Stainless steel products are widely used in numerous industries and applications, due to their excellent properties and features. Today, here in this piece of article we will be discussing seamless stainless steel pipes and ERW stainless steel pipe and the difference between both these types.
There are a few aspects of differences between ERW stainless steel pipe and seamless stainless steel pipe. ERW pipe, which is short form for electric resistance welding, is used in delivery of liquid, such as fuel, gas and so on, regardless the requirement of pressure, which plays an important role in the conveying pipe all over the world, while seamless pipe is a kind of steel pipe shaping square and rectangle and having no seam around with hollow cross-sections, which is used in conveying liquid but also making structural members and machine parts, due to its surprisingly high anti-bending and anti-torque strength and impossible lightness. All in all, ERW pipe and seamless steel pipe are quite different in use.
Let’s have a glance at those differences between seamless and ERW that can make huge differences for your application and economics of operation.
#1 Raw material
SS Seamless pipes are manufactured out of round steel billets and SS ERW pipes are made out of hot-rolled coils. Although both the raw materials are entirely different, it should be noted that the quality of end product – pipes, entirely depends upon both factors – quality control during the manufacturing process and the initial condition and quality of raw materials. Both these pipes are manufactured in different stainless steel grades but the most common are stainless steel 304 Pipes
#2 Manufacturing process
Round steel billets are heated and pushed over the piercing rod until the hollow shape is achieved. Subsequently, their length and thickness are controlled through extrusion techniques. The manufacturing process is completely different in the case of the production of ERW pipes. The coils are bent axially and the converging edges are welded throughout their length by electric resistance welding.
#3 Welding process
As seamless pipes are extruded, they do not have any sort of joint either in the axial or radial direction. On the other hand, ERW pipes are made out by bending coils along their central axis and hence they are welded throughout their length.
Stainless Steel Seamless Pipes are completely finished in their assembly line and are fabricated up to 26 inches of outer diameter. On the other hand, even the most advanced Steel Company deploying ERW techniques, go only up to 24 inches of outer diameter.
Generally, seamless pipes are used for applications that demand high pressure and ERW pipes are utilized for the services of low and medium pressure areas.
Also, considering the inherent safety features of seamless pipes, they are widely used in applications of oil and gas, refineries, and other chemical industries, where personnel and plant safety needs to be ensured through zero leakage policies. That being said, well-manufactured ERW pipes under strict quality control can also be put into similar services other than the routine ones like water transportation, scaffolding, and fencing.
It is a known fact that the internal finish of ERW pipes is always controlled through good quality control techniques, and hence they are always superior to seamless pipes.