Full system of temperature measurement in heat treating: thermocouple types, instrument accuracy, calibration intervals, system accuracy tests (SATs) that compare the furnace control thermocouple with a test probe, and temperature uniformity surveys. Aerospace and automotive suppliers work to AMS 2750 and CQI-9, and auditors usually open the pyrometry records first. A furnace with a lapsed SAT or TUS cannot certify work.
Nadcap auditor spent the whole morning on pyrometry and pulled every SAT on the vacuum furnaces.
Most heat-treat audit findings come from pyrometry records, not from the parts themselves.
Also heard as
- furnace pyrometry
Related terms
TUS
Temperature uniformity survey: a test mapping how evenly a furnace holds temperature across its work zone.
Cert
Shop word for the certificate of heat treatment that states what was done to a lot and the results.
Recipe
Shop word for the stored program of temperatures, times and atmosphere setpoints that runs a furnace cycle.