Slots, not holes improve flow through safety screens

Following a test programme associated with an oil tool application, Lee Products is now able to offer custom designed safety screens with rectangular slots as an option instead of round holes.

Tests revealed that Hi-Bar safety screens with rectangular slots, as opposed to circular holes, provided significantly improved flow control. In the tests, two screens, one with 100 micron slots and one with 100 micron circular holes (with both screens having the same open area), were subjected to a flow test while introducing glass beads to simulate contamination. As the screens became clogged with the spherical particles, the results confirmed that the screen with the rectangular slots experienced a 50 percent less pressure drop compared to the screen with the holes.

Typical applications for this type of safety screen will include oil tool production where the likelihood of spherical particles (such as sand) could potentially lead to traditional types of safety screens clogging more easily than those with rectangular slots. Depending on size and material, they can withstand pressure differentials up to 7,500 psid, without rupture.          

The screens are manufactured in 17-4PH stainless steel and are available in UNF and metric threaded boss mount versions and flange mount styles with hole sizes ranging from 75 to 500 microns.

Flange mount screens are also available in brass and PEEK (PolyEtherEtherKetone). Custom designs are also available for more specific application requirements.