API 686 temporary strainers

[shvet]

Dear forummembers

Please comment

4.6.3 For the protection of centrifugal pumps during flushing and for the initial operation of new oil systems, a removable strainer that is made from ASTM Series 300 stainless steel and has an minimum open flow area equal to 150 % of the cross-sectional area of the suction pipe shall be installed in the suction piping of each pump between the pump suction flange and the block valve. The temporary strainer shall be identified by a protruding tab and shall have a mesh size adequate to stop all objects that could damage the pump. The piping arrangement shall permit the removal of the strainer without disturbing the alignment of the pump. The maximum strainer hole size shall be 3 mm (1/8 in.). Cone strainers shall be installed in spool pieces to minimize piping removed.
NOTE Strainer can be cone, basket, or Y-type. For typical ASME and API pumps, a mesh size of 500 is sufficient. For canned, screw, and magnetic drive pumps, a 100 to 200 mesh screen is required.

For typical pumps 30μm, for special pumps 75-150μm? Misprint? May be vice versa - 30μm for special and 75-150μm for typical?

 

[LittleInch]

Suspect a typo.

Should be 50 mesh.

500 would block up very easily with fine debris.

IME you want to install a Y filter body to stop you having to break the pipework... Been there and its very difficult to get everything back aligned.

Oh and make sure you have a DP installed or you can end up with a very large DP once a plastic bag arrives.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[georgeverghese]

Folks at the API seem to be in a mighty hurry these days - there are grossly obvious bugs in API RP 14C in the 2017 edition also.

 

[shvet]

Thank you, gentlemen