CH: 6 Constraint Management



Constraint- any factor that limits the performance of a system and restricts it output



Bottleneck- the capacity constraint resource whose available capacity limits the organization’s ability to meet the product volume or mix, or demand fluctuations 



Theories of constraints:

  1. Identify the system bottleneck(s)

  2. Exploit the bottleneck(s)

  3. Subordinate all other decisions to Step 2

  4. Evaluate the bottleneck(s)

  5. Do not let inertia set in/repeat



Key Principle of the TOC:

-focus should be on balancing flow, not on balancing capacity 

-maximizing the output and efficiency of every resource may 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 saves does not make the system more productive)

-inventory is only needed in front of bottlenecks and in front of assembly and shipping points 

-work should be released into the system only as frequently as needed by the bottlenecks (bottlneck flows=market demand)

-activating a non-bottleneck resources is not the same as utilizing a bottleneck (it doesn’t increase throughput or promote better performance)

-every capital investment must be viewed from the perspective of the global impact on throughput, inventory and operating expense