How do you calculate protected days of supply?

Take on-hand inventory and divide by daily usage after accounting for safety stock through the lead-time factor. With 1200 pieces on hand, 85 used per day, and the safety-stock factor applied, the result is about 12.83 protected days of supply.

What is the difference between protected and unprotected days?

Unprotected days is simply inventory divided by daily usage — here 1200 ÷ 85 = 14.12 days. Protected days, 12.83 here, discounts that figure for safety stock and lead-time risk, giving a more conservative reorder trigger.

What is a good inventory turns figure for a scrap yard?

It depends on feed volatility and storage cost. Faster turns free up cash and yard space but raise stockout risk; slower turns buffer supply gaps. Aim for enough protected days to cover your supplier lead time plus a margin — roughly 13 days here gives a solid reorder cushion.

How do daily usage and lead time affect required inventory?

Required inventory is cycle stock — daily usage times lead time — plus safety stock. Higher usage or longer lead time both raise the inventory you must hold to avoid starving the line, which is why volatile feeds need fatter buffers.

Why size safety stock separately?

Cycle stock covers expected demand over the lead time; safety stock absorbs the variability around it. Without that buffer, any spike in processing or delay in inbound scrap pushes you below the line and idles equipment.

How do I lower the cash tied up in yard inventory?

Shorten supplier lead time, tighten safety stock as your feed becomes more predictable, and reorder more frequently in smaller lots. Each reduces the cycle and safety stock you must carry, raising turns without raising stockout risk.

Metal Recycling, Scrap Processing & Salvage calculator

Yard inventory turns Calculator

Yard inventory turns tells a scrap-processing or salvage operation how many days of supply its on-hand inventory actually buys before replenishment is needed. In metal recycling, feedstock arrives unevenly and processing lines must keep running, so knowing your protected days of supply prevents both starved shears and yards choked with idle material. Yard managers, buyers, and operations planners use it to set reorder points, justify safety stock, and balance working capital tied up in piles against the risk of a line running dry. Misjudge it and you either stall production or bury cash in inventory that turns too slowly.

What this calculator does

Estimate yard inventory turns for metal recycling, scrap processing and salvage using production-ready inputs so teams can plan replenishment and safety stock using actual usage and lead time.
Use it when yard inventory turns in metal recycling, scrap processing and salvage is being sized for a buffer or safety stock review.
It sizes required inventory from daily usage, lead time, and safety stock, then expresses on-hand inventory as protected and unprotected days of supply.

Formula used

Yard inventory turns cycle stock = yard inventory turns daily usage × yard inventory turns lead time
Required yard inventory turns inventory = cycle stock + yard inventory turns safety stock

Inputs explained

Yard inventory turns daily usage: Use recent consumption, demand history, service usage, production schedule, or MRP issue rate.
Yard inventory turns lead time: Enter supplier, internal replenishment, repair, transit, or planning lead time.
Yard inventory turns safety stock: Add buffer for demand variation, supplier risk, quality holds, downtime, or service-level requirements.

How to use the result

Use it when setting reorder points for a grade of scrap, evaluating whether current piles cover the supplier lead time, or sizing safety stock for a volatile feed.
It assumes steady daily usage and a fixed lead time — real scrap inflows and processing rates swing, so treat the days-of-supply figure as a planning baseline, not a guarantee against a supply shock.

Current U.S. benchmarks

The producer price index for steel mill products stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. Quotes priced off last quarter's material cost miss this move.
U.S. iron and steel imports ran $2.1B in May 2026 (Census International Trade). The U.S. ran a trade deficit of $0.4B in the category that month. Import volumes are the pressure gauge behind tariff and reshoring decisions.

Common questions

How do you calculate protected days of supply? Take on-hand inventory and divide by daily usage after accounting for safety stock through the lead-time factor. With 1200 pieces on hand, 85 used per day, and the safety-stock factor applied, the result is about 12.83 protected days of supply.
What is the difference between protected and unprotected days? Unprotected days is simply inventory divided by daily usage — here 1200 ÷ 85 = 14.12 days. Protected days, 12.83 here, discounts that figure for safety stock and lead-time risk, giving a more conservative reorder trigger.
What is a good inventory turns figure for a scrap yard? It depends on feed volatility and storage cost. Faster turns free up cash and yard space but raise stockout risk; slower turns buffer supply gaps. Aim for enough protected days to cover your supplier lead time plus a margin — roughly 13 days here gives a solid reorder cushion.
How do daily usage and lead time affect required inventory? Required inventory is cycle stock — daily usage times lead time — plus safety stock. Higher usage or longer lead time both raise the inventory you must hold to avoid starving the line, which is why volatile feeds need fatter buffers.
Why size safety stock separately? Cycle stock covers expected demand over the lead time; safety stock absorbs the variability around it. Without that buffer, any spike in processing or delay in inbound scrap pushes you below the line and idles equipment.

Last reviewed 2026-05-12.