ERW pipes means Electric Resistance Welded Pipes. A plate rolled to become a pipe and welded using Electric Resistance Welding process. Usully for for high diameter. (cheapest process avaiable)
Welded Tube and Pipe Manufacturing Processes
Steel strip in coil, which has been slit into the required width from wide strip, is shaped by a series of forming rolls into a multiple length shell. The longitudinal edges are continously joined by high frequency resistance/induction welding.
UOE is a method used for production of longitudinally welded large diameter pipes. Longitudinal edges of steel plates are first beveled using carbide milling equipment. Beveled plates are then formed into a U shape using a U-press and subsequently into an O shape using an O-press.
Spiral welded pipe production by submerged arc method is based on using tandem welding technique for joining inside and outside coil edges, which have been trimmed and beveled by carbide milling for high quality weld structure.
LSAW (Longitudinally Submerged Arc Welded Steel pipes) in leaflets plate as raw material, the steel plate in the mold or molding machine pressure (volume) into using double-sided submerged arc welding and flaring from production.
Typical ERW Pipe Manufacturing Process
Our manufacturing process generally involves the following stages in a step by step procedure.
Slitting
HR Coils are slitted to pre-determined widths for each and every size of pipes
Uncoiling, End Shearing And Welding
The slitted coil is uncoiled at the entry of ERW mill and the ends are sheared and welded one after another. This results in a single endless strip.
Round forming
Forming
The slitted coils are initially formed into U shape and after that into a cylindrical shape with open edges utilizing a series of forming rolls.
Welding
Welding
In this stage, the open edges are heated to the forging temperature through high-frequency, low-voltage, high current and press welded by forge rolls making perfect and strong but weld without filler materials.
View ERW pipes range
De beading
In this stage, the weld flash on top and inside (if required) is trimmed out using the carbide tools.
Seam Annealing
Seam Annealing
If required, the welding portion and heat affected zone is put to normalizing and then are cooled down in a air cooling bed.
Sizing
After water quenching, slight reduction is applied to pipes with sizing rolls. This results in producing desired accurate outside diameter.
Cutting
In cutting stage, the pipes are cut to required lengths by flying cut off disc/saw cutter.
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.
