pullonkaula

Pullonkaula is a term used in production engineering and operations management to describe a point in a process where throughput is constrained by the capacity of a single resource or operation. The bottleneck typically determines the system’s overall output, drives the cycle time, and causes accumulation of work-in-progress upstream. Although the exact location of a bottleneck can shift over time, the constraint remains the rate-limiting factor for the whole process.

Common causes include an operation with a longer cycle time than others, equipment failures or maintenance downtime, imbalanced line design, variability in task times, and upstream supply delays. The presence of a bottleneck usually leads to queues before the constrained station and underutilization of non-bottleneck resources after it. The effect is longer lead times and higher WIP in front of the bottleneck, while other parts of the system may be idle or underused.

To identify pullonkaula, analysts use capacity analysis, time studies, value stream mapping, and observation of where queues form. Little’s law and related throughput calculations help quantify the impact on overall performance. Measuring the throughput of each operation and its cycle time helps pinpoint the slowest link in the chain.

Management strategies aim to elevate, exploit, or subordinate the bottleneck. Examples: ensure the constrained resource is never idle; synchronize upstream and downstream processes to its pace; add capacity at the bottleneck or create parallel resources; reduce variability with standardized work and SMED; implement buffers to protect the bottleneck; adopt pull-based systems such as Kanban to regulate work-in-progress.

Contexts include manufacturing lines, logistics networks, software build pipelines, and healthcare processes, where improving bottlenecks yields significant gains in throughput and lead time. Bottlenecks are not fixed and can move as improvements shift capacities, requiring ongoing monitoring.