Production Of High Quality Precision Welded Pipe

1 Production of precision welded pipe with small internal burrs: Removing the burr inside the weld is an important aspect of the quality of precision welded pipe products. The removal of the inner burr of the small-diameter welded pipe has always been a technical challenge in the welded pipe manufacturing industry due to space constraints. As a result, selecting an appropriate welding method from the welding technology is a viable solution to the problem. DC electric welding and square wave resistance welding are two methods for welding with small internal burrs. These welding methods are distinguished by uniform heating, smooth welding seams, high quality, and small internal burr formation, typically 0.1 to 0.2 mm.

2 Microbeam plasma method to create high-precision, ultra-thin-walled welded pipe: The wall thickness difference reaches 0.002 to 0.007 millimeters after cold rolling, where the excessively large outer diameter ellipse is effectively eliminated. Ultra-thin-walled welded pipe is welded using the microbeam plasma method. The outer weld is bright and smooth, the inner weld is flat and dense, and the average burr height does not exceed 0.031 to 0.020 millimeters. It has the same structure and properties as seamless tubes after heat treatment, and the advantages of using seamless tubes to create ultra-thin tubes are significantly less advantageous than those of creating ultra-thin tubes by cold rolling after welding.

3 High-strength welded pipe for the automotive industry: The lightweight of automobiles has recently been promoted by the domestic and international automotive industries in order to save energy, and it is urgent to switch out solid parts with high-strength hollow ones. Technically speaking, high-strength welded pipes can be developed to replace seamless pipes in the automotive industry. Japan has developed a series of steel grades, such as C-Ti-B, C-Mn-Nb, and C-Cr-AI-B, and adopted various heat treatment systems in order to develop high-strength welded pipe for the automotive industry, like annealing, quenching and normalizing, tempering, etc. Its standard strength levels are 561 MPa, 637 MPa, 980 MPa, etc., and it is used for high-strength welded pipe in the automotive industry. Butt welded pipe must also have high plasticity, good workability, hardenability, toughness, and fatigue strength in addition to high strength.