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產能管理(Capacity Management)

Ahua.liao

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Outline

• 生產環境演變與相關管理工具之關係• 製造環境分類• 製造規劃及控制系統架構• 產能管理相關概念• 粗估產能規劃 (RCCP)• 產能需求規劃 (CRP)• 投入 / 產出規劃及控制 (I/O Planning & Control)• 作業排程 (Operation Sequencing)• 結論

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Competitive Priority

• 1950~1960– Cost

• 1970~1980– Quality

• 1990~2000– Delivery、 Flexibility、 Service – Global-wise

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Competitive Priority

手工藝時代

大量生產

豐田生產系統

及時生產系統

零庫存生產系統

世界級製造

成本

品質彈性

交期

1920 1950 1960 1970 1980 1990 2000

服務、創新、全球化

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Planning Evolution

MRP MRP II ERP

1970 1980 1990 2000

APS

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MRP-1960’s and 70’s

• Material Requirements Planning

• Master Production Scheduling

• Unconstrained

Demand Supply

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MRP II-1980’s

• Unconstrained

• Manufacturing Planning and Control, with

manual processes to “close the loop”

• Capacity Management

• Financial Integration

8

ERP- 1990’s

• An accounting-oriented information

system for identifying and planning the

enterprise-wide resources needed to

take, make, ship, and account for

customer orders. [APICS dictionary]

9

The Vision The DeliveryMRP

MRP II

ERP

Extended ERP

Reduced inventory through “infinite” manufacturing planning

Reduced inventory, fewer stock-outs and accurate financial records through “infinite” manufacturing planning and periodic transaction processing.

Customer focused, dynamically balanced enterprise through asset optimization and real-time transaction processing.

Customer focused, dynamically balanced value network through asset optimizationand real-time transaction processing.

MRP

MRP II

MRP II (plus)

Supply Chain

The vision of ERP is Evolving to include the Extended Enterprise

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資訊系統之演進• MRP I -- 1960~1980

– 生產者導向大量生產– 產品以價格及功能取勝生產成本降低– 整合： MPS 及 BOM

• MRP II -- 1980~1990– 消費者導向少樣多量生產– 產品以多樣化及高品質取勝生產彈性及消除浪廢– 整合：製造、行銷、財務、人事、專案

• ERP/SCM -- 1990~– 消費者導向大量客製化– 快速反應市場需求– 跨地區、跨幣別的即時、整合資訊

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資訊系統

1970年代 1980年代 1990年代 2000年代企業應用軟體 MRP MRP II ERP EERP

應用範圍 部門 工廠 企業 供應鏈資訊系統架構 Mainframe Minicomputer Client/Server Web Computing

需求重點 成本 品質 速度(交期) 協同規劃(彈性)

市場特性 大眾市場 區隔市場 利基市場 一對一少樣大量 多樣少量 多樣大量 大量客製生產模式

產品供給導向 客戶需求導向

資料來源 : 資策會 MIC IT IS 計畫

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企業應用軟體演變趨勢

E-Business( 電子企業環境 )

ESCM( 延伸型供應鏈管理 )

EERP( 延伸型企業資源規畫 )

E-Business( 電子企業環境 )

ESCM( 延伸型供應鏈管理 )

EERP( 延伸型企業資源規畫 )

E-Commerce( 電子商務 )

E-Commerce( 電子商務 )

SFA( 銷售自動化 )

SFA( 銷售自動化 )

CRM( 客戶關係管理 )

CRM( 客戶關係管理 )

SCM( 供應鏈管理 )

SCM( 供應鏈管理 )

ERP( 企業資源規畫 )

ERP( 企業資源規畫 )

MRP ( 物料需求規劃 )MRP ( 物料需求規劃 )

Payroll ( 薪資系統 )Payroll ( 薪資系統 )

GL ( 總帳會計 )GL ( 總帳會計 )

AP ( 應收帳款系統 )AP ( 應收帳款系統 )

AR ( 應付帳款系統 )AR ( 應付帳款系統 )

1970 1990 2000

EDI( 電子資訊交換 )

EDI( 電子資訊交換 )

Planning ( 計劃 )Planning ( 計劃 )

Scheduling ( 排程 )Scheduling ( 排程 )

Distribution ( 配銷 )Distribution ( 配銷 )

MRP II( 製造需求規劃 )

MRP II( 製造需求規劃 )

HR( 人力資源 )

HR( 人力資源 )

FMIS( 財務系統 )

FMIS( 財務系統 )

1980資料來源： HP簡報

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E-Business Application Architecture

=e-commerceE-business +ERP +SCM+MES/MCS +KM+CRM

Cu

stom

erEmployee

Su

pp

lier

E-P

roc

urem

ent

Cu

sto

me

r Re

latio

nsh

ip M

ana

gem

en

tEnterprise Applications Integration

Manufacturing Execution

Manufacturing Control

Knowledge Management

Supply Chain Management

Enterprise Resource Planning

Se

lling

Ch

ain

Man

ag

eme

nt

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製造環境分類• 以製造策略分類

– Job Shop ( 零工型 )– Repetitive ( 重複型 )– Batch ( 批量型 )– Flow Shop ( 流線型 )

• 以產品定位策略分類– Engineering-to-order– Make-to-order– Assemble-to-order– Make-to-stock

種類

數量

1

2

3

4

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製造環境

Repetitive production

Product

Job shop

Flowshop

CustomLow volume differentiated

High volume differentiated Commodity

Specialty chemicalsand drugs

AerospaceIndustrial machinery

Machine tools

Electrical and electronics

Paper Containers Brewers

AutomobileTire and rubberSteel products

Major chemicals and drugs

OilSteelForest products

Proc

ess

Source: Taylor et al., hy the Process Industries Are Different,?Production and Inventory Management Journal, 1981.

One-of-a-kind PERT/CPM

MRP; CRP

MRP; Line BalancingJIT

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Manufacturing System Model

Business Planning

Sales Planning

Production Planning

MPS

MRP

Demand Management Finance Planning

Resource Requirements Planning

Rough-Cut Capacity Planning

Capacity Requirements Planning

PurchasingProduction

Activity Control

Mid

Term

Lon

g-

Term

Sh

ort-

Term

Inventory Management

Input/OutputControl

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Capacity Management in MPS System

Resourcerequirements

planning

Rough-cutcapacity planning

Capacityrequirements

planning

Purchasing

Material requirements

planning

Message toBUY or MAKE

Production activity control

Master production scheduling

Productionplanning

Input/Outputanalysis

OperationSequencing

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Capacity Planning and Control

Priority

Capacity

Planning Control

PPMPSMRP

RRPRCCPCRP

Input/OutputControl

OperationSequencing

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Capacity Definition

• The rate at which work is withdraw from the system.

• The highest reasonable output rate which can be achieved with the current product specifications, product mix, work force, plant, and equipment. [APICS dictionary]

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Capacity Management

• The function of establishing, measuring, monitoring, and adjusting limits or levels of capacity in order to execute all manufacturing schedules. [APICS dictionary]

• Include– capacity planning– capacity control

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Work Center and Load• Work Center

– A specific production facility, consisting of one or more people and/or machines, which can be considered as on unit for purposes of capacity requirements planning and detailed scheduling. [APICS dictionary]

• Load– The amount of scheduled work ahead of a

manufacturing facility, usually expressed in terms of hours of work or units of production. [APICS dictionary]

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Wight’s Funnel

CAPACITY

LOAD

OUTPUT

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Capacity and Load [APICS]

Capacity Load

( 每一作業之 Setup 及 run times)

工程研發工單PM

重工工單

計劃工單

已發放工單

加班及外包

考慮人員 , 設施 , 之available hours及Time Efficiency Rate

減項 Breaks, Downtime, Rework Absenteeism, Daily, Maintenance, Other

Capacity Planning Terms

LoadLoad

AvailableAvailable

WeekWeek

Hours per Hours per resourceresource

Capacity Utilization Scenarios

LoadLoad AvailableAvailable

LoadLoad

AvailableAvailable LoadLoad

AvailableAvailable

BalancedBalanced UnderloadedUnderloaded OverloadedOverloaded

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Determining Capacity Available

• Demonstrated (Measured) Capacity– the average recent output actually

achieved , is figured from historical data

– is defined as average output, not max output

• Rated (Calculated) Capacity– available hours ×utilization ×efficiency

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6% 6%

62%

13%

13%Breaks

R. Maintenance

Run Time

Un-utilized butscheduled time

Setup Time

Utilization

Actual time used (run and setup)

Scheduled time intended for productionUtilization =

A measure of how intensively a resourceis being used….

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Utilization

Example:

Breaks: 20 minutes per shiftRoutine maintenance: 10 minutes per shiftRun time charged: 6 hoursSetup time: 0.5 hour

Utilization =

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Efficiency

• A measure of how closely predetermined standards are achieved.

Actual output (standard hours earned)Standard output expected (scheduled)

efficiency =

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EfficiencyExample:

Work center: 3 machines, two 8-hrs shifts, five days a weekBreakdown: 12 hrs per week

Utilization =

records indicate that the work center produced an average of 250.8 sta. Hours of output.Efficiency =Capacity =

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Capacity DeterminationShift per Day

Machines or Work Stations

Hours per Shift

Days per Week

Utilization

Efficiency

= Standard Hours per Week

Ex: Shifts = 3Shift Length = 8 hrs5 Days per WeekNumber of Machines = 6Machine Utilization = .8Efficiency = .9

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Rough-Cut Capacity Planning

• The need for long planning horizons and the lack of specific, accurate data for many important factors make RCCP techniques more practical than detailed calculations

• A capacity plan should not be deferred; rough-cut approaches are very practical

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Bill of Resource (Bill of Labor)

• 資源清單 (BOR; BOL) 乃針對製造料件或零件群時，所需之主要關鍵資源的產能需求條列。

• 不是為了作為途程 (Routing) 用途。• 只是一種估計特定料項所需產能的方法。

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RCCP Procedure

• Converting units of product in the MPS to standard hours of work in individual centers

• To accumulate in each period in the MPS the total hours of work required to produce all products scheduled in that period– no LT offsetting– no lot-sizing– no significant changes in inventories of items

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Routing for Product X

Product XSEQSEQ Work CenterWork Center UsageUsage

OP 1 1 OP 1 1 0.1 hrs/pc0.1 hrs/pcOP 2 2OP 2 2 0.5 hrs/pc 0.5 hrs/pc

1 2 43 8765

PERIODS

Planned Order Released

Product X

100 50 80 100 40 60 90

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Routing for Assy-01

Assy-01

1 2 43 8765

PERIODS

Planned Order Released

Assy-01

SEQSEQ Work CenterWork Center UsageUsage

OP 1 2 OP 1 2 0.2 hrs/pc0.2 hrs/pcOP 2 3OP 2 3 0.8 hrs/pc 0.8 hrs/pc

100 50 80 200 180 40 60 90

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Resource Load Profile

Work Center 2

0

50

100

150

200

250

1 2 3 4 5 6 7 8

Period

Load

Others

Assy-01

Pro X

Capacity

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BOM for FG

階層 零件 數量/母項 說明 0

1

2

2

100

110

121

122

1

2

6

10

FG

subassembly

component A

component B

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Item Master Files for FG

Item OrderQuantity

On Hand On Order DueDate

Lead Time Allocated

100110121122

L4L400

24006000

0500

15002500

250400

24006000

7/37/107/107/10

1 week2 weeks3 weeks4 weeks

0000

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Routing Files for FG

Parts WorkCenter

Setup Time/Lot Run Time/Piece

100 1 30 min 2.5 min110 2

110 min15 min

0.75 min0.50 min

121 312

15 min25 min15 min

0.30 min0.25 min0.25 min

122 2313

25 min30 min75 min30 min

0.75 min0.15 min0.50 min0.75 min

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Work Center Master Files

WorkCenter

Available(min)

Utilization Efficiency PlannedQueue

123

2,4002,4002,400

100%100%100%

100%100%100%

4 days4 days4 days

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MPS for Part 100

Week1 2 3 4 5 6 7 8 9 10 11 12

Quantity 250 200 250 150 200 300 150 250 200 200 250 200

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RCCP-Process Time Computation

Part Opn. LS SU Run Process Qty/FG Total WC100 1 200 30 2.50 2.650 1 2.650 1110 1 400 10 0.75 0.775 2 1.550 2110 2 400 15 0.50 0.538 2 1.076 1121 1 2400 15 0.30 0.306 6 1.836 3121 2 2400 25 0.25 0.260 6 1.560 1121 3 2400 15 0.25 0.256 6 1.536 2122 1 6000 25 0.75 0.754 10 7.540 2122 2 6000 30 0.15 0.155 10 1.550 3122 3 6000 75 0.50 0.513 10 5.130 1122 4 6000 30 0.75 0.755 10 7.550 3

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RCCP-BOR Computation

Part LS SU Prcess Run Qty/FG Total WC WCtotal

100 400 15 0.5 0.538 2 1.076 1122 6000 75 0.5 0.513 10 5.130 1121 2400 25 0.25 0.260 6 1.560 1100 200 30 2.5 2.650 1 2.650 1 10.416121 2400 15 0.25 0.256 6 1.536 2110 400 10 0.75 0.775 2 1.550 2122 6000 25 0.75 0.754 10 7.540 2 10.626122 6000 30 0.15 0.155 10 1.550 3122 6000 30 0.75 0.755 10 7.550 3121 2400 15 0.3 0.306 6 1.836 3 10.936

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Rough Cut Capacity Requirements

WeekWork Center 1 2 3 4 5 6 7 平均

123

260426572734

208321252187

260426572734

156215941640

208321252187

312531883281

156215941640

223222772343

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RCCP

0

500

1000

1500

2000

2500

3000

3500

1 2 3 4 5 6 7

WC1

WC2

WC3

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RCCP

A11 A12

A22A21

WC1

WC2

P1 P2

B11 B12

B22B21

P1

P2

M1 M2

C11 C12

C22C21

WC1

WC2

M1 M2

RCCP

MPSBOR

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Backward and Forward Scheduling

OP NOP N-1OP 1 ………

Forward scheduling

Backward scheduling

Order Due Date

Order Start Date

OP N-1

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Infinite and Finite Loading

Infinite

Finite

Capacity

Capacity

0

50

100

150

200

Period

Load

Load 104 120 180 130 97 125 110 150

1 2 3 4 5 6 7 8

0

50

100

150

200

Period

Load

Load 110 120 120 120 105 120 110 120

1 2 3 4 5 6 7 8

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CRP Definition• The function of establishing, measuring,

and adjusting limits or level of capacity

• The process of determining in detail the

amount of labor and machine resources

required to accomplish the tasks of

production [APICS Dictionary]

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Capacity Requirements Planning

CapacityRequirements

Planning

CapacityRequirements

Planning

Planned orders Planned orders Released ordersReleased orders

RoutingRouting Work centerWork center

Work center load reportWork center load report Revised schedule Revised schedule

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Manufacturing Order and Routing

• Manufacturing Order (Work Order)– A document, group of documents, or schedule

identity conveying authority for the manufacture of specified parts or products in specified quantities. [APICS dictionary]

• Routing– A set of information detailing the method of

manufacture of a particular item. It includes the operations to be performed, their sequence, the various work centers to be involved, and the standards for setup and run (times). [APICS dictionary]

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Inputs Needed for CRP • Open Order File• Planned Order Releases• Routing File

– operations to be performed– sequence of operations– work centers to be used– possible alternate work centers– tooling needed at each operation– standard times: setup times, run times

• Work Center File– move time, wait time, queue time

• Shop Calendar

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Lead Time

• Manufacturing LT– queue, setup, process, wait, move

• Average Q– (SU+RT)1+(SU+RT)2+…+(SU+RT)n

queue setup process wait move

1 2 n W/C……..

WIP

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Expected Queueing Time

Activation

QueueingTime

0.8 0.84 0.88 0.92 0.96 1.00

Assumption: M/M/1queueing systemE(Q) = a/[s(a-s)] ; a: ave. arrival rate ; s: ave. service rateActivation = a/s

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A Revised Definition of Capacity Available

• Capacity available = Time available Efficiency Availability Activation

• Availability– 1- the fraction of time down due to machine

breakdown and/or absenteeism

• Activation– 1- the fraction of down due to lack of work

UTILIZATION

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How Load Is Determined?• The production plan

– long range rate of production

• The MPS drive MRP– MRP generate planned orders– released (open) orders

• CRP (capacity requirements planning)– calculates std hours required, by W/C, by time

period, based on planned and open orders

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Load Determination

• Open Orders (from order file status file maintained by production control)

– order due date– order quantity– operations completed– operation remaining

• MRP-planned Order Releases ( from MRP’s output)

– planned order release date– planned order receipt date– planned quantity

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Data Requirements for CRP

• Valid due dates on all released and planned orders

• Up-to-date routings and processing information• Accurate standards for setup and processing time• A scheduling program to handle all operations• A loading program to assign work to time periods• Standard queue allowances for all work centers• Estimates of load due to unplanned occurrences

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MRP for FG

料件 100

固定期間訂購; 訂購期間: 1; 前置時間: 1

期間 0 1 2 3 4 5 6 7

毛需求排程到貨預估在手量計劃核發

250 200 250 150 200 300 150 250

料件 110

固定數量訂購; 訂購數量: 400; 前置時間: 2

期間 0 1 2 3 4 5 6 7

毛需求排程到貨預估在手量計劃核發

400

料件 121

固定數量訂購; 訂購數量: 2400; 前置時間: 3

期間 0 1 2 3 4 5 6 7

毛需求排程到貨預估在手量計劃核發

2400

料件 122

固定數量訂購; 訂購數量: 6000; 前置時間: 4

期間 0 1 2 3 4 5 6 7

毛需求排程到貨預估在手量計劃核發

6000

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CRP Computation

• Setup time computation for planned order

• Run time computation for planned order

• Setup time computation for open order

• Run time computation for open order

• CRP load report

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Planned Order Releases

WeekPart 1 2 3 4 5 6 7100110121122

200400

24006000

250400

00

150500

24000

200400

06000

300400

24000

150400

24000

250400

00

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Setup Time Matrices for FG

週零件 1 2 3 4 5 6 7

WC1 100110121122合計

3000030

301525070

3015075120

301525070

30150045

30152575145

301525070

WC2 100110121122合計

01002535

0100010

01015025

01002535

01015025

0100010

01015025

WC3 100110121122合計

0015015

0003030

0015015

0003030

00153045

0015015

0003030

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Run Time Matrices for FG週

零件 1 2 3 4 5 6 7WC1 100

110121122合計

500000

500

6252006000

1425

375200

030003575

500250600

01350

75020000

950

37520060030004175

625200600

01425

WC2 100110121122合計

03000

45004800

030000

300

0375600

0975

0300

045004800

03006000

900

0300

00

300

0300600

0900

WC3 100110121122合計

00

6000

600

000

900900

00

6000

600

000

21002100

00

600900

1500

00

6000

600

000

21002100

65

Capacity Req. of Planned Releases

週1 2 3 4 5 6 7

WC1 530 1495 3695 1420 995 4320 1495

WC2 4835 310 1000 4835 925 310 925

WC3 615 930 615 2130 1545 615 2130

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Capacity Req. by Released Orders

part Workcenter

week Setup time Run timecalculation

Run time Total time

100110110121121122122

1211213

1121212

30101525157530

2502.54000.754000.5

24000.2524000.2560000.5

60000.75

62530020060060030004500

655310215625615

30754530

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Capacity Requirements Plan for FG

週1 2 3 4 5 6 7

WC1 4885 1710 3695 1420 995 4320 1495

WC2 5145 925 1000 4835 925 310 925

WC3 615 5460 615 2130 1545 615 2130

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CRP

0

1000

2000

3000

4000

5000

6000

1 2 3 4 5 6 7

WC1

WC2

WC3

69

W/C Capacity vs. Average Load

• The formal plan does not include all the load it will be necessary to handle– new products not in the current MPS– use of alternate routings and processing – scrap replenishment and rework operations– additional processing needed for any reason– record errors resulting in additional material

requirements

• Some of the load must remain in the center to provide the planned standard queue

70

Input/Output Control

Input RateControl

Output RateControl

Queue(WIP, Load)

71

Input/Output Control• Input/Output control is a method to

manage queues and work-in-process lead times

• Input/Output Control ReportWeek Ending: 06/06 06/13 06/20 06/27 07/03 07/10 07/17InputPlanned 182 203 172 178 193 205 208Actual 197 180 168 191 189Cum Deviation 15 -8 -12 1 -3Output Planned 207 207 207 207 207 207 207Actual 213 202 206 210 212Cum Deviation 6 1 0 3 8QueueBegging: 300 hrsPlanned 275 271 236 207 193 191 192 Actual 284 262 224 205 182

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Definition• Planned Input

– Work expected to arrive by time period• based on CRP constraints• expressed in standard hours or other common

unit of measure

• Planned Output– Work to be reduced by time period

• to reduce queue, plan output greater than input• make capacity available

73

Definition• Planned Queue

– Beginning queue + planned input - planned output• week ending 06/06 : 300 + 182 - 207 = 275• week ending 06/13 : 275 + 203 - 207 = 271• continuing for each succeeding week

• Actual Input– Work arriving at work center by time period, same

unit of measure• obtained from reporting systems or manual logs• affected by releases to shop, flow from prior operations

74

Definition• Actual Input

– Work arriving at work center by time period, same unit of measure

• obtained from reporting systems or manual logs

• affected by releases to shop, flow from prior operations

• Actual Output– Standard hours produced during each period

• from reporting systems or manual logs

• affected by resources, efficiency, workload

75

Definition• Actual Queue

– Begging (or prior period) queue + actual input - actual output

• week ending 06/06: 300 + 197 -213 = 284• verified periodically to confirm accuracy of input

and output data

• Control– measure actual to plan

• actual output vs. planned output• actual output vs. actual input• actual input vs. planned input

76

Input/Output Comparisons

• Actual output planned output– Queues, LT – not enough input? Insufficient capacity?

• Actual output planned output– may run out of work, excess capacity

• Actual input planned input– may run out of work– feeding w/c behind schedule, late order

77

Input/Output Comparisons

• Actual input planned input– work released early, queue & LT – feeding w/c ahead of schedule

• Actual output actual input– work released early, queue & LT – not enough capacity

• Actual output actual input– work released late, may run out of work– feeding w/c behind schedule, idle

capacity, late order

Dispatching Rules

• First come, first served (FCFS)

• Earliest Job Due Date (EDD)

• Earliest Operation Due Date (ODD)

• Operation start dates

• Critical ratios (CR)

• Shortest process time (SPT)

• Other methods

79

Dispatching Rules

Dispatching RuleJob ProcessTime(days)

ArrivalDate

DueDate

OperationDue Date

FCFS EDD ODD SPT

A 4 223 245 233 2 4 1 3

B 1 224 242 239 3 2 2 1

C 5 231 240 240 4 1 3 4

D 2 219 243 242 1 3 4 2

80

Capacity Management

PlanningHorizon

Extent TimePeriods

Decisions Techniques

Resourceplanning

(long range)

Beyondone year

MonthlyQuarterly

Yearly

Plant constructionEquipment Proc.

Manpower planning

Grosscalculation

BOL

Operatinghorizon plan

(medium range)

Up toone year

Weekly Manpower transfersWork plan adjustments

Alternate routingMake/Buy

Subcontracting

Capacityrequirements

planning

Execution(short range)

One tofour

weeks

DailyWeekly

Order releaseOvertime

Alternate routingOrder overlapping

OperationsequencingI/O control

81

製造環境特性特性 Job Shop Repetitive/Batch

產品定位策略 Make-to-order Make-to-stock

Engineer-to-order Assemble-to-order

產量 低 高批量 分攤 setup cost 1

Queue, move, wait time 高 (70% ~90%) 低產能 Standard hours Cycle time

Routings 變動 固定Dispatching 複雜 FCFS

layout 功能別佈置 產品別佈置SFC 推式 (push) 拉式 (pull)

Reporting detail 高 低

82

製造環境比較

One-of-a-Kind

Fixed location

Fixed byjob site

Trucks,cranes

Single product

High

Very long

Satellites,construction

PlantOrganization

Routing

MaterialHandling

Product Mix

Amount WIP

Time toManufacture

Examples

Job Shop

Variable byproduct

Functionaldepartments

Fork lifts,tote bins

Many products

High

Variable byproduct

Tools,furniture

Repetitive

Fixed byassembly line

Fixed by line

Conveyors,containers

Similar products

Low

Short

Auto assembly,tires

Flow Shop

Fixed by plant

Fixed by plant

Conveyors,pipelines

Similar products

Low

Short withlong runs

Oil, steel,cement

Source: APICS, CPIM materials 1998

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Conclusions• Managing order LTs requires managing bot

h priority and capacity

• Capacity plans should use the broadest possible product groups that go through similar manufacturing operations

• Capacity must be adequate to support the MPS and handle additional unplanned demands