Exam 5: Constraint Management

Lanny discovers that the bottleneck is the riveting machine so he schedules all production around when that machine is available.This is an example of elevating the constraint in the five-step constraint management process.

The first step in applying the Theory of Constraints is to identify the constraint.

Table 5.2 A company makes four products that have the following characteristics: Product A sells for $75 but needs $20 of materials and $20 of labor to produce;Product B sells for $90 but needs $45 of materials and $20 of labor to produce;Product C sells for $110 but needs $50 of materials and $30 of labor to produce;Product D sells for $135 but needs $75 of materials and $40 of labor to produce.The processing requirements for each product on each of the four machines are shown in the table. Work centers W,X,Y,and Z are available for 40 hours per week and have no setup time when switching between products.Market demand is 50 As,60 Bs,70 Cs,and 80 Ds per week.In the questions that follow,the traditional method refers to maximizing the contribution margin per unit for each product,and the bottleneck method refers to maximizing the contribution margin per minute at the bottleneck for each product. -Use the information in Table 5.2.Using the traditional method,which product should be scheduled first?

You have been assigned a line balancing task and given a list of tasks,their precedence requirements,and the time needed to accomplish them.As you begin to balance the line,you realize that you must make some assumptions.What are these assumptions and which of them has the greatest impact on the success of your balance?

Table 5.3 King Supply makes four different types of plumbing fixtures: W,X,Y and Z.The contribution margins for these products are: $70 for Product W,$60 for Product X,$90 for Product Y and $100 for Product Z.Fixed overhead is estimated at $5,500 per week.The manufacture of each fixture requires four machines,Machines #1,2,3 and 4.Each of the machines is available for 40 hours a week and there is no setup time required when shifting from the production of one product to any other.The processing requirements to make one unit of each product are shown in the table.Weekly product demand for the next planning period has been forecasted as follows: 70 Ws,60 Xs,50 Ys and 30 Zs. In the questions that follow,the traditional method refers to maximizing the contribution margin per unit for each product,and the bottleneck method refers to maximizing the contribution margin per minute at the bottleneck for each product. -Use the information in Table 5.3.Using the traditional method,in what sequence should the fixtures be scheduled for production?

A competent operations manager should first eliminate all of the bottlenecks from the process.

Table 5.1 A company makes four products that have the following characteristics: Product A sells for $50 but needs $10 of materials and $15 of labor to produce;Product B sells for $75 but needs $30 of materials and $15 of labor to produce;Product C sells for $100 but needs $50 of materials and $30 of labor to produce;Product D sells for $150 but needs $75 of materials and $40 of labor to produce.The processing requirements for each product on each of the four machines are shown in the table. Work centers W,X,Y,and Z are available for 40 hours per week and have no setup time when switching between products.Market demand for each product is 80 units per week.In the questions that follow,the traditional method refers to maximizing the contribution margin per unit for each product,and the bottleneck method refers to maximizing the contribution margin per minute at the bottleneck for each product. -Use the information in Table 5.1.Using the traditional method,what is the optimal product mix (consider variable costs only-overhead is not included in this profit calculation)?

Which statement about transfer batch sizes is BEST?

________ is the total time taken from the start to the finish of a process.

Table 5.4 The Superior Management Company assembles muffalettas in The Big Easy.The steps to making a world class sandwich and the time required (in seconds)for each step are shown in the table. -Customers demand muffalettas at the rate of 20 sandwiches per hour.Use the information in Table 5.4 to determine which tasks are assigned to station 3 in the most efficient balance that meets the desired output rate exactly.

Figure 5.1 The figure above shows the process for paying tuition at a major university.Students receive their bill,for the next term,for review.They are directed to different tables for clarifications,before being asked to pay their tuition at E.The numbers in parentheses are the time in minutes for each step of the process. -Use the information in Figure 5.1.What is the throughput time for the A-B-C-E process route?

The key to preserving bottleneck capacity is to watch them carefully and keep them as busy as practical

Balance the assembly line for the tasks contained in the table.The desired output is 240 units per day.Available production time per day is 480 minutes.What is the efficiency for the balanced assembly line?

Figure 5.4 -Use the information in Figure 5.4.If each task has a work time of one minute and there are 480 work minutes in a day,what is the task assignment at the fourth workstation if maximum output is desired?

Table 5.5 Balance the following line for an output rate of 3 units per minute. -Use the information in Table 5.5.What is the balance delay for your solution?

What is contribution margin for a product? How might it be used to manage the productive resources on a shop floor?

Use the process flow diagram to determine which of these events has the greatest net benefit.

Balance the line in order to achieve maximum output for this eight-activity product.Then balance the line to maximize the efficiency of the operation.How do the levels of output (assume an eight hour day)and line efficiencies compare?

Table 5.3 King Supply makes four different types of plumbing fixtures: W,X,Y and Z.The contribution margins for these products are: $70 for Product W,$60 for Product X,$90 for Product Y and $100 for Product Z.Fixed overhead is estimated at $5,500 per week.The manufacture of each fixture requires four machines,Machines #1,2,3 and 4.Each of the machines is available for 40 hours a week and there is no setup time required when shifting from the production of one product to any other.The processing requirements to make one unit of each product are shown in the table.Weekly product demand for the next planning period has been forecasted as follows: 70 Ws,60 Xs,50 Ys and 30 Zs. In the questions that follow,the traditional method refers to maximizing the contribution margin per unit for each product,and the bottleneck method refers to maximizing the contribution margin per minute at the bottleneck for each product. -Use the information in Table 5.3.Using the bottleneck method,what is the optimal product mix?

Constraints at any step causes imbalance in the capacity of a process.As a result,the overall performance of a system is affected which in turn leads to low customer satisfaction and loss of money even with high sales level.