Stock policies

The Stock policies screen answers a question the requirements plan does not: how much of an item should be kept on hand at all times. It is a building block of the Supply module (supply).

A policy says “how much to keep”. It does not say “where to get it”: the choice to buy (from an external supplier) or replenish internally (from another warehouse) happens at commitment time, not here.

Scope and precedence

A policy applies to an item, at one of three scopes:

  • The whole instance — the default rule, everywhere.
  • A site — overrides the instance rule for that site.
  • A warehouse — overrides everything, for that specific warehouse.

On resolution, the most specific wins: warehouse, then site, then instance — the first (active) scope found prevails, with no blending. A policy is a coherent whole: you do not mix a warehouse minimum with an instance lead time. With no policy at all, the instance default lead time applies and no threshold is set.

What a policy holds

  • Reorder point — the level that triggers a replenishment. It is a floor drawn on the projected stock curve, not extra demand: it never adds to the requirements plan (that would double-count).
  • Safety stock, minimum / maximum quantity.
  • Lead time — overrides the instance default.
  • Minimum order quantity, order multiple — purchasing constraints.
  • Minimum remaining shelf life on arrival — for a perishable item, the fraction of shelf life required on receipt (a standard supplier clause).
  • ABC class — classification by consumption value.

Structure and input are set here; we do not pretend to compute the reorder point. An honest statistical suggestion (intermittent demand, slow movers) will come in a later phase. A “computed” reorder point without reliable history would be false precision.

Two views

A selector at the top switches between:

  • Defined policies — the list of existing policies (default view).
  • Items without a policy — spotting the omissions: items that are actually used (referenced in a maintenance bill of materials, or present in stock) but have no policy. It does not list the whole catalog (the vast majority of items have no policy — that would be noise), only the ones that matter. Each row shows why the item surfaces (a “Demand” and/or “Stock” badge) and offers a “Create policy” button that opens the form with the item pre-selected.

Filters

Search by item, plus scope and ABC class (multi-select), an active only filter, and a safety criticality — Critical (CSI) filter. ABC class (consumption value) and the CSI flag (flight-safety-critical item) are two separate axes: a cheap gasket that grounds an aircraft is still a critical item, regardless of its ABC class. A dedicated CSI column, distinct from the ABC Class column, shows them side by side.

See also