Stock on risk, not on forecast
For mining and heavy industry, items that move two to four times a year are a risk-management problem, not a forecasting problem.
The challenge
A common mistake is to treat a critical, rarely used part like any other item: forecast its demand, apply a standard safety stock formula, and assume the answer is right. For slow movers with long lead times, this usually produces poor results.
Start with consequence, not frequency
What happens if the part is unavailable?
How long can the operation survive without it?
Is there an alternative? Can it be repaired or transferred from another site?
What is the true replenishment lead time?
Not all slow movers are the same
Critical long-lead parts, repairable components, non-critical specialist items and cheap consumables each need a different approach. Which approach applies is set by your own criticality model and rules.
Review slow movers every year
Many slow movers become obsolete because the equipment disappeared, not because the policy was wrong. Review installed base, retired equipment, lead times, alternate suppliers, repair options, last demand date and fleet plans.
A two-stage decision: first whether to stock, based on criticality, supply risk, lead time, alternatives and repairability; then how much.