NDS Drilling Supply

We offer a 3 X 4 centrifugal pump chromoly fluid end rebuild kit that is hardened. This kit includes hardened casing, casing gasket, hardened impeller, shaft sleeve, mechanical seal and a hardened wear plate.  The hardness on these parts is around 60 Rockwell C.

Chromoly steel is actually alloy steel grade 4130. The “30” at the end of the grade number designates that it has approximately 0.30% carbon by weight. The added Chromium and Molybdenum help to give the steel different properties from its mild steel counterpart, AISI 1030, even though they have the same percentage of carbon.

One of the most important characteristics of chromoly is its ability to be case hardened by carburization of the surface.

This rebuild kit includes steel with added Chromium and Molybdenum that super hardens the steel and it is heat-treated as well. This rebuild kit is far superior to only heat treated kits.  The hardness of Chromoly equals that of sand.  This Chromoly rebuild kit is available on NDS’s Online Store.