Key Players Covered Some of the notable companies in the global mud pump market are Mud King Products, Inc. Gardner Denver Pumps, Weatherford, Schlumberger, National Oilwell Varco, China National Petroleum Corporation, Flowserve Corporation, MHWirth, American Block, Herrenknecht Vertical Gmbh, Bentec GmbH Drilling Oilfield Systems, Drillmec Inc, Sun Machinery Company, Shale Pumps, and Dhiraj Rigs.