[Jan 20, 2024] Fully Updated CPIM Certification (CPIM-Part-2) Certification Sample Questions [Q27-Q45]

Explanation
A control chart is a tool that shows process changes and random variation over time. A control chart is a graph that plots data points over time and shows the mean and the upper and lower control limits of the process. The mean is the average value of the data, and the control limits are the boundaries of the normal variation of the process. A control chart can help monitor the stability and performance of a process by detecting any unusual or non-random patterns in the data, such as trends, cycles, or shifts. A control chart can also help identify the sources of variation in the process, whether they are common causes (inherent to the process) or special causes (external factors). A control chart can be used for both variable data (measured on a continuous scale) and attribute data (counted or categorized).
A check sheet is a tool that collects and summarizes data in a structured way. A check sheet is a simple form that records the frequency or occurrence of specific events or problems during a process. A check sheet can help organize and analyze data by showing patterns, trends, or relationships among the data. A check sheet can also help identify potential causes of problems or areas for improvement.
A histogram is a tool that displays the distribution of data in a graphical way. A histogram is a type of bar chart that shows how many times each value or range of values occurs in a data set. A histogram can help describe and compare data by showing the shape, center, spread, and variation of the distribution. A histogram can also help identify outliers, gaps, or clusters in the data.
A Pareto analysis is a tool that prioritizes problems or causes based on their frequency or impact. A Pareto analysis is based on the Pareto principle, which states that 80 percent of the effects come from 20 percent of the causes. A Pareto analysis uses a combination of a bar chart and a line graph to show the relative importance of different factors in a process. The bars represent the frequency ormagnitude of each factor, and the line represents the cumulative percentage of the total effect. A Pareto analysis can help focus on the most significant problems or causes and allocate resources accordingly.
References := Control Chart – Statistical Process Control Charts | ASQ, A Guide to Control Charts – iSixSigma, 2 Tools to Understand Variation in Your Improvement Journey, Understanding variation | Turas | Learn

Explanation
Point-of-use storage is a stock location system that places inventory close to where it is needed in the production process, reducing transportation and handling costs and improving efficiency. It is often used in repetitive manufacturing, lean environment, where the demand is stable and predictable, and the inventory is replenished frequently. Fixed location and central storage are stock location systems that store inventory in a designated area, which may require more space and movement. Floating location is a stock location system that assigns inventory to any available space, which may cause confusion and inefficiency. References: CPIM Exam Content Manual Version 7.0, Domain 5: Plan and Manage Inventory, Section 5.2: Inventory Management Methods, p. 32.

Explanation
ABC classification is an inventory categorization technique that divides items into three classes based on their usage value, which is the product of the number of units sold and the cost per unit. Class A items have the highest usage value and account for a large proportion of the total inventory value, but a small percentage of the number of items. Class B items have a moderate usage value and account for a moderate proportion of the total inventory value and the number of items. Class C items have the lowest usage value and account for a small proportion of the total inventory value, but a large percentage of the number of items1.
An advantage of applying ABC classification to a firm’s replenishment items is that it allows planners to focus on critical products. Replenishment items are items that are regularly ordered or produced to maintain a certain level of inventory. By using ABC classification, planners can prioritize the replenishment of class A items, which have the highest impact on the firm’s profitability and customer satisfaction. Planners can also apply different inventory management techniques and policies for each class of items, such as more frequent reviews, tighter controls, lower safety stocks, and higher service levels for class A items, and less frequent reviews, simpler controls, higher safetystocks, and lower service levels for class C items234. This way, ABC classification can help planners optimize the replenishment process and reduce costs, waste, and stockouts.
The other options are not advantages of applying ABC classification to a firm’s replenishment items, because they are either irrelevant or incorrect. ABC classification does not distinguish independent demand from dependent demand, which are two types of demand that depend on whether the item is sold to customers or used as a component in another item5. ABC classification does not provide better order quantities than the economic order quantity (EOQ), which is a formula that calculates the optimal order quantity that minimizes the total inventory costs6. ABC classification does not allow the firm to utilize time-phased order point (TPOP), which is a method that determines when to place an order based on the projected inventory position and the lead time7.

Explanation
Full pegging is a method of tracing the relationship between supply and demand in a manufacturing system.
Full pegging shows the link between each demand and its corresponding supply, as well as the link between each demand and the highest-level order that triggered it. Full pegging helps to identify the impact of changes in demand or supply on the production plan, and to make adjustments accordingly. Full pegging is most beneficial in an assemble-to-order (ATO) environment, where products are customized by assembling standardized components or modules according to customer specifications. In an ATO environment, full pegging can show the connection between the finished products, the components or modules, and the customer orders. This can help to optimize the inventory level, reduce lead time, and improve customer service.
Full pegging is not very useful in the other production environments. Distribute-to-order is a production strategy that delivers finished products from inventory to customers based on their orders. There is no customization or assembly involved in this strategy, so full pegging is not needed. Make-to-order is a production strategy that produces customized products from raw materials or components after receiving customer orders. There is no standardization ormodularization involved in this strategy, so full pegging is not applicable. Make-to-stock is a production strategy that produces standardized products in advance of customer demand, and stores them in inventory until they are sold. There is no customization or assembly involved in this strategy, so full pegging is not relevant. : CPIM Exam Content Manual Version 7.0, Domain 4:
Plan and Manage Supply, Section 4.1: Supply Planning Concepts, p. 23; Full Pegging; Assemble to order.

Explanation
Manufacturing lead time is the time required to acquire, manufacture, or ship goods1. It includes the time required for preprocessing, processing, and postprocessing of a finished product2. The formula for manufacturing lead time is:
Manufacturing lead time = Preprocessing time + Processing time + Postprocessing time Preprocessing time is the time needed for handling the order, making sales order, and preparing supplies2.
Processing time is the period when the product is manufactured or collected. Postprocessing time is the time of delivery2.
In this question, we are given the following information:
The product is Item A, which requires Operations 10, 20, and 30 in a work cell The order quantity is 10 units The operations require no set up time The processing times for each operation are:

To find the shortest manufacturing lead time, we need to assume that the preprocessing and postprocessing times are zero, and that the operations can be performed in parallel. This means that the work cell can process
10 units of Item A simultaneously, without any waiting or transportation time.
Therefore, the shortest manufacturing lead time is equal to the longest processing time among the three operations. Since Operation 10 has the longest processing time of 1 hour per unit, the shortest manufacturing lead time is:
Manufacturing lead time = 1 hour x 10 units = 10 hours
However, this answer is not among the options given. Therefore, we need to consider another possibility: that the work cell can only process one unit of Item A at a time, and that the operations must be performed in sequence. This means that each unit of Item A must complete Operation 10 before moving to Operation 20, and then to Operation 30. In this case, the shortest manufacturing lead time is equal to the sum of the processing times for all three operations multiplied by the order quantity. Therefore, the shortest manufacturing lead time is:
Manufacturing lead time = (1 hour + 0.5 hour + 0.5 hour) x 10 units = 20 hours However, this answer is also not among the options given. Therefore, we need to consider one more possibility: that the work cell can process one unit of Item A at a time, but that the operations can be performed in parallel with overlapping times. This means that as soon as one unit of Item A finishes Operation
10, it moves to Operation 20, while another unit of Item A starts Operation 10. Similarly, as soon as one unit of Item A finishes Operation 20, it moves to Operation 30, while another unit of Item A starts Operation 20. In this case, the shortest manufacturing lead time is equal to the sum of the processing times for all three operations plus the processing times for each operation multiplied by the order quantity minus one. Therefore, the shortest manufacturing lead time is:
Manufacturing lead time = (1 hour + 0.5 hour + 0.5 hour) + (1 hour + 0.5 hour + 0.5 hour) x (10 units – 1) = 12 hours This answer is among the options given and it is the shortest possible manufacturing lead time under these assumptions. Therefore, the correct answer is B. 12 hours.
References : Manufacturing Lead Time; How to Calculate and Reduce Lead Time; How To Calculate Lead Time?; What Is Lead Time? How to Calculate Lead Time in Different Industries.

Explanation
Input/output control (I/O) is a type of tool that is used for monitoring a capacity plan. A capacity plan is a statement of the resources needed to meet the production plan over a medium-term horizon. A capacity plan can be stated in different units of measure depending on the type of manufacturing environment, such as hours, units, tons, or dollars. Input/output control (I/O) is a method of measuring and comparing the actual input and output of a work center or a production line against the planned input and output. Input is the amount of work that is released to the work center or the production line, and output is the amount of work that is completed by the work center or the production line. Input/output control (I/O) helps to monitor the performance and efficiency of the work center or the production line, and to identify any deviations or problems that may affect the capacity plan. Input/output control (I/O) also helps to adjust the input or output levels as necessary to maintain the balance between demand and supply, and to achieve the desired throughput.
References: CPIM Exam Content Manual Version 7.0, Domain 6: Plan, Manage, and Execute Detailed Schedules, Section 6.3: Monitor Detailed Schedules, Subsection 6.3.2: Describe how to monitor input/output control (I/O) (page 60).

Explanation
A part that is sold as a service part and also used as a component in another part is called a dual-sourced item.
A dual-sourced item has two sources of demand: the external demand from the customers who buy the service part, and the internal demand from the parent part that uses the component. The planning for a dual-sourced item should include both sources of demand in the gross requirements, so that the net requirements can be calculated correctly. The service part demand can be included in the gross requirements by using a planning bill of material, which is a special bill of material that shows the relationship between a parent item and its service parts. A planning bill of material allows the system to explode the service part demand to the component level and generate planned orders for both the service part and the component.
The other statements about the planning for this part are false. Its low-level code is not zero, because it is not an independent item. It has a higher low-level code than its parent item, because it is a component of another item. The material requirements for the part will not be understated, if both sources of demand are included in the gross requirements. It should have some safety stock, to protect against demand and supply uncertainties. References: CPIM Part 2 Exam Content Manual, Domain 4: Plan and Manage Supply, Section
4.2: Material Requirements Planning (MRP), p. 22-23.

Explanation
The inventory turns ratio is a financial metric that measures how efficiently a company manages its inventory.
The inventory turns ratio is calculated by dividing the cost of goods sold (COGS) by the average inventory investment. The cost of goods sold is the direct cost of producing or purchasing the goods sold by the company. The average inventory investment is the average value of the inventory held by the company over a period of time. A higher inventory turns ratio indicates a higher inventory turnover and a lower inventory holding cost.
In this case, the company sold 8,400 units last year, and the unit cost is $207. Therefore, the cost of goods sold is:
COGS = Unit cost x Units sold = 207 x 8,400 = $1,738,800
The average inventory investment was $42,000. Therefore, the inventory turns ratio is:
Inventory turns ratio = COGS / Average inventory investment = 1,738,800 / 42,000 = 41.4 To express the inventory turns ratio as a whole number, we can round it to the nearest integer. Therefore, the inventory turns ratio is 5.
References: CPIM Exam Content Manual Version 7.0, Domain 5: Plan and Manage Inventory, Section 5.1:
Develop Inventory Plans, Subsection 5.1.2: Describe how to develop an inventory policy (page 44).

Explanation
A 5S environment is a type of workplace organization method that uses a list of five Japanese words: seiri (sort), seiton (set in order), seiso (shine), seiketsu (standardize), and shitsuke (sustain). The goal of 5S is to create a clean, uncluttered, safe, and well organized workplace that helps reduce waste and optimize productivity. A 5S environment should be maintained for the following reason:
To support standard work: Standard work is a set of documented procedures that define the best way to perform a task or process. Standard work helps to ensure quality, efficiency, safety, and consistency. A
5S environment supports standard work by providing a clear and visible layout of the work area, tools, materials, and instructions. A 5S environment also helps to maintain the condition and performance of the equipment and facilities. A 5S environment enables workers to follow standard work easily and effectively.
References: 5S – What are The Five S’s of Lean? | ASQ; 5S (methodology) – Wikipedia.

Explanation
A capacity-leading strategy is a proactive approach that adds or subtracts capacity in anticipation of future market demand. It is an aggressive strategy with the objective of improving the service level and decreasing lead time1. An advantage of adopting a capacity-leading strategy is that there issufficient capacity to meet demand, which means that the organization can satisfy customer needs and expectations, as well as capture new market opportunities. A capacity-leading strategy can also help the organization gain a competitive edge by being the first to offer new products or services, or by lowering prices due to economies of scale2.
The other options are not advantages of adopting a capacity-leading strategy. There is not necessarily sufficient demand to consume capacity, which means that the organization may face overcapacity problems, such as high inventory costs, low utilization rates, and reduced profitability3. All demand is not satisfied, and profit is not maximized, because there may be other factors that affect customer satisfaction and profitability, such as quality, price, or service4. Overcapacity problems are not minimized, but rather increased, by adopting a capacity-leading strategy, because the organization may have more capacity than needed if demand does not increase as expected3.
References: CPIM Part 2 Exam Content Manual, Domain 4: Plan and Manage Supply, Section 4.1: Supply Management Concepts and Tools, p. 33-34; Capacity Planning Strategies: Types, Examples, Pros And Cons – Toggl; Lead Capacity Strategy, Lead Demand Strategy – UniversalTeacher.com; Capacity Planning Strategies For End-to-End Supply Chain Profitability; Capacity Planning Strategies: Types, Examples, Pros And Cons – Toggl.

Explanation
A production cell is a group of machines or workstations that are arranged in a layout that facilitates the flow of materials and work-in-progress in a manufacturing system. A production cell is usually designed to produce a family of products or services that have similar characteristics or requirements. A production cell is often based on the principles of lean manufacturing and group technology, which aim to eliminate waste and improve quality. When designing a production cell, the most important consideration is the flow of materials into the cell and sequencing of operations to minimize total cycle time. The flow of materials into the cell refers to the movement and direction of the raw materials, components, or modules that enter the cell for processing. The sequencing of operations refers to the order and arrangement of the machines or workstations that perform the processing steps within the cell. Minimizing total cycle time refers to reducing the time it takes to complete a product or service from start to finish. By considering these factors, a production cell can achieve high efficiency, flexibility, and productivity.
The other options are not the most important considerations when designing a production cell. The unit per hour requirement for the production cell to meet the sales forecast is not the most important consideration, as it is a result of the demand planning and capacity planning functions, which are separate from the production cell design. The unit per hour requirement indicates how many units of a product or service the production cell needs to produce in an hour to meet the expected customer demand. The output rate for the first operation and move time after the last workstation are not the most important considerations, as they are only parts of the total cycle time calculation, which also includes the processing time and waiting time for each operation. The output rate for the first operation is the number of units that the first machine or workstation in the cell can produce in an hour. The move time after the last workstation is the time it takes to transport the finished product or service from the last machine or workstation in the cell to the next stage or destination. The take time requirement for each operator to meet the monthly production goals of the plant is not the most important consideration, as it is a measure of labor productivity, which is affected by factors such as skill, training, motivation, and supervision. The take time requirement for each operator is the amount of time that an operator needs to complete one unit of a product or service. References: CPIM Exam Content Manual Version
7.0, Domain 6: Plan, Manage, and Execute Detailed Schedules, Section 6.2: Detailed Scheduling Methods, p.
38; Cellular manufacturing; Production Cell.

Explanation
The question is about forecasting the demand for a product, and the options are different levels of aggregation or disaggregation. The highest percentage of error will occur at the most disaggregated level, which is the field warehouses. The field warehouses are the locations where the finished products are stored and delivered to the customers. The demand at the field warehouses is affected by various factors, such as customer preferences, seasonality, promotions, and competition. The demand at the field warehouses is also more volatile and uncertain than the demand at the higher levels of aggregation, such as the market segment or the central warehouse. Therefore, forecasting the demand at the field warehouses will have the highest percentage of error, which means that the forecast will deviate more from the actual demand.
The other options are not the levels where the highest percentage of error will occur. The master schedule is not a level of aggregation or disaggregation, but a plan that specifies the quantity and timing of finished products to be produced in a given period. The master schedule is based on the forecasted demand, the customer orders, and the production capacity. The master schedule does not have a percentage of error, but it may have a variance or deviation from the actual production output. The market segment is a level of aggregation that groups the customers or products based on their common characteristics or needs. The market segment is a higher level than the field warehouses, and it has less variability and uncertainty in demand.
Therefore, forecasting the demand at the market segment will have a lower percentage of error than forecasting at the field warehouses. The central warehouse is a level of aggregation that consolidates the inventory from different sources and distributes it to different destinations. The central warehouse is a higher level than the field warehouses, and it has less variability and uncertainty in demand. Therefore, forecasting the demand at the central warehouse will have a lower percentage of error than forecasting at the field warehouses.

Explanation
The most appropriate action by the master scheduler is to forward the request to senior management.
According to the Time Fence Control (MRP and Supply Chain Planning Help) – Oracle, the demand time fence is a period within which the planning process does not consider forecast demand when calculating actual demand, and the planning time fence is a period within which the planning process does not alter the current material plan or master schedule. The master scheduler can make changes to the master schedule within the planning time fence, but only with approval from senior management. The request from marketing falls between the demand and the planning time fences, which means that it may affect the current material plan or master schedule, as well as the capacity and resource requirements of the production system. Therefore, the master scheduler should forward the request to senior management, who can evaluate the impact and feasibility of the request, and decide whether to approve or reject it.

Explanation
Sales and operations planning (S&OP) in a make-to-stock (MTS) environment is concerned with projecting inventory. S&OP is an integrated planning process that aligns demand, supply, and financial planning and is managed as part of a company’s master planning1. MTS is a traditional production strategy that is used by businesses to match inventory with anticipated consumer demand2. Inventory is the quantity and value of materials and products that are available in stock or in transit3.
S&OP in an MTS environment is concerned with projecting inventory because inventory is the key link between demand and supply. Inventory can be classified into three types: raw materials, work-in-process, and finished goods3. S&OP aims to balance the inventory levels of these types with the expected demand and supply plans, as well as the financial objectives of the company. S&OP can help optimize inventory management by:
Reducing inventory costs, such as holding, ordering, and shortage costs3.
Improving inventory turnover, which is the ratio of sales to average inventory3.
Increasing inventory availability, which is the percentage of orders that can be fulfilled from stock3.
Enhancing inventory quality, which is the degree of conformance to specifications and standards3.
The other options are not as relevant for S&OP in an MTS environment as inventory. Item forecasts are estimates of future demand for specific products or services based on historical data, market trends, or customer inputs4. Item forecasts are an input to S&OP, not an output. S&OP uses item forecasts to generate aggregate demand plans for product families or categories, which are then matched with aggregate supply plans for production capacity or resources1. Backlog is the quantity of customer orders that have been received but not yet fulfilled3. Backlog is not applicable for S&OP in an MTS environment, because MTS products are produced before customer orders are received. MTS products are delivered from stock, not from backlog. Bookings are the quantity of customer orders that have been received and confirmed3. Bookings are also not applicable for S&OP in an MTS environment, because MTS products are not dependent on customer orders. MTS products are based on forecasted demand, not actual demand.
References: Make To Stock (MTS): Definition, Example, and How It Works – Investopedia; Forecasting – Definition & Examples – ASQ; What is Sales and Operations Planning (S&OP) | Oracle; Inventory Management – Definition, Types, Objectives and Examples.

Explanation
Finished goods inventory is a type of inventory that consists of the final products that are ready for sale to the customers. Finished goods inventory investment is the value of the finished goods inventory held by the company. Service level is a measure of customer satisfaction that indicates the percentage of customer orders that can be fulfilled from the available inventory. Service level typically will increase when finished goods inventory investment is increased, because more inventory means more ability to meet the customer demand.
However, the relationship between service level and finished goods inventory investment is not linear, but rather asymptotic. This means that service level will increase at a decreasing rate as finished goods inventory investment increases. In other words, the marginal benefit of increasing finished goods inventory investment will diminish as the service level approaches 100%. This is because there is a limit to how much inventory can improve the service level, and beyond a certain point, the additional inventory will not have a significant impact on customer satisfaction.
References: CPIM Exam Content Manual Version 7.0, Domain 5: Plan and Manage Inventory, Section 5.1:
Develop Inventory Plans, Subsection 5.1.2: Describe how to develop an inventory policy (page 44).

Explanation
Nervousness is a term that describes the instability or variability of a production schedule due to frequent changes in demand, supply, or capacity. Nervousness can cause disruption, inefficiency, and waste in the production system, as well as lower customer service and satisfaction. Changing the due dates of open orders is a main cause of nervousness in the schedule, as it affects the priority and sequence of the production orders, and may require rescheduling or replanning of the resources and activities. Changing the due dates of open orders may be necessary to accommodate urgent or unexpected customer requests, but it also increases the complexity and uncertainty of the production process.
The other options are not the main negative effects of changing the due dates of open orders. The schedule information becomes inaccurate is not a negative effect, but a consequence of changing the due dates of open orders. The schedule information reflects the planned input/output of the production system, and it needs to be updated and communicated whenever there are changes in the due dates of open orders. The customer service level decreases is not a negative effect, but a possible outcome of changing the due dates of open orders. The customer service level measures the degree to which the production system meets or exceeds the customer expectations in terms of quality, quantity, and delivery. Changing the due dates of open orders may improve the customer service level for some customers, but it may also deteriorate it for others, depending on how the changes affect their orders. The schedule does not support demand is not a negative effect, but a potential problem of changing the due dates of open orders. The schedule should support demand by ensuring that the production system can produce or deliver what the customers want, when they want it. Changing the due dates of open orders may create a mismatch between the schedule and demand, which may result in overproduction or underproduction, stockouts or excess inventory, or late or early deliveries. References: CPIM Exam Content Manual Version 7.0, Domain 6: Plan, Manage, and Execute Detailed Schedules, Section 6.1: Detailed Scheduling Concepts, p. 36; Nervousness; Production Schedule.

Explanation
The most appropriate production output reporting method for repetitive manufacturing is backflush. Repetitive manufacturing is a production system where the same or similar products are produced in large quantities or in a continuous flow1. Backflush is a method of reporting output and consumption of materials at the end of the production process, rather than at each operation or stage2. Backflush can simplify and streamline the production output reporting process, as it eliminates the need for tracking and recording each individual transaction or movement of materials and components. Backflush can also reduce the paperwork, errors, and costs associated with production output reporting2.
The other options are not as appropriate as backflush for repetitive manufacturing. Operation-by-operation is a method of reporting output and consumption of materials at each operation or stage of the production process3. This method can provide more detailed and accurate information about the production performance and costs, but it can also be more complex and time-consuming, as itrequires tracking and recording each individual transaction or movement of materials and components. Count point is a method of reporting output and consumption of materials at selected points or milestones in the production process4. This method can provide a balance between detail and simplicity, but it can also introduce errors or discrepancies, as it requires estimating or extrapolating the output and consumption of materials between the count points. Job tickets are documents that record the time, materials, and costs associated with a specific job or order5. This method can provide more flexibility and customization, but it can also be more suitable for job shop or batch production systems, where different products are produced in small quantities or on demand.
References : Repetitive Manufacturing: Definition & Benefits; Backflush Costing: Definition & Example; Operation by Operation Reporting – ERP Software Blog; Count Point Reporting – ERP Software Blog; Job Ticket Definition.

Explanation
An effective single-sourcing relationship requires that the organizations must be mutually dependent. This means that both the customer and the supplier rely on each other for their success and benefit from the partnership. Mutual dependence can foster trust, collaboration, communication, innovation, and problem-solving between the parties. It can also reduce the risks of supply disruptions, quality issues, price fluctuations, and contract breaches. Mutual dependence can be achieved by aligning the goals, values, and strategies of the organizations, as well as by sharing information, resources, and risks. Demand for the customer’s products does not have to be stable for a single-sourcing relationship to work. In fact, single sourcing can help the customer cope with demand variability by ensuring a consistent supply of goods or services from the supplier. The supplier does not have to offer the lowest price per unit for a single-sourcing relationship to be effective. The customer may choose a single supplier based on other factors, such as quality, delivery, innovation, or reputation. The price per unit may not reflect the total cost of ownership, which includes other costs such as transportation, inventory, maintenance, and warranty. The organizations do not have to be located close to each other for a single-sourcing relationship to be successful. With advances in technology and logistics, distance is not a major barrier for communication and coordination between the customer and the supplier. Moreover, single sourcing can reduce the complexity of managing multiple suppliers across different locations. References := What Is Single Sourcing? (Plus Benefits and 7 Examples), Single Sourcing Vs Sole Sourcing Sourcing | CIPS, What Is Single Sourcing In Procurement And Why Is It Important?

Explanation
Safety capacity in lean environments is where take time is greater than cycle time. Take time is the average time between the start of production of one unit and the start of production of the next unit1. Cycle time is the average time it takes to complete one unit of a product or service2. Safety capacity is the amount of capacity that is reserved to deal with unexpected events or fluctuations in demand or supply3.
In lean environments, the goal is to minimize waste and maximize value by producing only what the customer wants, when the customer wants it, and in the exact amount4. This means that the production system should be synchronized with the customer demand, and the take time should match the cycle time. However, in reality, there may be variations or uncertainties in the demand or supply, such as changes in customer preferences, seasonal patterns, quality issues, equipment breakdowns, or supplier delays. These variations or uncertainties can cause disruptions or imbalances in the production system, leading to stockouts, overproduction, waiting, defects, or rework5.
To cope with these variations or uncertainties, lean environments may use safety capacity as a buffer or contingency plan. Safety capacity is where take time is greater than cycle time, meaning that the production system has some extra capacity to produce more than what the customer currently demands. This extra capacity can be used to absorb the variations or uncertainties and maintain a smooth and stable production flow6. However, safety capacity should not be confused with excess capacity, which is where take time is much greater than cycle time, meaning that the production system has a lot of idle or underutilized resources. Excess capacity is a waste that should be eliminated or reduced in lean environments7.
Therefore, safety capacity in lean environments is where take time is greater than cycle time.
References: 1: Take Time Definition 1 2: Cycle Time Definition 2 3: Safety Capacity Definition 3 4: Lean Manufacturing Definition 4 5: The Seven Wastes of Lean 5 6: Capacity Planning Tools 6 7: Excess Capacity