STANDARD HEADS

[HABER]

CAN WE USE STANDARD F&D HEAD AS A TOP OF ASME TANK WITH NO INTERNAL PRESSURE - DESIGNED FOR FULL VACUUM ONLY?
UG-32(j) SECTION VIII DIV I PROVIDES LIMITATION TO KNUCKLE RADIUS NO LESS THAN 6% OF OUTSIDE DIA, BUT UG-33 DOES NOT MENTION ABOUT IT. WE HAVE ALL REQUIRED TEST REPORTS ATC.FOR THIS HEAD.

 

[JoeTank]

There is nothing wrong with using an F&D head for vacuum conditions. It is done frequently. However you must check it for vacuum conditions per the ASME Code requirements. The weakest portion of a head for vacuum conditions is the dished portion. Therefore, the dished portion is checked for vacuum as a portion of a spherical vessel. Hope this helps.

Steve Braune
Tank Industry Consultants

http://www.tankindustry.com