duplex basket filter

A Duplex Filter consists of 2 separate basket strainer housing connected in a manner that the flow can easily be diverted to either of the strainers. This design is especially for applications that require continuous flow.
While one of the strainers is in use, the other can be stopped for cleaning purpose and vice-versa.
These two housings are connected with a 3-way valve that helps to divert the flow while the strainer to be cleaned drains the fluid through the drain valve.
Basket strainers typically have an open area ratio of 6:1 and sometimes as high as 8:1. This is the ratio of net free area of the screen to pipe area. The area is calculated with a clean basket & as the basket begins to clog, the ratio will drop. As material collects on the basket surface, the available amount of open area is reduced thereby resulting in reduced flow through the strainer and/or exhibiting a higher differential pressure.
Strainer baskets are generally designed to withstand up to 20 PSI differential pressure, however a properly sized strainer will begin with ≤2 PSI differential pressure and be cleaned once the differential pressure increases by 5 PSI because at this point nearly all the basket surface area is covered & the differential pressure will begin to increase.