Duplex strainers can be used in a versatile manner to filter coarse and fine particles. They are suitable for many liquid system applications. The main advantage of this design is that the two filter chamber construction allowing continuous operation without any shut down for cleaning the component, unlike Y-Type or Mono In Line Type, which must be isolated from the process for maintenance. Other advantages of the DUPLEX - strainers are the large filtration area, which provides a high filtration capacity and low pressure drop, as well as quick and easy access for cleaning.
The change-over between online and standby is achieved by utilising the integral valve system, controlled by a single lever.
The DUPLEX strainer is a single housing assembly with an opposing Inlet- and Outlet flange. Each housing assembly comprises 2 identical filter chambers bolted to a central ball valve diverter chamber. By operation of a single lever, the flow can be diverted from one filter chamber to the second filter chamber without any need of flow interruption. This enables the operator to clean either basket without any requirement to take the system off-line.

Housed in each filter chamber is basket strainer made of a perforated plate, optionally covered with a wire-cloth consisting of various materials and mesh widths. The medium to be filtered flows through the basket from the inside to the outside, hence the contaminants will remain within the strainer basket upon removal from the chamber.