Perforated Metal - Exterior Pressure

[Geof]

This is not really a code item, but I'm looking for a rational way of rating a strainer element.

When determining the maximum dP across a strainer element, my company has traditionally used Sect VIII internal pressure calculations with a deduction for "plate efficiency" based on hole pattern. This works great.

The problem - a lot of customers need to install them "inside-out". External pressure calculations using the "plate efficiency" as the thickness renders extremely conservative results, to say the least.

Any ideas?

 

[MJCronin]

Geof....

How about testing a bunch of them and developing your own empirical coefficients based on test results ?

This should be a fairly straight forward test rig.....

 

[Geof]

That would be nice but - small company, no test department. There've been field failures over the years (ours and other's) that have provided enough rules of thumb that we don't usually have a problem. However, it would be nice to have a solid answer to "how much is this rated for?"

As a side note - I've got a collapsed strainer from another company that I measured up. We are supplying replacements with additional stiffening. Apparently, it's not an isolated problem.

Thanks for the input.