Aug 3, 2007 · I disagree. The standard refers to the flanges & fittings only, and does not mention weldments at all. The way I see it, the standard refers to the central axis of the fitting (& flange) and therefore as long as pairs of holes are 180degs …

Aug 25, 2009 · An ANSI 150# flange is rated to a pressure of 285 PSI @ a temperature of up to 100°F. that means your design pressure can be a maximum of 285 PSI using 150# flanges, you then multiply this by 1.5 to get 472.5 PSI as the test pressure for a 150 ANSI system.

Jan 20, 2005 · Typically these specifications are identical to ASTM or ANSI standards, although they may not be as updated. So, there may be no difference. Read the ASME specification and it should indicate what it is based on. And check with the flange suppliers to see if the flange in question is dual-rated for both specifications.

Jun 23, 2005 · Can't find data showing pressure capability of Class 150 steel weldneck flange. Not concerned about pressure vs. temp, but, rather pressure vs. bolt torque. I want to use 150lb flanges in an application where system pressure MAY reach 500 psig, normal operating range will be less than 100...

Jan 21, 2011 · One end is an ANSI flange of the proper schedule and rating and material, the other end matches your (pump or filter or tank or hose or eqpt flange or whatever.) Second spool (same length!) matches the ISO/Euto pressure flange, with its oposite end matching your piece of eqpt/tank/hose/etc.

Jan 8, 2010 · The nominal flange “Class” (e.g., Class 125) generally represents the maximum working pressure at the temperature of saturated steam at that pressure. For example, an ANSI/ASME B16.1 Class 125 flange is rated for 125 PSI at 353º F.

Feb 10, 2015 · PN20 is not an original DIN flange - they go PN 2.5, 6, 10, 16, 25, 40, 63 bar rating etc., whereas PN20 is a metricated ASME 150 from the ISO 7005 standard, which was never a good idea in my view. The ASME flanges are converted to PN numbers e.g 20 for 150, 50 for 300 and 110 for 600 to avoid confusion with PN100.

Nov 12, 2009 · The fact that there is a flange capable of higher rating is irrelevant. The flanges should be stamped with the PN rating. E.g, you have a # 150 flange at ambient temp on a line which has a PN 10 flange. This (the PN10 flange) is the lowest rated bit of kit on that line.

Oct 3, 2005 · Also keep in mind, the ANSI flange tables by class has taken into account that different pressure class flanges are constructed differently (eg 300# flanges are much more stout, have more material, than 150# flanges, and different bolting patterns too). "Do not worry about your problems with mathematics, I assure you mine are far greater."

Sep 12, 2003 · A 2 inch 1500 ansi flange was ordered. I rejected it for 2 reasons. 1) The flange was only stamped 900. B16.5 para 4.1.3 states that the applicable rating be stamped on the flange ie: 900, 1500 or 900/1500. 2) The MTR refered only to class 900. The supplier argued that because the two ratings (900 and 1500) were dimensionally the same that it ...