Which Is Better Between Seamless vs Welded Pipe?

It is quite natural to get confused between a seamless stainless steel pipe and a welded pipe. While the former is manufactured by the round steel billet through hot and cold rolling without any seam, the latter is manufactured by a flat steel plate, with a welding seam on the pipe body. Today, Sigma Steel Pipes is here with yet another blog that will tell you in detail how these two are different and which one of them is better.

The Major Differences

Let’s differentiate between the two pipes on the basis of a variety of factors such as follows:

• Manufacturing

The API 5L and ASTM Seamless steel pipe adopts a steel ingot or solid tube as raw material through the perforated tube, then can be formed by hot rolled, cold rolled, or cold draw. On the other hand, the API 5L or ASTM welded stainless steel pipe includes LSAW pipe, SSAW pipe, and ERW steel pipe. These pipes are made with steel strips or steel plates. The manufacturing processes first bending the steel plate, then welded into circular, square, and other shapes. Welded steel pipe has the characteristics of high production efficiency, low cost, and saving material. 

• Appearance difference

Seamless steel pipe used steel billet as raw material. The outer surface defects of the billet cannot be eliminated by the hot rolling process, it is only polished after the product is finished. In the process of wall reduction, the defect can only get partially eliminated. A welded stainless steel pipe, on the other hand, is made of the hot rolled coil as raw material, the surface quality of the coil is just the pipe’s surface quality, and easy to control. The surface of the hot rolled coil is high quality.

• Molding processes

Seamless steel pipe can be formed one time in the rolling process, however, welded steel pipes are molded with steel strips or steel plates, through bending and different welding processes.

• Performance and Usage

Seamless steel pipe has better pressure capacity, and strength higher than ERW welded steel pipe. So it is widely applied in high-pressure equipment, thermal, and boiler industries.

Generally, the welding seam of the welded steel pipe is the weak point, and the quality affects overall performance. In general, welded steel pipes can withhold 20% less working pressure than seamless ones. This reliability is the prime factor why people go for seamless steel pipe. As a matter of fact, all industrial pipelines are done with seamless pipes only because the pipes undergo extreme thermal, chemical, and mechanical workloads. Welded pipes are more preferred in aerospace, automobile, and electronics industries where the budget is comparatively low, and so is the work pressure put on the pipes.

• Size

At Sigma Steep Pipes, the original seamless pipe can be 20 inches maximum. Where usually smaller than 16 inches, because of the equipment limits. And if the client would like to purchase seamless steel pipe more than the above sizes, then hot expanding machining shall be used. But usually, this kind of hot expanded seamless steel pipe quality could not compare with the original seamless steel pipe. On the contrary, welded steel pipes don’t have these limitations, and sizes are available from 1-1/2 inches to 100 inches.

When it comes to cost, Sigma Steel Pipes charges decent rates for both pipes. However, it is found that because of the raw material involved, the manufacturing equipment, as well as processes, seamless steel pipe cost, is usually on the higher side as compared to welded steel pipes. Place your order now at https://sigmapipes.com/ and get the most tensile steel pipes from India’s leading wholesale pipe supplier.