I don't know whether the casing is used for high-temperature and high-pressure pipelines or containers, or corrosion-resistant media or steel bars.
If internal and external sealing of waterproof casing is required, the casing shall be turned over with a width of 100, and the casing shall be fully welded with the main pipeline. Generally speaking, full welding is necessary for different practical purposes.
Welded steel pipe refers to the steel pipe with joints on the surface after the steel strip or steel plate is bent and deformed into a circle or a square, and the blank used for welding steel pipe is steel plate or steel strip.
Extended data;
Classification of welding methods
According to different welding methods, it can be divided into arc welded pipe, high-frequency or low-frequency resistance welded pipe, gas welded pipe, furnace welded pipe and Bundy pipe.
Welded steel pipe: used for oil drilling and machinery manufacturing.
Furnace welded pipe: can be used as water gas pipeline, etc. Large diameter straight welded pipe is used for high pressure oil and gas transportation. Spiral welded pipe is used for oil and gas transportation, pipe piles, piers, etc.
Classification by weld shape
It can be divided into straight welded pipe and spiral welded pipe.
Straight welded pipe
Simple production process, high production efficiency, low cost and rapid development.
spiral welded pipe
Generally, the strength is higher than that of straight welded pipe. Welded pipes with larger diameters can be produced from narrow blanks, and welded pipes with different diameters can also be produced from blanks with the same width. However, compared with the straight seam pipe with the same length, the weld length increases by 30~ 100%, and the production speed is lower. Therefore, straight seam welding is mostly used for welded pipes with smaller diameter, and spiral welding is mostly used for welded pipes with larger diameter.
Spiral seam welded steel pipes are divided into automatic submerged arc welding steel pipes and high frequency welded steel pipes.
1, spiral seam automatic submerged arc welding steel pipe is divided into class A pipe and class B pipe according to the pressure of conveying medium. Class A pipes are generally welded by ordinary carbon steel Q235 and Q235F and ordinary low-alloy structural steel 16Mn, while Class B pipes are welded by Q235, Q235F and Q 195, which are used as low-pressure fluid conveying pipes.
2. Spiral seam high-frequency welded steel pipes There is no uniform product standard for spiral seam high-frequency welded steel pipes, and ordinary carbon steels such as Q235 and Q235F are generally used.
Reference source; Baidu encyclopedia-welded steel pipe