The processing method of large-diameter steel pipe and expression method of the pipe diameter

Large-diameter steel pipes are widely used in mechanical parts, fluid transportation, construction sites, etc. Large-diameter steel pipes have undergone strict inspections during manufacturing, which has also improved their durability. Large-diameter steel pipes have high dimensional accuracy and smooth surface inside and outside the pipe. After heat treatment, there is no oxide film on the inner and outer surfaces of the steel pipe. Deep processing.

Expression of large diameter steel pipe diameter:

1. For water and gas transmission steel pipes (galvanized or non-galvanized), cast iron pipes, and other pipes, the pipe diameter should be expressed in nominal diameter DN;

2. For seamless steel pipe, welded steel pipe (straight seam or spiral seam), copper pipe, stainless steel pipe, and other pipe materials, the pipe diameter should be expressed by outer diameter × wall thickness;

The processing method of large-diameter steel pipe fittings:

1. The price of large-diameter steel pipe fittings is divided into methods such as forging, stamping, rolling, rolling, bending, and expansion.

2. Bending method of large-diameter steel pipe parts: There are three commonly used methods, one method is called the stretching method, the other method is called the stamping method, and the third method is the roller method. There are 3-4 rollers, two fixed rollers, and one Adjust the roll, adjust the fixed roll distance, and the finished pipe is bent.

3. Stamping method for large-diameter steel pipe fittings: Use a tapered core on the punching machine to expand the pipe end to the required size and shape.

4. Roller method for large-diameter steel pipe parts: place a core in the tube, and push the outer circumference with a roller for round-edge processing.

5. Large-diameter steel pipe fittings forging method: use a swage forging machine to stretch the end or part of the pipe to reduce the outer diameter. Commonly used swage forging machines include rotary, connecting rod, and roller types.

6. Rolling method of large-diameter steel pipe parts: Generally, no mandrel is used, and it is suitable for the inner round edge of thick-walled pipes.

7. Bulging method of large-diameter steel pipe fittings: one is to place rubber in the pipe, and compress it with a punch above to make the pipe protrude; Into the required shape, most of the production of bellows is using this method.