Asking for advice on a pipe diameter standard issue
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There is a domestic engineering project, and the owner requires that OD159 steel pipes be used instead of API 6" steel pipes. I don't think so. Does API have OD159 steel pipes? And if not, then the flange of the heavy valve bought abroad will definitely not be usable, right? Is there any way?
The 6" pipe is OD168 and can be replaced by OD159 pipe. Those valve flanges can be used. Because the outer diameter of the pipe is 9mm smaller, then the pipe hole of the flange is only 9mm larger than the outer diameter of the pipe OD, and each side is 4.5mm. Welds can be used to fill this gap.
It can be used, but it is very irregular! It’s like the Chinese dyeing their hair yellow! Haha, it’s best to process the pipe flange neck! It will be better!
It should work, but please note that the flange on the pipe used should be an American standard flange so that it can be connected to the valve.
Let’s talk about this issue separately: 1. The 159 outer diameter is an inherited series, referring to the HG/T20553 II size series, while the outer diameter size of API 150 is 168 (DN150/6"), which is the corresponding outer diameter size description of sh3405/HGT20553 I series/ASME B36.10M (round). Strictly speaking, these two sizes cannot be used universally. Not to mention the welding of steel pipes and flanges, the butt jointing of steel pipes and steel pipes is not allowed. 2. It is impossible to buy 168-caliber steel pipes in the country. They are everywhere. If you can't buy it, it's a matter of purchasing ability and purchasing channels. This post was last edited by Austenitic Stainless Steel on 2009-3-26 15:11 ]
The metric flange of HG20592 is divided into A series and B series in the European system. One end of the A series flange is connected to the metric flange, and the other end can be connected to the British pipe, which can solve the problem.； If the imperial flange is connected to the metric pipe, only the non-standard flange diagram can be produced.
It should be noted that among the standard HG flanges of the Ministry of Chemical Industry, there are two size standards, namely A series and B series, so whether it is a European or American series, you need to pay attention to it. In addition, you can buy the corresponding A or B series in China.
168 tubes are sold everywhere. Why should we change them? Is it to save materials? If the pressure is high, it is best not to change it. If it really needs to be changed, a good welder should be able to do it.
Flanges should be universal, 168 and 159 both have a nominal diameter of 150, just like 114 and 108 have a nominal diameter of 100.