The cartridge is the functional component of two-way cartridge valve. Its main body is seat structure, namely the seat-type main stage, differentiating itself from the traditional sliding spool valve structure.
A cartridge normally consists of a spool, a sleeve, a cap, seals and a spring. A cap is used in the cartridge which diameter is between 16 and 32, but not over 40. The spool and the sleeve are coupled in slide. The seal between the bottom of the spool and other components is normally linear sealing. The geometric shape of that bottom is very important, which has several structural options. Cartridge has different area ratios and opening pressure springs to meet various applied requirements.