External shape = stepped, one hole Internal shape = smooth hole Plane surface machining = none Auxiliary holes, etc., = noneDigit 1Digit 2Digit 3Digit 4Digit 511100Form code in Opitz system = 1110

44、018.3Develop the form code (first five digits) in the Opitz System for the part illustrated in Figure P18.3.Solution: L/D = 121/36 = 3.361External shape = stepped both ends with functional groove Internal shape = no holePlane surface machining = noneAuxiliary holes and gear teeth = spur gear.Digit 1

45、 = 2Digit 2 = 6Digit 3 = 0Digit 4 = 0Digit 5 = 6Form code in Optiz = 26006Rank Order Clustering18.11Answer: The four GT cell configurations listed in the text are (1) single machine cell, (2) group machine cell with manual handling, (3) group machine cell with semi-integrated handling, and (4) flexi

46、ble manufacturing cell or flexible manufacturing system.18.12What is the key machine concept in cellular manufacturing?Answer: The key machine concept acknowledges that there is typically a certain machine in a cell that is more expensive to operate than the other machines or that performs certain c

47、ritical operations. This machine is referred to as the key machine. It is important that the utilization of this key machine be high, even if it means that the other machines in the cell have relatively low utilizations. The other machines are referred to as supporting machines, and they should be o

48、rganized in the cell to keep the key machine busy.18.13What is the difference between a virtual machine cell and a formal machine cell?Answer: Virtual machine cells involve the creation of part families and the dedication of equipment to the manufacture of these part families, but without the physic

49、al rearrangement of machines into formal cells. The machines in the virtual cell remain in their original locations in the factory. Formal machine cells represent the conventional GT approach in which a group of dissimilar machines are physically relocated into a cell that is dedicated to the produc

50、tion of one or a limited set of part.18.14What is the principal application of group technology in product design?Answer: As indicated in the text, the principal application of GT in design is to implement a design retrieval system that reduces part proliferation.18.15What is the application of the

51、rank order clustering?Answer: The application of the rank order clustering in GT is grouping machines into cells based on the partmachine incidence matrix, which in turn is based on route sheets.PROBLEMSParts Classification and Coding18.1Develop the form code (first five digits) in the Opitz System

52、for the part illustrated in Figure P18.1.Solution: L/D = 0.06/0.80 = 0.075Digit 1 = 0External shape = smoothDigit 2 = 0Internal shape = smooth, no shape elementDigit 3 = 1Plane surface machining = noneDigit 4 = 0Auxiliary holes, etc., = noneDigit 5 = 0Form code in Opitz system = 0010018.2Develop the

53、 form code (first five digits) in the Opitz System for the part illustrated in Figure P18.2.Solution: L/D = 2.5/1.5 = 1.667 External shape = stepped, one hole Internal shape = smooth hole Plane surface machining = none Auxiliary holes, etc., = noneDigit 1Digit 2Digit 3Digit 4Digit 511100Form code in

54、 Opitz system = 1110018.3Develop the form code (first five digits) in the Opitz System for the part illustrated in Figure P18.3.Solution: L/D = 121/36 = 3.361External shape = stepped both ends with functional groove Internal shape = no holePlane surface machining = noneAuxiliary holes and gear teeth

55、 = spur gear.Digit 1 = 2Digit 2 = 6Digit 3 = 0Digit 4 = 0Digit 5 = 6Form code in Optiz = 26006Rank Order Clustering18.11Answer: The four GT cell configurations listed in the text are (1) single machine cell, (2) group machine cell with manual handling, (3) group machine cell with semi-integrated han

56、dling, and (4) flexible manufacturing cell or flexible manufacturing system.18.12What is the key machine concept in cellular manufacturing?Answer: The key machine concept acknowledges that there is typically a certain machine in a cell that is more expensive to operate than the other machines or that performs certain critical operations. This machine is referred to as the key machine. It is important that the utilization of this key machine be high, even if it means that the other machines