Push And Pull Production Systems

Chapter 8. Push and pull production systems MULTIPLE CHOICE 1. In general, there are five questions regarding manufacturing and control. Which of the following correctly connects the question with solutions? a. Which unit of production should be made next? (scheduling and sequencing Techniques) b. How should the units of production be built? (lot sizing techniques, replenishment systems) c. Where should the units of production be made? (high-quality and on-time documentation) d. When should the next unit of production be made? (dispatching rules) ANS: A 2. Which of the following statements do not correctly describe push manufacturing? (1). The serial operations are independently optimized (2). Compared to pull, push manufacturing is a relatively new concept (3). Forecasts of demands is a significant factor in deciding on material flow (4). It focuses on maximizing inventory investment a. (1) c. (2) b. (2) and (4) d. (1) and (3) ANS: C 3. Which of the following statements are the disadvantages of the push system? (1). Increases the work load at the management level (2). Performance is dependent of forecasting ability (3). Increases work-in-process inventory (4). Require less managerial resources at a shop floor level a. (1) c. (1), (2), and (3) b. (2) and (4) d. (3) and (4) ANS: C 4. Which of the following descriptions are not correct for a push system? (1). There is no clear visibility between processes (2). The workers on shop floor lack the autonomy to stop the manufacturing on their own initiative (3). Production is only initiated when the down- stream process initiates its own activity (4). The WIP inventory levels are high at most locations a. (2) and (4) c. (1) and (3) b. (4) d. (3) ANS: D 5. With a push system, it is more likely that defects will pass through to the next process without being detected. Choose among the following, the likely consequences of this situation. (1). Increase in rework costs (2). Increase in customer returns (3). Increase in asset utilization (4). Increase in overall throughput a. (1) c. (1), (3), and (4) b. (1) and (2) d. (2) and (3) ANS: B 6. Which of the following statements do not correctly describe pull manufacturing? (1). Material flow is determined by the need of the downstream workstation (2). Control is transferred from the beginning of the line to the end (3). A single piece flow is ideal for a push system and not for a pull system (4). Tries to minimize the number of items pulled at the same time a. (2) and (4) c. (1) and (3) b. (4) d. (3) ANS: D 7. Among the following relative advantage claims for a pull manufacturing, which ones are likely to be true? (1). The system operates with almost no WIP inventory (2). Less maintenance is required (3). There is not much need to forecast demands (4). Only when it is needed, value is added to incomplete product a. (4) c. (2) and (3) b. (1) and (4) d. (1), (3), and (4) ANS: A 8. Among the following relative disadvantage claims for a pull manufacturing, which one is most likely to be true? a. The machine utilization will increase b. People may be idle at times c. Asset utilization may increase d. The worker turnover is higher than push manufacturing ANS: B 9. Depending on who you ask, you will get different answers regarding how to distinguish a pull system from a push system depending. Choose the likely bases for distinguishing a pull system from a push system depending. (1). Information flow (2). Order release (3). Shop floor WIP levels (4). Lot size a. (1) c. (1), (2) and (3) b. (2) and (4) d. (4) ANS: C 10. Which of the following statements regarding the manufacturing systems are correct? (1). For a MRP system, customer demand forecast is essential for material control (2). For a pull system, larger lot sizes and shorter lead times are required (3). For a pull system, a JIT philosophy needs to be solidified within the organization (4). For a Kanban system, each work station need to respond independently from other work stations a. (1) c. (1), (3) and (4) b. (1) and (3) d. (4) ANS: B 11. Which of the following dual-card Kanban rules are not correct? (1). One Kanban per container (2). The more Kanban cards are in the system, the more smoothly manufacturing operates (3). Standardized Containers and loads (4). In some cases, parts can be made without a production Kanban a. (4) c. (1), (3) and (4) b. (2) and (4) d. None of the above ANS: B 12. A company implemented a computerized Kanban system that required a considerable amount of asset investment. However, the performance enhancement was not as much as expected. Which of the following correctly explains the reason for this phenomenon? a. The advantage of the Kanban system is its simplicity and physicality and not the concept itself b. The computer system was not properly set up according to the characteristics of the process being controlled c. There was to many virtual Kanban cards in the system d. The manufacturing environment was not suited to a Kanban system ANS: A 13. Choose, among the following statements, the ones which correctly describe the inner workings of a basic Kanban production system. (1). A Kanban card is attached to every 10th container of items that has been produced (2). A Kanban card is an easily understood, virtual signal (3). Kanban is the Japanese word for container (4). The Kanban card stays with the container until the contents are used once attached a. (2) c. (1) and (4) b. (2) and (3) d. (4) ANS: D 14. The dual Kanban system uses more than one type of Kanban cards. Choose the correct type of Kanban cards for a dual Kanban system (1). Withdrawal Kanban (2). Inventory Kanban (3). Supermarket deposit Kanban (4). Transportation Kanban a. (1) c. (3) and (4) b. (1) and (2) d. (2) ANS: A 15. For US. Inc., there have been having problems with deciding on the number of Kanban cards in the system. There were several material shortages during the last period. In order to prevent shortages while maintaining an efficient Kanban system, how many Kanban cards should be released in the system? The lead time is 1 day and the safety stock level is set to 10% of the average demand during the day. The container size is 15 units per container. The following is the demands over the last 10 days: Days Daily demands 1 2 3 4 5 6 7 8 9 10 100 98 97 120 123 125 121 100 110 105 a. 8 cards c. 5 cards b. 12 cards d. 15 cards ANS: A 16. For Panama. Inc., there have been having problems with deciding on the number of Kanban cards in the system. There were several material shortages during the last period. In order to prevent shortages while maintaining an efficient Kanban system, how many Kanban cards should be released in the system? The lead time is 2 day and the safety stock level is set to 15% of the average demand during the day. The container size is 10 units per container. The following is the demands over the last 10 days. Days 1 2 3 4 5 6 7 8 9 10 Daily demands 100 98 97 120 123 125 121 100 110 105 a. 10 cards c. 30 cards b. 5 cards d. 25 cards ANS: D 17. John is tasked with purchasing some new containers to use in the company's Kanban system. While he has most of the Kanban system configuration information, he cannot find the container size information. Find the container size using the Kanban system configuration information. The average demand during lead time is 1025 units and the safety stock level is set to 19 units. There are currently 8 Kanban cards in the system. Find the closet size. a. 50 units c. 25 units b. 130 units d. 70 units ANS: B 18. Susan is tasked with purchasing some new containers to use in the company's Kanban system. While she has most of the Kanban system configuration information, she cannot find the container size information. Find the container size using the Kanban system configuration information. The average daily demand is 2050 units and lead time is 3 days. The safety stock level is set to 200 units. There are currently 10 Kanban cards in the system. Find the closest size. a. 150 units c. 565 units b. 330 units d. 635 units ANS: D 19. Choose the correct statement regarding a Kanban system. a. Kanban system increases the buffer inventory levels b. Maximizing the number of Kanbans available will reveal problems that need to be resolved c. The upper bound on the work in process inventory (WIP) is set by the number Kanban Cards d. The Kanban system is impractical in real life manufacturing environments ANS: C 20. Mom &Pop Inc. uses 6 kanban cards for a system with a container size of 500 units. Using the demand information bellow, find the safety stock level. The estimated lead time is 1 day. Daily 1 Demand 1,000 2 500 3 3,000 a. 1,000 units c. 250 units b. 1,200 units d. 800 units 4 4,000 ANS: A SHORT ANSWER 1. Describe the difference between a push and pull system in on paragraph. 5 3,000 6 500 ANS: Read about pull 2. Explain in your own words, the reason why a push system would increase the WIP inventory levels relative to a pull system. ANS: Read about pull 3. Describe the concept of a pull system in one sentence. ANS: Read about pull 4. In your own words, briefly describe the objectives of a Pull Production Planning System. ANS: Read about pull 5. List the 3 ways to distinguish a pull system from a push system. ANS: Read about pull 6. Explain what the following sentence means. "Control is transferred from the beginning of the line to the end with the pull system." ANS: Read about pull 7. The push system measures the performance of each work station separately based on measures such as machine utilization. If all the work stations are operating at the peak of their current possible machine utilization, is this enough to say that this push manufacturing process is at an optimal state? Is there areas that could go wrong? ANS: basic underlining understanding of push manufacturing 8. Describe in one paragraph, what a Hybrid production System is. ANS: Read about Hybrid production System 9. How is the Kanban system similar to fixed-order inventory systems? ANS: Read about lean and Kanban system 10. Misa is tasked with purchasing some new containers to use in the company's kanban system. While she has most of the kanban system configuration information, she cannot find the container size information. Find the container size using the kanban system configuration information. The average daily demand is 550 units and lead time is 2 days. The safety stock level is set to 30 units. There are currently 6 kanban cards in the system. Find the closest size. ANS: 188 unit size container