Lean Systems Answer Key Part 1

Operations Management: Processes and Supply Chains Lean Systems 1) The just-in-time (JIT) philosophy is the belief that cutting inventory and removing nonvalue-added activities in operations can eliminate waste. Answer: TRUE 2) Kaizen is the Japanese term for continuous improvement. Answer: TRUE 3) In a lean system, large inventories are not considered a type of waste, because they prevent operator wait times. Answer: FALSE 4) In a lean system, wait times can be caused to some extent by long production runs. Answer: TRUE 5) Manufacturing an item before it is needed in a lean system is not considered waste, because it helps keep material flowing through the system. Answer: FALSE 6) In service systems, a common approach used to stress the system and identify problems is to reduce the number of employees doing an activity until the process begins to slow or come to a halt. Answer: TRUE 7) In manufacturing systems, one way to achieve continuous improvement can be to maintain low inventories, and periodically cut safety stocks almost to zero. Answer: TRUE 8) Just-in-time (JIT) systems need close relationships with suppliers. Answer: TRUE 9) If infrequent, large shipments of purchased items are arranged with suppliers, large inventory savings for these items can be realized. Answer: FALSE 10) JIT II refers to a form of supplier partnership that places a supplier representative, who is empowered to plan and schedule the replenishment of materials from the supplier, in the customer's plant on a full-time basis. Answer: TRUE 11) The goal of single-digit setup is to have a setup completed in fewer than 10 hours. Answer: FALSE 12) In lean systems, the need for single-digit setups is driven by the desire for small lot sizes. Answer: TRUE 13) In a lean system, excess inventory hides problems on the shop floor, and thus prevents sources of waste from being identified and eliminated. Answer: TRUE 14) While overproduction creates an item before it is needed, the extra time before an item is needed makes it easier to detect defects and reduce their impact on a process. Answer: FALSE 15) In lean systems, work-in-process inventory is a direct result of overproduction and waiting. Answer: TRUE 16) Using expensive, high precision equipment, even when simpler machines would suffice, is encouraged when lean systems are implemented, because this is the only way high quality manufacturing can be achieved. Answer: FALSE 17) Long production runs, poor material flows, and processes that are not tightly linked to one another can cause over 90% of a product's lead time to be spent waiting. Answer: TRUE 18) The push method begins the production of items in advance of customer needs. Answer: TRUE 19) Push systems are often used in firms with highly repetitive processes and well defined work flows of standardized items. Answer: FALSE 20) The pull method begins the production of an item in advance of customer needs. Answer: FALSE 21) Firms that have highly repetitive processes and well-defined work flows of standardized items often use the pull method. Answer: TRUE 22) Just-in-time (JIT) systems rely on inspectors to inspect quality into the product. Answer: FALSE 23) Quality at the source is a philosophy whereby defects are caught and corrected where they are created. Answer: TRUE 24) Automatically stopping the process when something is wrong and then fixing the problems on the line itself as they occur is called heijunka. Answer: FALSE 25) Automatically stopping the process when something is wrong and then fixing the problems on the line itself as they occur is called jidoka. Answer: TRUE 26) A power cord that can be plugged in only one way is an example of a poka-yoke. Answer: TRUE 27) The Japanese practice of andon means that production does not begin until a card or bin is empty. Answer: FALSE 28) Takt time is the cycle time needed to match the rate of production to the rate of sales. Answer: TRUE 29) Takt time is the cycle time needed to maximize utilization of an organization's workers and equipment. Answer: FALSE 30) A firm that averages sales of 320 units for every 480-minute shift it runs has a takt time of 90 seconds. Answer: TRUE 31) A firm that averages sales of 320 units for every 480-minute shift it runs has a takt time of 40 seconds. Answer: FALSE 32) Heijunka is the leveling of production load by both volume and product mix. Answer: TRUE 33) Mixed-model assembly is a type of assembly that produces a mix of models in smaller lots. Answer: TRUE 34) Productivity tends to increase when components are standardized because each worker performs a standardized task or work method more often each day. Answer: TRUE 35) A five S program includes the activities of "simplify" and "system." Answer: FALSE 36) Five S practices can enable workers to visually see everything differently, prioritize tasks, and achieve a greater degree of focus. Answer: TRUE 37) Five S practices can be applied to both manufacturing and service settings and can include offices, work spaces, tool rooms, and shop floors. Answer: TRUE 38) Preventive maintenance is typically given very low priority in just-in-time systems. Answer: FALSE 39) One tactic of Total Preventive Maintenance (TPM) is to make workers responsible for routine minor maintenance of their own equipment. Answer: TRUE 40) Lean systems are operating systems that maximize the value added of each of its activities by paring unnecessary resources and delays from them. Answer: TRUE 41) While lean systems work very well for manufacturing systems, they cannot be applied to service systems. Answer: FALSE 42) One benefit of a lean system is that it reduces space requirements. Answer: TRUE 43) Options for achieving line-flow layouts in a lean system include assigning one worker to operate several different machines in a line and creating cells to produce similar product groups called families. Answer: TRUE 44) A one-person cell in which a worker operates several different machines simultaneously to achieve a line flow is called a one-worker, multiple-machines (OWMM) cell. Answer: TRUE 45) An OWMM arrangement reduces labor requirements but increases inventory. Answer: FALSE 46) Group technology collects similar parts into families and organizes machine tools into separate cells. Answer: TRUE 47) A Kanban is a card used to control the flow of production in many just-in-time systems. Answer: TRUE 48) In a Kanban system, materials may be withdrawn without a withdrawal card if the operation requiring the material is about to run out of work. Answer: FALSE 49) Some Kanban systems are set up without Kanban cards, and use the material containers or open spaces in a work area to withdraw materials. Answer: TRUE 50) As the average processing time per container of parts increases, fewer containers are needed in a Kanban system. Answer: FALSE 51) Use of value stream mapping requires construction of a current state drawing, a future state drawing, and an implementation plan. Answer: TRUE 52) The value stream mapping tool often requires completion of the future state drawing before the current state drawing, to help managers see the future state goals and more easily identify problems with the current state of the process. Answer: FALSE 53) To complete the current state drawing of a process, a map of the current situation is developed, including such items as material and information flows, process times, setup times, batch sizes, scrap rates, and number of people required. Answer: TRUE 54) Often in value stream mapping, analysts must rely on process information from shop floor workers rather than direct observation in an effort to quickly develop a work plan and accelerate implementing the improved process. Answer: FALSE 55) The theory of constraints accepts existing system bottlenecks and works to maximize throughput given these constraints, while value stream mapping endeavors to understand how existing processes can be altered to eliminate bottlenecks and other wasteful activities. Answer: TRUE 56) A value stream map shows the flows of materials and information and the lines of responsibility and authority. Answer: FALSE 57) After the earthquake and tsunami of 2011, Toyota's suppliers and plants were able to maintain production levels due to their efficiency. Answer: FALSE 58) Toyota sets up all of its operations as experiments and teaches employees at all levels how to use the trial and error method of problem solving. Answer: FALSE 59) In the Toyota Production System, when a work station needs more material, it is obvious to both the worker and the supplier that material is needed. Further, the amount needed must be understood as well as the delivery time for replenishment. Answer: TRUE 60) The Toyota Production System requires that any process improvements are to be made at the lowest level of the organization. Answer: TRUE 61) In the Toyota Production System, services and goods flow to the next available person or machine to maintain smooth, rapid flow. Answer: FALSE 62) One big advantage of lean systems is that they can usually be put in place without any major changes to existing layouts. Answer: FALSE 63) Lean systems do not need stable master production schedules. Answer: FALSE