For pipes at what degree angles is oblique welding used, and for pipes at what degree angles is elbow cutting employed?
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For pipes at what angle should oblique welds be used, and for what angle should elbows be used for cutting? Which specifications specify this?
I really don’t know the standard for this. Do we need to consider the heat-affected zone from the elbow cutting? If, after cutting, all the bends are within the heat-affected zone, then they can’t be used, right? @boyirensheng
For elbows, carbon steel and alloy steel with a wall thickness of 5 mm or less can use a flat groove; for thicknesses over 5 mm but up to 22 mm, a beveled groove is required. When the thickness exceeds 22 mm, a combined groove is needed. For stainless steel, a flat groove is used when the thickness is 3 mm or less; for thicker sections, a beveled groove is applicable, and when the thickness exceeds 22 mm, a combined groove is required. In practice, most cases involve grooves with thicknesses between 3 mm and 5 mm
Bro Zhao, what does it have to do with the groove? I’m asking you: what angle of bend is possible when cutting a bend, and the pipe needs to have a flat end ； For angles below this value, the tube is cut at an oblique angle.
The angle of the elbow joint shall not be greater than 22.5°
The angles of elbows come in specifications such as 22.5, 45, 60, 90, 180 degrees, etc. For angles of 22.5 degrees or less, multiple straight sections are usually connected at an angle, in a manner similar to a horsehead elbow; however, this approach is not generally used in pressure pipelines, and design considerations must take this into account
The smallest angle that has been seen so far is 15 degrees; generally, it starts at 22.5 degrees
So few people answered! I have this problem too……