How do you calculate heat-treat distortion scrap cost?

Multiply scrapped parts by cost per part to get scrapped value, then add the fixed batch cost and containment overhead. Here: 42 x $185 = $7,770, plus $2,400 batch and $950 containment = $11,120 total.

Why include the fixed batch cost if only some parts scrapped?

Running the furnace cycle costs the same whether parts pass or not. When distortion scraps 42 components, the $2,400 of energy, atmosphere, and fixturing for that cycle was spent producing rejects, so it belongs in the loss.

What is the scrap cost per rejected part here?

Total loss divided by parts scrapped: $11,120 / 42 = about $265 per rejected component. That is well above the $185 raw part value because the batch and containment burdens spread across the rejects.

What causes heat-treat distortion in bearings and gears?

Uneven quench severity, poor fixturing or free-stacking, residual stress from machining, and section-thickness variation. The cost model quantifies the damage; reducing it means controlling quench uniformity, press quenching, or fixturing thin rings.

Distortion scrap vs rework, which should I count?

This calculator is for parts scrapped outright. If distorted parts can be straightened or reground, that effort lives in the containment and rework overhead input, not the scrapped-part value, so you avoid double counting.

How do I lower heat-treat distortion scrap cost?

The biggest lever is usually preventing distortion at the source — press or plug quenching for rings, balanced load patterns, and pre-machining stress relief — which shrinks the part count multiplying every other cost in the formula.

Bearings, Gears & Power Transmission calculator

Heat Treat Distortion Scrap Cost Calculator

Heat-treat distortion scrap cost captures the full dollar hit when carburizing or induction hardening warps bearing rings and gears past tolerance and the parts can't be saved. Quality engineers and heat-treat managers use it to size the real loss from a bad batch, justify fixture and quench fixes, and feed cost-of-poor-quality reporting. The number is not just the part value scrapped — it adds the fixed cost of running the furnace batch and the containment, sorting, and rework labor that a distortion event triggers. A 42-part distortion event that looks like roughly $7,800 in parts actually costs $11,120 once batch and containment burdens are counted. That gap is exactly what gets missed when teams quote only scrap piece value.

What this calculator does

Estimate cost exposure from gears, shafts, or bearing components scrapped after heat-treat distortion or hardness nonconformance.
a gear or bearing operation needs to estimate the financial impact of heat-treat distortion scrap on a production lot
It totals the dollars lost to a heat-treat distortion event: scrapped part value plus the fixed furnace batch cost plus containment and rework overhead.

Formula used

Scrapped component value = scrapped components × cost per scrapped component
Total heat-treat distortion scrap cost = scrapped component value + fixed heat-treat batch cost + containment and rework overhead

Inputs explained

Scrapped heat-treated components:
Cost per scrapped component:
Fixed heat-treat batch cost:
Containment and rework overhead:

How to use the result

Use it after a distortion-driven rejection to size the true loss, build a cost-of-poor-quality case, or justify quench, fixture, or process changes.
It treats the batch and containment costs as known fixed inputs; it does not model downstream effects like late shipments, expedite freight, or lost capacity from re-running the batch.

Current U.S. benchmarks

The U.S. has 21,668 machinery manufacturing establishments employing about 1,086,146 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate heat-treat distortion scrap cost? Multiply scrapped parts by cost per part to get scrapped value, then add the fixed batch cost and containment overhead. Here: 42 x $185 = $7,770, plus $2,400 batch and $950 containment = $11,120 total.
Why include the fixed batch cost if only some parts scrapped? Running the furnace cycle costs the same whether parts pass or not. When distortion scraps 42 components, the $2,400 of energy, atmosphere, and fixturing for that cycle was spent producing rejects, so it belongs in the loss.
What is the scrap cost per rejected part here? Total loss divided by parts scrapped: $11,120 / 42 = about $265 per rejected component. That is well above the $185 raw part value because the batch and containment burdens spread across the rejects.
What causes heat-treat distortion in bearings and gears? Uneven quench severity, poor fixturing or free-stacking, residual stress from machining, and section-thickness variation. The cost model quantifies the damage; reducing it means controlling quench uniformity, press quenching, or fixturing thin rings.
Distortion scrap vs rework, which should I count? This calculator is for parts scrapped outright. If distorted parts can be straightened or reground, that effort lives in the containment and rework overhead input, not the scrapped-part value, so you avoid double counting.

Last reviewed 2026-05-12.