Furnace Survey

[AeroIndah]

Appreciate if anyone can let me know on the interpretation of Pyromerty AMS 2750.How to perform instrumentation survey and furnace survey.As for the furnace survey, what should be the variation between control TC and Workload sensor/TC.
Planning to purchase Vacuum Furnace for Precipatition hardening,Sress relief and Tempering.
Thank you.

 

[balu1]

The proper procedure in aerospace industry is to get approval from independent, accredited (ISO 900X approved) source.

They install their master TCs (of known accuracy, supposedly high) in your furnace, covering the working space (e.g. 10 TCs for 1 cu.ft. or per some ASTM spec if there is one). If those calibrated TCs show +/-5deg C difference of preset furnace temp (Rollce-Royce Aero Engines requirement for HT furnaces) your furnace temperature field (space) is all right and your TC is all right.

If the TCs measurements are within 10deg C but the furnace TC shows higher or lower temp than calibrated-master TCs, the homogenity of temp field is OK but furnace instrumentation (control) is not.

Regarding checking furnace TC you may have some calibrated TCs for that purpose (see the following site

http://www.watlow.com/literature/specsheets/

files/sensors/richts100.pdf) but those would be production checks only.

The major survey however, in my opinion, should be done by independent specialized company at least once a year.