Comparison between laboratory characterization and field performance of steel mud pump liners coated with CM 500L, a tungsten-carbon alloy

A coating of CM 500L (a tungsten-carbon alloy), deposited by a proprietary chemical vapor deposition (CVD) process on a steel mud pump liner, has been developed to give excellent wear resistance against slurry abrasion. The Miller Slurry Abrasivity Test was modified to simulate, as closely as possible, the conditions encountered in the field application. The modified Miller test was used successfully to compare the wear resistance of the coating with the microstructure. This comparison was found to be useful in the development of the coating process, permitting an optimization of the properties of the coating/substrate system for a predictable and acceptable field performance. The modified test procedure is shown to give results which can be used to predict the service life of CM 500L-coated steel mud pump liners with a much greater accuracy than with the conventional procedure