The manufacture of electric resistance welded pipe

We next examine the basic steps necessary to produce electric resistance welded (ERW) pipe.

ERW Production Lines

Coil Feed Ramp
Coil Feed Ramp

The coils are removed from storage and placed on the feed ramp (see Figure 4.1). Each coil is fed into the uncoiling unit.

First Forming Section
First Forming Section

The roll transition section receives the product from the first forming section and continues the "rounding-up" process .

Final Forming Pass Section
Final Forming Pass Section

This section of the forming rolls finishes the rounding process and prepares the edges of the strip for welding .

High-Frequency Welder
Automatic High-Frequency Welder

An automatic high-frequency welder heats the edges of the strip to approximately 2600 F at the fusion point location.
Pressure rollers squeeze these heated edges together to form a fusion weld.

In-Process Weld Nondestructive Inspection
Nondestructive Inspection Unit
Nondestructive Inspection Unit

After welding has been completed, it is inspected by independent nondestructive inspection units.

Seam Weld Normalizing
Seam Weld Normalizer

The weld area is then subjected to postweld treatment, as metallur-gically required, to remove residual welding stresses and produce a uniform normalized grain structure.

Sizing Mill
Sizing mill

The pipe passes through a sizing mill to achieve the correct outside diamete.

Cutting the Pipe

The pipe is then cut to the correct length.

End Facing And Bevelling

This is usually stage, where the pipes ends are faced and bevelled by the end facer. All these processes are continuous with automatic arrangements. These plain ended tubes further go for processing as per the customer requirements such as galvanizing, threading, black varnishing and more.

Weled steel pipe specification, Standard and identification

Welded steel pipe (steel pipe manufactured with a weld) is a tubular product made out of flat plates, known as skelp, that are formed, bent and prepared for welding.