What counts as productive cure hours?

Only the hours a released cure schedule was actually running: ramp, dwell and controlled cooldown on a load. Time with the vessel hot between jobs, waiting for tooling or under maintenance is available time, not productive time.

Why block productive hours above available hours?

The productive part of a period cannot exceed the whole. When it does, the two counts usually come from different periods or different vessels, so the page stops rather than publishing a utilization above 100 percent.

How should planned maintenance be treated?

If the vessel is scheduled and staffed during the maintenance, keep those hours in available time and the utilization correctly shows the loss. If the vessel is genuinely off the schedule, remove them from both counts and note the basis.

What is idle autoclave hours used for?

It sizes the empty schedule slots a new or moved load could use. A large idle figure with a full order book points at batching, tooling readiness or scheduling rather than another vessel.

Composites, Fiberglass & Advanced Materials calculator

Autoclave Utilization Calculator

Measure how much of the vessel's available time went to cure schedules you can charge, and compare it with your target. You need productive cure hours and available hours from the same period and vessel.

What this calculator does

Autoclave utilization from productive cure hours and available hours, with the gap to target and idle time.

Formula used

Autoclave utilization = productive cure hours ÷ available autoclave hours × 100
Gap to target = target utilization − autoclave utilization
Idle autoclave hours = MAX(available hours − productive hours, 0)

Inputs explained

Productive Cure Hours: Hours the vessel ran an accepted cure schedule in the period.
Available Autoclave Hours: Scheduled hours the vessel was staffed and available, from the schedule.
Target Utilization: Your utilization target for the vessel, from site standards.

How to use the result

Best suited to monthly capacity review on a shared vessel, justifying a second autoclave or a longer shift.
A half-full vessel counts the same as a full load, so this is time utilization only. Planned maintenance inside available hours lowers the percentage by design.

Current U.S. benchmarks

As of Aug 2026, U.S. manufacturing runs at 75.7% of capacity (Federal Reserve via FRED), down 0.1 points from a year earlier. Enter your own plant's utilization; the national figure is a reference point for how loaded the industry is.
The producer price index for plastic resins and materials stands at 280.569 (BLS, Aug 2026), up 6.6% from a year earlier. Quotes priced off last quarter's material cost miss this move.
Steel mill PPI stands at 381.162 (BLS, Aug 2026), up 23.4% from a year earlier. New factory orders are up 8.5% year over year (Census).

Common questions

What counts as productive cure hours? Only the hours a released cure schedule was actually running: ramp, dwell and controlled cooldown on a load. Time with the vessel hot between jobs, waiting for tooling or under maintenance is available time, not productive time.
Why block productive hours above available hours? The productive part of a period cannot exceed the whole. When it does, the two counts usually come from different periods or different vessels, so the page stops rather than publishing a utilization above 100 percent.
How should planned maintenance be treated? If the vessel is scheduled and staffed during the maintenance, keep those hours in available time and the utilization correctly shows the loss. If the vessel is genuinely off the schedule, remove them from both counts and note the basis.
What is idle autoclave hours used for? It sizes the empty schedule slots a new or moved load could use. A large idle figure with a full order book points at batching, tooling readiness or scheduling rather than another vessel.

Last reviewed 2026-10-01.