EN
First, D means the NPS of the pipe. The radius of a 3D elbow is 3 times the NPS of the pipe from which it is made. Likewise, a 5D elbow has a radius of 5 times the NPS of the pipe.
Carbon steel buttweld fittings are manufactured from seamless or welded mild steel pipes, through cutting into appropriate length, heating, forming, etc. It's very weldable to be installed onto piping systems. So you may find it on most piping systems.
Buttweld fittings can keep the strength of the piping system due to continuous metal material.
Cost-saving by using Buttweld fittings instead of threaded or socket weld fittings.
Smooth flow inside piping systems can be guaranteed by using buttweld fittings with matching pipe schedules.
Buttweld carbon steel reducers provide gradual change of pipe diameter.
Manufacturing Standards of Carbon Steel Buttweld Fittings
ASME B16.9, ASME B16.28
MSS SP-43, MSS SP-75
DIN 2605/2615/2616/2617
JUST 17375/17376/17378/17379, ISO
Carbon Steel Buttweld Fittings is made by cold or hot forming. Eg. A Tee is formed by using a hydraulic press to extrude a bypass out of a piece of pipe inside a mould.
First, D means the NPS of the pipe. The radius of a 3D elbow is 3 times the NPS of the pipe from which it is made. Likewise, a 5D elbow has a radius of 5 times the NPS of the pipe.
Well, we have both seamless and welded carbon steel buttweld fittings. It's up to you to buy which one.
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