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Credibility ,All these facilities are also supported by a service center, which tailor makes the coils to customer- requirements by slitting & cutting and by delivering sheets/ coils to customer specifications.
Electric Resistance Welded (ERW)
->Solid phase butt weld, was produced using resistance heating & high pressure to make the longitudinal weld (ERW),
->Nowadays Most pipe mills now use high frequency induction heating (HFI) for better control and consistency. However, the product is still often referred to as ERW pipe, even though the weld may have been produced by the HFI process.
->The defects that can occur in ERW/HFI pipe are those associated with strip production, such as laminations and defects at the narrow weld line.
->Lack of fusion due to insufficient heat and pressure is the principal defect, although hook cracks can also form due to realignment of non metallic inclusions at the weld interface. Because the weld line is not visible after trimming, and the nature of the solid phase welding process, considerable lengths of weld with poor fusion can be produced if the welding parameters fall outside the set limits.
->In addition, early ERW pipe was subject to pressure reversals, a problem that results in failure in service at a lower stress than that seen in the pre-service pressure test. This problem is caused by crack growth during the pressure test hold period, which in the case of early ERW pipe was due to a combination of low weld line toughness and lack of fusion defects.
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Yaang Pipe Industry Co., Ltd. is an international supplier of piping solutions for flange, butt welding fittings, socket welding fittings and threaded fittings. Our products are widely used in different industrial fields, including oil and gas, chemical industry, petrochemical industry, power plant, pulp and paper industry, environmental and water conservancy engineering, engineering projects, etc.