Welcome to the Carl M. Cummings Manufacturing Company (CMC). Our roots go back to the 1920s, when we were part of TRW. In 1960, TRW spun off its valve manufacturing division, and CMC continued manufacturing valves with the same technology in Southern California. A subsidiary of Maven Engineering, CMC is dedicated to quality and reliability. Our valves are used in locomotive, marine and industrial engines around the world.
To ensure the highest reliability and life span of its valves, CMC uses a unique process whereby the valve head and stem are flash welded. This reduces the possibility of cracking or breaking, and separates our valves from those of our competitors. By using a computer controlled flash welder we can accurately control every phase of the heating and upset/forging phase of the welding operation. In addition, we use Fiber Optics to accurately measure the temperature of the tip during the heating process, ensuring optimum quality in the manufacturing process.
Most valves are made by a process of pushing material through a die which interrupts the original grain flow of the material. This weakens the valve head and makes it more susceptible to surface corrosion.
At CMC, we understand that superior grain flow provides the strongest valve heads available. Our steel is heated by electrical resistance between two contacts and forced through the contacts by a hydraulic ram until enough volume is "upset" to make the pre-form. The pre-form is then passed immediately to the forge. Forging refines the grain structure and improves physical properties of the metal, such as strength, ductility and toughness.
CMC stamps all of its valves on the stem with identification that enables us to trace the material certification, heat treat certification, process and inspection reports for that valve. CMC also warrants all of its valves to be free of material defects and for workmanship for a period of three years.