Alloy Engineering Blog

Vacuum Chamber Fabrication – Key Essentials

Vacuum Chambers are the large containment vessels that hold parts being vacuum heat treated.  The chambers must contain the vacuum and quench cycles inside the furnace during the heat treat cycle. Vacuum Chambers are typically fabricated from carbon and/or stainless steel, with a water jacket for cooling. One or more doors for the loading and unloading of parts into the furnace are hinged to the shell of the Chamber, and typically some type of automated locking ring mechanism keeps the door(s) closed during the heat treat cycle. The look of a Vacuum Chamber is similar to that of an autoclave or a horizontal pressure vessel. 

Fabricating and assembling a Vacuum Furnace can start with ASME code calculations if there is positive pressure in the Chamber, but will always begin with detailed fabrication drawings supplied by Alloy Engineering or the furnace OEM. Fabrication includes plate rolling, fitting of nozzles and flanges, machining of chamber and door flanges, machining of power ports and hinge components, structural support fabrication, welding to ASME standards, and blasting and painting. Non-Destructive Examination typically includes dye-penetrant testing or x-ray, and all finished chambers are subject to helium leak testing and/or hydro testing if code stamped. The ability to post-weld the machine chamber body and door flanges is often critical to maintaining a seal throughout the lifetime of the furnace.


Alloy Engineering provides all of these required vacuum furnace chamber fabrication and machining services in-house.  Check out Four Pros To In-House Manufacturing to learn more. We have 100% control of the schedule, and we control all aspects of quality fabrication and completion. This is one of the reasons why Vacuum Furnace Chamber fabrication is the fastest growing segment of our business, and why Vacuum Furnace OEMs are choosing Alloy Engineering.

Alloy Engineering is a certified ASME Code Section I and Section VIII, Division I fabrication shop. To learn more, contact us here or call us at 440.243.6800.