Steel pipes can be divided into two categories according to the production method, one is seamless steel pipes, the other is welded steel pipes, and welded steel pipes are straight seam welded pipes. The welded steel pipe can be further divided into high frequency welded pipe (ERW) and double-sided submerged arc welded pipe according to the welding method.
First of all, let's focus on the high-frequency welded pipe (ERW):
The diameter of the high-frequency welded pipe is usually relatively small, and there is no need to pass the welding wire, so the possibility of cracking during expansion is small.
From the point of view of welding speed, for small outer diameter, such as less than 1 inch, the maximum speed can reach 200 m/min.
There are usually two ways of crimping, one is welding, the other is fusion welding, the former has less impact on the steel pipe. High-frequency welding is the first one to take.
Welding the welded pipe from the processing point of view is mainly to bend the steel plate into a cylinder, and then the welding method is simple and efficient.
The double-sided submerged arc welded pipe needs to use welding wire. It is wound into a tube with a complex welding seam that is much longer than that of a straight seam pipe, and the production efficiency will be much lower, but it may be stronger in terms of strength and pressure resistance. It also has other advantages, such as being well automated. Secondly, based on the relatively strong performance of the two aspects, the welding quality of the final product is higher. On the one hand heat exchange and on the other hand protection properties.
The process based on high frequency welded pipe is relatively simple, so relatively speaking, the production efficiency of high frequency welded pipe is higher, but based on the continuous development of double-sided submerged arc welded pipe, its production efficiency is also further improved.
All in all, both welding methods have their own advantages and disadvantages. The advantages of high-frequency welded pipes are that the cracking possibility is small, the welding speed is fast, the welding forming method is simple, and the production efficiency is high. The main advantages of double-sided submerged arc welded pipes are the realization of automation and high welding quality. As for which welding method should be selected in practice, it needs to be analyzed according to the specific situation.
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