Production: work orders, routings, counts, lots

The model

• Products have an item class (raw, wip, finished, operations, spare part), a unit, and a tracking mode: none, lot, or serial. A product is either bought (it has vendors) or made (it has a recipe: the components one unit consumes, in whole units).
• Work centers group machines that can run the same operations.
• Task types are the operations: cut, form, weld, inspect. Each has its standard setup and run minutes, the work center it runs in, its parameter set (machine settings, versioned) and its form.
• Routings list the steps a product goes through, each a task type. A step can be a gate: the steps after it wait until it's done. Changing a routing creates a new version; released orders keep the version they started with.
• Work orders ask for a quantity of a product. Status: draft → released → in progress → completed → closed (or cancelled).

Release

Releasing a work order (work_orders.release, which needs Release work orders) creates one operation task per routing step:

• on the step's machine, when its work center has exactly one;
• with the parameter set's released version pinned;
• each step after a gate waiting on it, through a dependency.

Its preview lists each operation it would create. Work orders usually come from an ERP: work_orders.upsert and work_orders.batch_upsert create and update draft orders by your system's id.

Counts

• During a run, tasks.record_counts adds good and scrap quantities. Counts add up and feed OEE.
• At completion, a producing task needs its counts. They come either with the completion or from the counts recorded during the run.
• Completing posts the output:
  • the good quantity goes into stock;
  • the recipe is consumed (backflushed) from the order's kit cart, then the machine's line-side storage, then any goods bin, earliest lot expiry first.
• A work order completes by itself when its last operation is done.

Lots and genealogy

• Receiving a lot-tracked product records its lot.
• Completing a work order for a lot-tracked product creates the produced lot.
• Consumption links one to the other, so a finished lot traces back to its supplier lots.
• Blocked and quarantined lots are never consumed or shipped.

Downtime and OEE

Machines report stops from telemetry, or people report them. Stops are classified with reason codes. analytics.oee, analytics.downtime and downtime_events.summary turn counts, stops and standard times into availability, performance and quality.