Difference between flange sizes SO25 and DN25
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What is the difference between the flange models SO25_150LB and DN25_150LB? What does each one mean? Thank you!
It refers to a flat-face flange with a size of 1 inch and a pressure rating of 150; the other one has a pipe diameter of 1 inch and also a pressure rating of 150
This post was last edited by Dawn Bellows on 2015-9-15 at 15:09. The flange model SO25_150LB indicates that the flange’s specification is DN25; SO– denotes a flange with a neck, but no information is given regarding the type of sealing surface. 150LB refers to the pressure rating of the flange, which is 150 pounds (PN20). The standards that govern this are ASME B16.5, or Sinopec’s standard SH3406-2013, or HG/T20592-2009. In the American system, DN25 in DN25_150LB denotes the nominal diameter of the pipe, while 150LB represents the pressure rating of the pipe, namely 150 pounds (PN20)
The first one specifies a flat welding flange, DN25, 150LB. The second one does not specify the flange type; this information is available in the standards, making it easy to find. For imperial units, one can refer to HG/T20615. For national standards, you can take a look at HG/T20592
I’ve learned it; I roughly understand it now. Thank you!
SO stands for flat welding flange. The ones at the back do not indicate what type of flange they are. All sizes are DN25, and all pressures are CL150
The explanation on the 3rd floor is quite accurate; thumbs up! ! ! ! ! ! ! ! ! ! ! ! !
To be precise, neither HG/T 20592 nor HG/T 20615 uses the designation “DN25_150LB”. Examples of designations for HG/T 20592 (PN series): Flange SO 25-25 FM 20. Examples of designations for HG/T 20615 (class series): Flange SO WN 25-150 FM 20
Such profound knowledge; I’ve learned a lot: lol
Such profound knowledge; I’ve learned a lot: lol
SO means flat welding, but it’s not expressed that way