Which filter/strainer unit allows you to clean the element while leaving the system online?

A duplex filter/strainer unit is designed specifically for the purpose of allowing maintenance and cleaning of the filter elements while the system remains online, meaning that the system can continue to operate without interruption during the cleaning process. This is achieved through the use of two filter elements that are connected in parallel. While one filter is in service and filtering the fluid, the other can be taken offline for cleaning or maintenance. Once the maintenance is completed, the flow can be switched to the cleaned filter, allowing the system to operate continuously without downtime.

This design is particularly beneficial in applications where maintaining unbroken service is critical and where the quality of the fluid being processed must be kept very high. Systems with this type of setup ensure operational efficiency and reliability, reducing the risk of contamination and other issues that could arise from pausing the entire system for maintenance. The other options do not provide the capability to clean their elements while allowing the system to continue operating seamlessly, making them less favorable for scenarios requiring constant operation.