Glossary · Manufacturing systems
Work in process (WIP)
Also known as: WIP, Work in progress
German: Umlaufbestand
In manufacturing, work in process (WIP) is the material and partly finished products that have entered production but are not yet finished goods, including items waiting between operations.
- Manufacturing systems
In one sentence
Work in process (WIP) is material and partly finished products that have entered production but aren't finished goods yet.
Example
Between turning and grinding, 600 shafts wait in containers, which accounts for most of the line's work in process.
How it applies
- Operation: WIP ties up capital and space and lengthens lead times. Little's law links it to throughput and lead time; limiting WIP is a core lean principle.
- Analysis: WIP builds up before the Bottleneck; tracking WIP by location helps to find constraints.
- Traceability: WIP must remain identifiable, with batch or serial numbers and status, so it can be found in a recall or quality hold.
- Documentation: Document WIP limits, storage locations and labeling rules for partly finished items. Instructions for quality holds should say how affected WIP is identified and blocked.
Work in process vs. inventory
Inventory is the broader term: raw materials, WIP and finished goods. WIP refers only to what is currently in production.