SYSTEMS AND METHODS FOR MAKING A MODULAR RAILROAD RETARDER CONTROL SYSTEM

A cartridge assembly for a railroad retarder control system. The cartridge assembly includes a body having a top and a valve base and defining a bore. The bore has first and second bore diameters, and the body defines pilot air passages, an upper air passage, and a lower air passage. A traveling member is positioned within the bore and has first and second traveling diameters corresponding to the first and second bore diameters of the body, respectively. The traveling member is axially moveable within the bore between open and closed positions via pressure differentials within the pilot air passages. The traveling member is closer to the top of the body in the open position than in the closed position. The traveling member has a base seal configured to engage with the valve base in the closed position to prevent air from flowing between the upper and lower air passages.