Two different things with one name
These get used interchangeably and they are not the same, which causes real
problems once traceability matters.
A work order is an instruction: make 200 of this, using this BOM, by this
date. It is a plan. It exists before anything is produced and it can be changed
or cancelled without anything physical having happened.
A production batch is an outcome: this specific run, on this date, consuming
these specific component lots, producing this specific quantity that carries a lot
number. It is a record of what happened.
One work order can produce several batches. A batch always belongs to something
that was made.
Why the distinction matters
Because they answer different questions, and using one where you needed the other
loses information you cannot get back.
- Planning works from work orders. What is scheduled, what materials are
committed, what capacity is spoken for.
- Traceability works from batches. Which lots went in, what came out, who ran
it, and which orders it shipped in.
- Costing needs both. The work order carries the standard; the batch carries
the actual. The gap between them is the variance, and the variance is where
margin quietly goes.
A system that only models work orders can tell you what should have happened. It
cannot tell you what did.
The split-batch case
The distinction becomes concrete the moment a work order does not complete in one
run. A 200-unit order made as two runs of 100 on different days, possibly with
different component lots, is one work order and two batches.
If those two runs collapse into one record, they inherit a single lot number and
any future trace covers both. You have doubled the scope of every recall that
touches either one, in exchange for one less row.
In IEMSuite
Production batches are the unit of record. Each one consumes specific lots by FIFO
or FEFO, records actual against planned quantity, carries its own lot number and
build date, and links forward to the orders it fulfilled.
FAQ
Is a manufacturing order the same as a work order?
Broadly yes, and different systems use different words for it. What matters is
whether the term refers to the instruction or the output, because some products
use a single object for both and that is where traceability gets thin.
Should one work order always be one batch?
Only when it runs in one go with one set of component lots. Split it across days,
shifts or lots and it should be separate batches, or the trace widens to cover
material that was never involved.
Which one carries the lot number?
The batch. The lot number identifies physical output, and a work order has no
physical output until a batch produces it.