Screw-in hydraulic cartridge valves were pioneered in the 1970s and quickly adopted by many major manufacturers. Cartridge valves have become popular because they allow quick design of customized hydraulic circuits using a machined manifold block. Manifold blocks can range from two valves to 50 or more and are easily manufactured with little investment using standard equipment and tooling.
The proliferation of manufacturers in the early days led to a variety of cavity configurations often unique to each valve manufacturer. Today, cartridge valve styles fall into three major categories—the common-cavity valve, the floating valve cavity, and the metric-cavity valve, which is prevalent in Europe. Cartridge valves now encompass a vast array of functions with broad flow and pressure capabilities and continue to develop along with ever more affordable and advanced electronic controls.