ERW Pipe Production Line and Machine Unit

ERW pipe machine unit, ERW pipe production line

The ERW steel pipe/tube production line is the world's first non-destructive testing technology, with advanced forming technology, high-power welding, full-featured, double-weld heat treatment and full-tube heat treatment equipment, as well as a computerized logistics tracking system throughout the process. The integrated medium diameter straight seam welded pipe production equipment is one of the most advanced welded pipe production lines in the world. The main equipment is provided by the world's most advanced straight seam welded pipe equipment manufacturers such as German SMS and MEER, with an annual output of 300,000 tons of line pipes. Straight seam welded pipe products such as erw casing, structural pipe (round pipe, rectangular pipe).

ERW steel pipe machine is a special equipment for production of straight seam welded tube used in metallurgy, construction, transportation, machinery, vehicles and other industries. It uses cold rolled and hot rolled strip as raw material to produce the required specifications of round, square and rectangle tubes through cold roll forming and high frequency welding. It adopts “W” Forming process in the forming process with advantages of making the force more reasonable and the deformation of the material of each rack of the unit is more perfect. 

ERW steel pipe & tube making machine, the process is unwinding the steel coil and make the head and tail of the coil butt-welded in the strips preparation section. Then the strips fed into accumulator and pulled out of the accumulator at a constant speed passed through the unit. Next, the strip is formed into an open tube in the forming unit. After that, it is welded to a straight welded tube by solid-state high-frequency welding method, then to removal of external burrs and water cooling.

ERW pipe mill work flow: 

Uncoiling → shearing and end welding →  material cage → forming → welding → cleaning → cooling → sizing → flying saw cutting → run out table → pipe collecting → packing

Raw material characteristics:

·Pure steel, stable chemical composition, stable performance of steel grade;
·High precision of coil size, good shape control and good surface quality of coil.

Online detection technology:

·Ultrasonic board detection: detect layered defects and longitudinal long defects, and configure defect tracking paint spraying device to ensure 100% detection, tracking and removal of sheet defects.
·On-line weld ultrasonic flaw detection: Weld longitudinal and longitudinal defect detection, heat-affected layer detection and internal burr height control, mainly used for production process control.
·On-line flattening test: take samples for flattening tests at 0° and 90° of the weld and the pressure direction to ensure the basic performance requirements of the weld.
·Hydraulic test: Provide compactness guarantee for the base material and weld of each steel pipe.
·Off-line ultrasonic flaw detection of welds: magnetic particle flaw detection of pipe ends and groove surfaces, manual ultrasonic flaw detection of pipe ends and finished product size inspection.

ERW pipe manufacturing process:
Converter steelmaking → out-of-furnace refining → continuous casting → hot rolling → uncoiling → strip steel flattening → head cutting → butt welding → spiral strip looper → edge washing → strip ultrasonic inspection → forming → high frequency welding → online welding Ultrasonic flaw detection → online weld heat treatment → air cooling, water cooling → sizing → flying saw segmentation (flattening test) → pipe end chamfering → hydraulic test → weld ultrasonic flaw detection → pipe end flaw detection → appearance size inspection → length measurement Heavy → marking → coating → packaging → leaving factory

ERW steel pipe has the characteristics of relatively simple process and rapid continuous production, and has a wide range of applications in civil construction, petrochemical, light industry and other sectors.
It is mostly used to transport low-pressure fluid or make various engineering components and light industrial products.

ERW steel pipe is based on the principle of electromagnetic induction and the skin effect, proximity effect and eddy current heating effect of the AC charge in the conductor, so that the steel at the edge of the weld is locally heated to a molten state, and the butt weld is extruded by the roller to achieve crystal indirection. so as to achieve the purpose of welding seam welding.

ERW steel pipe is a kind of induction welding. It does not require welding seam filler, no welding spatter, narrow welding heat affected zone, beautiful welding shape, and good welding mechanical properties. Therefore, it is widely used in the production of steel pipes.