What is a work order in manufacturing?

The work order is the parent record. Job cards, material issue slips, labour entries and NCRs all point to it. That is what lets the system answer where job 1042 is and what it cost from the same place.

• Item, quantity and unit of measure to produce
• BOM revision and the material lines derived from it
• Routing: operations in sequence, each at a work centre with expected time
• Planned start and due date, and the customer order it serves, if any
• Status: planned, released, in progress, complete, closed
• Actuals as they accumulate: issues, returns, labour, scrap, inspections

Planned: the order exists so that material requirements and capacity can be seen, but nothing has been committed. Released: the shop may start; material is reserved or issued and job cards print. In progress: operations are being reported, labour logged and scrap recorded. Complete: the quantity is finished and received into stock as finished goods or shipped. Closed: no further transactions are accepted and the cost is final. Each change of status is a good place for a rule: do not release without material on hand, do not close with an open NCR, notify the office when the last operation completes. Keep the statuses few. Shops that invent ten statuses end up with orders stuck in the wrong one.

Releasing a work order does not move stock. Issuing material does: each issue posts a movement from the warehouse to the job, at the cost on the ledger, and that cost lands on the work order. Returns post the opposite. Labour logged at a work centre multiplies hours by the centre's rate and adds to the same order. When the finished quantity is received, stock increases by that quantity at the accumulated cost per unit, and the job's work in progress drops to zero. This is why work orders and stock cannot live in separate systems without a reconciliation problem: the same transaction feeds both.

A 10 to 50 person shop does not need an elaborate work order. It needs one that the supervisor raises in under a minute, prints with a barcode and can scan at each step. It needs material issue to be as fast as handing over the sheet, or the issue will be recorded tomorrow, or never. And it needs the close to be a deliberate act by someone who checks that scrap and labour are in before the cost is reported. Batch sizes are small, so many shops raise one work order per customer order line. Repeat parts made for stock get a work order per batch, released from a reorder point.