1、Basics of Supply Chain Management,Session 5 Capacity Management and Production Activity Control,Session 1:Introduction to Supply Chain Management Session 2: Forecasting Session 3: Master Planning Session 4: Material Requirements Planning Session 5: Capacity Management and Production Activity Control

2、 Session 6:Inventory Fundamentals Session 7: Inventory Management Session 8:Physical Distribution Session 9:Quality Management and Purchasing Session 10:Just-in-Time Manufacturing,Course Outline,5-1a,Session 5 Objectives,Capacity management and its relation to priority planning Rated or calculated c

3、apacity Capacity required for a shop order Purpose and activities of production activity control (PAC),5-1b,Session 5 Objectives (cont.),Process of order preparation and data requirements for a PAC system Techniques of scheduling Purpose of a shop order and necessary information Implementation and c

4、ontrol of work orders Input/output reports,5-2,Capacity Management,Planning and controlling resources needed to meet production objectives Planning:Determining resources needed to meet the priority plan Selecting methods to make that capacity available Controlling:Monitoring output, comparing with t

5、he plan, and taking corrective action Capacity management occurs at each planning level,5-3,Planning Levels,5-4,Defining Capacity,The capability of a system to perform its expected function The capability of a worker, machine, work center, plant, or organization to produce output per time period,5-5

6、,Capacity Planning Process,Determine the capacity available Translate the released and planned orders into capacity required Sum up capacities required for each work center Resolve differences between available capacity and required capacity,5-6,Determining Capacity Available,Capacity available is “

7、The capability of a system or resource to produce a quantity of output in a particular time period” APICS Dictionary Available capacity can be calculated or measured To calculate available capacity, identify Available time Utilization Efficiency,5-7,Available Time,Available time:depends on the numbe

8、r of machines, number of workers, and hours of operation Number of machines (or number of workers) hours of operation What is the weekly available time for a work center that has four machines and works eight hours a day for five days a week?,5-8,Utilization,Utilization:Percentage of the time that t

9、he work center is active Example:Work center is available 120 hours a week, but actually produces goods for 90 hours,utilization,75%,100%,120,90,=,5-9,Efficiency,Efficiency:Actual output rated againststandard output Example:A work center is utilized 100 hours per week and produces 110 standard hours

10、 of work,5-10,Problem 5.1,A work center produces 90 standard hours of work in one week. The hours scheduled are 80, and 70 are actually worked. Calculate the utilization and efficiency of the work center. Utilization = Efficiency =,5-11,Rated Capacity,Rated capacity = available time x utilization x

11、efficiency Example:A work center consists of three machines and is operated eight hours a day for five days a week. Past utilization has been 75%, and efficiency has been 110%. Available time = Rated capacity =,5-12,Problem 5.2,A work center consists of six machines that are available 16 hours per d

12、ay for five days a week. Utilization is 80%, and efficiency is 110%. What is the rated weekly capacity? Rated weekly capacity =,5-13,Demonstrated Capacity,Proven capacity calculated from actual performance data Example:Over the previous four weeks, a work center produced 110, 140, 120, and 130 stand

13、ard hours of work. What is the demonstrated capacity? Demonstrated weekly capacity = standard hours/week,5-14,Load,Generated by the priority planning system (MRP) Translates the priorities, given in units, into time required at each work center in each time period Takes place at each planning level,

14、5-15,Capacity Requirements Planning,Need to Know Take Information From Open shop ordersOpen order file Planned order releasesMRP Where work is doneRouting file Time needed (standard hours)Routing file Lead timesRouting file Work center file Work center capacityWork center file,5-16,Sun.,Week,Mon.,Tu

15、es.,Wed.,Thurs.,Fri.,Sat.,Month,July,127128129130131,9101112131415,28,132133134135136,16171819202122,29,137138139140141,23242526272829,30,142143144145146,303112345,31,123124125126,2345678,27,123,July 2,2,Work Day123,Defines non-work days,Reprinted with permission, J.R. Tony Arnold, Introduction to M

16、aterials Management, Prentice-Hall.,Shop Calendar,5-17,Lead-Time Elements,QueueSetupRunWaitMove,Lead Time,QueueTime waiting before operation begins SetupTime getting ready for operation RunTime performing operation WaitTime waiting after operation ends MoveTime physically moving between operations,A

17、dapted from Material and Capacity Requirements Planning Certification Review Course, 1993, APICS,5-18,Scheduling Orders,To determine when orders should be started and completed on each work center Calculate operation time required at each work center Operation time = setup time + run time Allow for

18、queue, wait, and move times,5-19,Order quantity = 100 units From route sheet,From work center files,Schedule,Scheduling Example,5-20,Problem 5.3,5-21,Typical Load Profile,Shows the capacity required at a work center based on planned and released orders for each time period Example Work center: 10Rat

19、ed capacity: 110 standard hours/week,5-22,Resolving Differences,Change the availableUse overtime or capacity:undertime Hire or lay off Shift work force Use alternate routings Subcontract Alter the load:Alter lot sizes (May complicate schedule Reschedule for other work centers),5-23,Production Activi

20、ty Control,5-24,Objectives of PAC,Execute the MPS and MRP Optimize use of resources Minimize work in process Maintain customer service,5-25,PAC Functions,Plan Ensure resources are available Schedule start and completion dates Execute Gather relevant shop order information Release shop orders Control

21、 Establish and maintain order priority Track actual performance Monitor and control WIP, lead times, and queues Report work center performance,5-26,Reprinted with permission, J.R. Tony Arnold, Introduction to Materials Management, Prentice-Hall.,Planning, Executing, and Controlling,5-27,Manufacturin

22、g Operations,Execute Work Authorization,Control Compare Decide,Plan Schedule Replan,Production Activity Control,Data Requirements,Must KnowObtained From What and how many to produce When parts are needed What operations are needed How much time operations will take How much capacity is available at

23、each work center,5-28,Scheduling,Objectives Meet delivery dates Effectively use manufacturing resources Involves Establishing start and finish dates for each operation needed to complete an order,5-29,Scheduling and Loading Techniques,Forward scheduling:Activities are schedule from a start date with

24、 the completion date of an order computed Backward scheduling:Activities are scheduled back from the due date Infinite loading:Assumes capacity is infinite at any work center Finite loading:Assumes there is a definite limit to capacity at any work center,5-30,Reprinted with permission, BMS Associate

25、s, Inc.,Backward and Forward Scheduling,5-31,Infinite versus Finite Loading,Source: Bihun and Musolf, Capacity Management Review Course, 1985,5-32,Bottlenecks,Bottlenecks control the throughput of all products processed by them Work centers feeding bottlenecks should be scheduled at the rate the bot

26、tleneck can process A time buffer inventory should be established before the bottleneck Work centers fed by the bottleneck have their throughput controlled by the bottleneck,5-33,Execute the PlanShop Order Packet,Order number, part number, name and description, and quantity Engineering drawings Bill

27、s of material Route sheets Material issue tickets Tool requisitions Job tickets and move tickets,5-34,Period,1,2,3,4,5,Total,Planned input,38,32,36,40,44,190,Actual input,34,32,32,42,40,180,Cumulative variance,Planned output,40,40,40,40,40,200,Actual output,32,36,44,44,36,192,Cumulative variance,Pla

28、nned backlog,32,Actual backlog,32,Work center:201 Capacity per period:40 standard hours,Input/Output Control,5-35,Period,1,2,3,Total,Planned input,38,36,42,Actual input,34,36,40,Cumulative variance,Planned output,40,40,40,Actual output,42,36,42,Cumulative variance,Planned backlog,30,Actual backlog,3

29、0,Work center:20 Capacity per period:40 standard hours,Problem 5.4,5-36,Dispatch List,Work center: 10 Rated capacity: 100 standard hours per week Shop date: 250 OrderPartOrderSetupRun Operation DateNumberNumberQuantityHoursHoursStartFinish 12365541001.515249250 1217345500.53024925127525

30、0259 Total standard hours2.2120 Jobs coming:720251253 1352832 201.21.5253254,Reprinted with permission, J.R. Tony Arnold, Introduction to Materials Management,3rd ed. Prentice-Hall, 1998,5-37,Dispatching Rules,First come, first served (FCFS)Jobs performed in order received Earliest job

31、due date (EDD)Jobs performed according to due dates Earliest operation due date (ODD)Jobs performed according to operation due dates Shortest process time (SPT)Jobs sequenced according to process time Critical ratio (CR),5-38,Critical Ratio,Example: Todays date is 180 Critical Time Work OrderDue Dat

32、eRemainingRemainingRatio A185 5 days10 days .5 B19010 days10 days1.0 C19515 days10 days1.5 If CR less than ()1:Order is ahead of schedule,5-39,Production Reporting,Feedback on what is actually happening plantwide and by work center Order status Exception reports Inventory status Labor reports Machin

33、e performance,5-40,Session 5: Objectives,Discuss objectives of capacity management and its relation to priority planning Understand how to determine rated or calculated capacity (available capacity) Understand how to calculate the capacity required for a shop order (required capacity) Define the pur

34、pose of production activity control (PAC) and the activities performed Understand the process of order preparation and the data requirements for a PAC system Describe the basic techniques of scheduling Describe the purpose of a shop order and the information it should contain Summarize the process of i