Skip To Content

Chrome Moly/Alloy Steel Valves F11/F22/F5/91

November 2, 2022

Modification on chrome-molybdenum valves is a mainstay at Reliant Valve. We modify both forged and cast chrome-moly steel valves for services that include high-temperature high-pressure steam, delayed coking, H-oil, and hydrocracking. Chrome-moly alloys are known for their resistance to both corrosion and erosion even in high-temperature service.

Modifications we do include end connection changes, gear mounting pads, and trim changes to higher alloys like Alloy 418 and Ascoly 615, When welded, chrome forms carbides within the grain, that anchors the structure even when exposed to high temperature. Chrome additionally adds a significant increase in the hardening ability of the alloy which increases as-welded strength. The purpose of Molybdenum in the alloy is to increase the creep strength. Creep is the plastic flow of a material under constant load or stresses over prolonged periods of time. This precipitation is credited with giving the greatest resistance to creep on chrome-moly steel. Here in Houston, we use several local heat treating companies to do the Post-Weld Heat Treat (PWHT) procedures on all our welded chrome steel valves.