1. Constraint Management
Chapter 7 1

2. How Constraint Management fits the Operations Management Philosophy
Operations As a Competitive
Weapon
Operations Strategy
Project Management
Process Strategy
Process Analysis
Process Performance and Quality
Constraint Management
Process Layout
Lean Systems
Supply Chain Strategy
Location
Inventory Management
Forecasting
Sales and Operations Planning
Resource Planning
Scheduling

3. Eastern Financial Florida Credit Union
What was the problem?
How did they solve it?

4. Capacity Planning
Capacity is the maximum rate of output of a process or system.
Output Measures
Input Measures
Utilization

5. Output and Capacity What is a Constraint? A Bottleneck
Any factor that limits system performance and restricts its output.
A Bottleneck
An output constraint that limits a company’s ability to meet market demand.
Also called Capacity Constraint Resource or CCR

6. Theory of Constraints (TOC)
A systematic approach that focuses on actively managing constraints that are impeding progress.
Constraint Management
Short-Term Capacity Planning
Theory of Constraints
Identification and management of bottlenecks
Product Mix Decisions using bottlenecks
Long-term Capacity Planning
Economies and Diseconomies of Scale
Capacity Timing and Sizing Strategies
Systematic Approach to Capacity Decisions

7. 7 Key Principles of TOC
The focus is on balancing flow, not on balancing capacity.
Maximizing output and efficiency of every resource will not maximize the throughput of the entire system.
An hour lost at a bottleneck or constrained resource is an hour lost for the whole system.
An hour saved at a non-constrained resource does not necessarily make the whole system more productive.

8. 7 Key Principles of TOC
Inventory is needed only in front of the bottlenecks to prevent them from sitting idle, and in front of assembly and shipping points to protect customer schedules. Building inventories elsewhere should be avoided.
Work should be released into the system only as frequently as the bottlenecks need it. Bottleneck flows should be equal to the market demand. Pacing everything to the slowest resource minimizes inventory and operating expenses.

9. 7 Key Principles of TOC
Activation of non-bottleneck resources cannot increase throughput, nor promote better performance on financial measures.
Every capital investment must be viewed from the perspective of its global impact on overall throughput (T), inventory (I), and operating expense (OE).

10. Application of TOC Identify The System Bottleneck(s).
Exploit The Bottleneck(s).
Subordinate All Other Decisions to Step 2
Elevate The Bottleneck(s).
Do Not Let Inertia Set In.

11. Bal Seal Engineering Managerial Practice 7.1
Theory of Constraints in Practice
Bal Seal had problems with excessive inventory, long lead times and long work hours.
They were operating above capacity but on-time shipment rate was 80-85%
Bal Seal implemented TOC with dramatic and almost immediate results.
Excessive inventory dried up
Extra capacity was experienced everywhere but at the constraint
Total production increased over 50%
Customer response time decreased from 6 weeks to 8 days
On-time shipments went up to 97%

12. Identification and Management of Bottlenecks
A Bottleneck is the process or step which has the lowest capacity and longest throughput.
Throughput Time is the total time from the start to the finish of a process.
Bottlenecks can be internal or external to a firm.

13. Setup Time
If multiple services or products are involved, extra time usually is needed to change over from one service or product to the next.
This increases the workload and could be a bottleneck.
Setup Time is the time required to change a process or an operation from making one service or product to making another.

14. Where is the Bottleneck? Example 7.1
1. Check loan documents and put them in order
(10 minutes)
2. Categorize loans
(20 minutes)
3. Check for credit rating
(15 minutes)
6. Complete paperwork for new loan
4. Enter loan application data into the system
(12 minutes)
Customer
5. Is loan approved?
(5 min)
Yes No

15. Barbara’s Boutique Application 7.1
Two types of customers enter Barbara’s Boutique shop for customized dress alterations. After T1, Type A customers proceed to T2 and then to any of the three workstations at T3, followed by T4, and then T7. After T1, Type B customers proceed to T5 and then T6 and T7. The numbers in the circles are the minutes it takes that activity to process a customer. T1
(12) T6
(22) T5
(15) T2
(13) T7
(10) T4
(18)
T3-a
(14)
T3-c
(11)
T3-b
Type
Type A
Type B
What is the capacity per hour for Type A customers?
If 30% of customers are Type A customers and 70% are Type B, what is the average capacity?
When would Type A customers experience waiting lines, assuming there are no Type B customers in the shop?
Where would Type B customers have to wait, assuming no Type A customers?

16. Long-Term Capacity Planning
Constraint Management
Short-Term Capacity Planning
Theory of Constraints
Identification and management of bottlenecks
Product Mix Decisions using bottlenecks
Long-term Capacity Planning
Economies and Diseconomies of Scale
Capacity Timing and Sizing Strategies
Systematic Approach to Capacity Decisions

17. Long-Term Capacity Planning
Deals with investment in new facilities and equipment.
Plans cover a minimum of two years into the future.
Economies of scale are sought in order to reduce costs through
Lower fixed costs per unit
Quantity discounts in purchasing materials
Reduced construction costs
Process advantages

18. Average unit cost (dollars per patient)
Economies of Scale
Economies of scale occur when the average unit cost of a service or good can be reduced by increasing its output rate.
Diseconomies of scale occur when the average cost per unit increases as the facility’s size increases
250-bed hospital
500-bed hospital
750-bed hospital
Economies of scale
Diseconomies of scale
Output rate (patients per week)
Average unit cost (dollars per patient)

19. Capacity Timing and Sizing Strategies
Sizing Capacity Cushions
Timing and Sizing Expansions
Linking Process Capacity and other operating decisions.

20. Capacity Cushions
A capacity cushion is the amount reserve capacity a firm has available.
Capacity Cushion = 100% − Utilization Rate (%)
How much capacity cushion depends on
The uncertainty and/or variability of demand
The cost of lost business
The cost of idle capacity 23

21. Capacity Expansion Expansionist Strategy
Staying ahead of demand
Planned unused capacity
Time
Capacity
Forecast of capacity required
Time between increments
Capacity increment 23

22. Capacity Expansion Wait-and-See Strategy
Chasing demand
Time
Capacity
Forecast of capacity required
Planned use of short-term options
Time between increments
Capacity Increment 28

23. Linking Process Capacity and Other Decisions
Competitive Priorities
Quality
Process Design
Aggregate Planning