Sharing China-Made with Global Customers
A major difference between ERW steel pipe billet and hot rolled seamless steel pipe billet is that ERW is manufactured by cold rolling forming of hot rolled strip, while SML is formed by perforating round steel in the hot rolling state. Obviously, the grain size and the weave density of the seamless steel pipe formed in the hot rolling state are quite different from those of the ERW steel pipe billet.
In addition, the dimensional accuracy of ERW steel pipe is much higher. This is due to the fact that seamless pipes are formed by continuous piercing of round bars in a hot rolling mill, while ERW pipes are formed from strips in a cold-rolled state. In contrast, the size control will be much easier for ERW steel pipe also. Because of this, the appearance quality of ERW steel pipe has fewer defects, and the appearance quality is better than that of seamless steel pipe.