Steel pipe is different from stainless steel pipe fittings. First, the production of steel pipe. Only after a certain price and treatment, it can become stainless steel pipe fittings. Ordinary stainless steel pipe fittings should be subjected to a hydrostatic test to check their pressure resistance and quality. If there is no leakage, wetting or swelling under the specified pressure, some steel pipes should be subjected to rolled edge test, flaring test, flattening test, etc. According to the standard or the buyer’s requirements.
Official classification of standard steel pipe: Steel pipe is divided into seamless steel pipe and welded steel pipe (seamed). According to the cross-sectional shape can be divided into round and shaped pipes. Round steel pipe is widely used, but there are also some shaped steel pipes, such as square, rectangular, semi-circular, hexagonal, equilateral triangle and octagonal.
People often say seamless steel pipe 3360 seamless steel pipe is made of ingot or solid billet through perforation, and then hot rolled, cold rolled or cold drawn. The specifications of seamless stainless steel pipe are expressed in terms of outer diameter wall thickness in millimeters. Seamless steel pipe is divided into hot-rolled seamless steel pipe and cold-rolled seamless steel pipe. There are stainless steel pipe fittings and stainless steel elbows in the back; the following is an introduction to the processing method of stainless steel pipe fittings.
Stainless steel pipe fittings
Stainless steel pipe fittings have six processing methods.
- Forging method: the end or part of the tube is stamped and stretched with a forging press to reduce the outer diameter. Commonly used forging presses are rotary, linkage and roller type.
- Roller method: The core is placed inside the stainless steel pipe fittings tube, and the outer side is pushed and pressed with a roller for rounding the edges.
- Stamping method: In the punching machine with a conical core to expand the end of the tube to the desired size and shape.
- Bending and forming method: There are three commonly used methods, one called stretching method, one called stamping method, and the third called rolling method. There are 3-4 rollers, two fixed rollers, an adjusting roller, adjust the fixed roller spacing, so that the finished pipe fittings are bent.
- Rolling method: generally without a mandrel, for thick-walled tube inside the rounded edge.
- Expansion method: stainless steel pipe fittings of the tube into the rubber, with a punch to compress the upper part, so that the tube bulge molding; another method is hydraulic expansion, filled with liquid in the middle of the tube, using the pressure of the liquid to expand the tube into the desired shape. This method is mainly used to produce corrugated pipes.