How do you calculate fixture capacity for tube forming?

Multiply parts per cycle by available cycles to get gross capacity, then multiply by uptime% and yield%. With 4 units/cycle and 480 cycles you get 1,920 gross; at 90% uptime and 97% yield that lands at 1,676 good units.

What is the difference between gross capacity and good capacity?

Gross capacity (1,920 units here) assumes every cycle runs and every part passes. Good capacity (1,676) subtracts 192 units lost to downtime and about 52 units lost to yield, leaving what you can actually ship.

What is a good uptime for a tube-forming fixture?

Well-run roll-form and end-form stations hold 85-92% uptime once tooling is proven. The 90% default is realistic for a mature job; brand-new tooling often starts in the 70s until clamps and stops settle in.

How much does yield loss cost me here?

At 97% yield the fixture loses roughly 52 units across the shift. Push yield to 99% and you recover most of that; drop to 92% and yield loss more than doubles, which is often the fastest capacity gain available.

Should I count planned setup time in available cycles?

No. Available cycles should already exclude planned changeover and PM. Uptime% then captures unplanned stops during the run, so you are not double-counting downtime.

How do I use this to decide on a second fixture?

If required daily volume exceeds good capacity even at your best realistic uptime and yield, one station cannot hold the schedule and a second fixture or an extra shift is warranted.

Tube, Pipe & Profile Forming calculator

Fixture Capacity Calculator

Fixture Capacity tells a tube- and profile-forming shop how many conforming parts a forming fixture or roll-form station can actually deliver in a shift, not just its theoretical maximum. It multiplies the nest count per cycle by available cycles, then discounts for clamp/spindle uptime and first-pass yield. Process engineers and production planners use it to promise realistic ship dates, size fixturing for a new tube family, and decide whether to add a second fixture before quoting a big run. Because a multi-cavity bend or end-form fixture can look impressive on paper yet bleed 20-30% to downtime and scrap, the 'good capacity' number is the one that matters on the floor.

What this calculator does

Fixture Capacity tells a tube- and profile-forming shop how many conforming parts a forming fixture or roll-form station can actually deliver in a shift, not just its theoretical maximum.
Use it when fixture capacity in tube, pipe and profile forming is being asked to take on more work and you need to know if there is room.
It computes the number of good, conforming formed tubes a single fixture station can produce over a set of cycles after uptime and yield losses.

Formula used

Gross fixture capacity capacity = units per cycle × available cycles
Good capacity = gross capacity × uptime × yield

Inputs explained

Formed tubes per fixture cycle:
Available forming cycles per shift:
Fixture uptime (spindle/clamp availability):
First-pass yield after forming:

How to use the result

Use it when quoting capacity for a tube or profile part, sizing fixtures for a new program, or checking whether one station can hold a delivery schedule.
It treats uptime and yield as flat averages; a fixture that scraps heavily during the first-off setup or degrades as tooling wears will not follow a single steady percentage.

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.

Common questions

How do you calculate fixture capacity for tube forming? Multiply parts per cycle by available cycles to get gross capacity, then multiply by uptime% and yield%. With 4 units/cycle and 480 cycles you get 1,920 gross; at 90% uptime and 97% yield that lands at 1,676 good units.
What is the difference between gross capacity and good capacity? Gross capacity (1,920 units here) assumes every cycle runs and every part passes. Good capacity (1,676) subtracts 192 units lost to downtime and about 52 units lost to yield, leaving what you can actually ship.
What is a good uptime for a tube-forming fixture? Well-run roll-form and end-form stations hold 85-92% uptime once tooling is proven. The 90% default is realistic for a mature job; brand-new tooling often starts in the 70s until clamps and stops settle in.
How much does yield loss cost me here? At 97% yield the fixture loses roughly 52 units across the shift. Push yield to 99% and you recover most of that; drop to 92% and yield loss more than doubles, which is often the fastest capacity gain available.
Should I count planned setup time in available cycles? No. Available cycles should already exclude planned changeover and PM. Uptime% then captures unplanned stops during the run, so you are not double-counting downtime.

Last reviewed 2026-05-12.