Duplex Strainers – Staples and Pfeiffer

Duplex strainers are used in lines that continuously run and do not need to be shut down.  The duplex strainer uses a tapered plug design with twin baskets, and are equipped with a diverter handle to switch from one basket to the other.  The basket not in use can be removed and cleaned without interrupting the pipeline flow.  S & P duplex strainers utilized an increased wall thickness, are offered in 150# and 250# class, and have been shock tested to MIL-S-901D.

STAPLES & PFEIFFER, INC was established in 1900 by Lyman Staples and August Pfeiffer and originally located in San Francisco, California.
In January 2009, The Hellan Strainer Company acquired the product line of Staples & Pfeiffer and relocated it to their manufacturing plant in Cleveland, Ohio.


 A limited number of Military Products are shown on this page.   For more information regarding the complete line of Hellan Strainer Military Products, contact a government sales representative.


Model 123 Duplex Basket Strainer, In-Line Flow, Bronze

Military123Duplex Strainers are available in sizes starting at 1″ and can be as large are 8″.  Hellan Duplex Strainers can be supplied in ANSI, DIN or Navy Drilled to MIL-F-20042D flanges.



Simplex Strainer Straight Flow.

Size Operation Flow Technical Drawing
1″ – 8″ Duplex Straight pdficonsmall