Seamless steel pipes are used widely and are usually rolled from ordinary carbon structural steel, low alloy structural steel, etc., which are made of a single piece of metal with no seams on the surface and have good applications. However, seamless steel pipes crack when used due to the influence of original material...

Seamless steel pipes have been widely used in construction, chemical and other industries due to their excellent performance, but cracking will also occur in the application, which will not only cause waste of materials and increase costs but also lead to decreased production efficiency and delays construction period....

Abstract: The steel boiler tubes that burst have been detected and analyzed. The test results show that the temperature and pressure of the blocked parts rise sharply due to poor circulation when the boiler tubes are working, making the part of the tube overheat and the structure grows. The boiler tube cannot withstand...

The appearance of the welding seam of the steel pipes produced by the two welding torches was inspected, and it was found that the last 10 steel pipes produced by the traditional welding torch had the following problems compared with the steel pipes produced by the newly designed welding torch.   (1) Undercut of the...

1.1 A brief introduction to the production line of the steel pipe The welding equipment is mainly composed of a welding power supply (GINNCOLN welding machines and US control systems), control boxes, wire feeding devices, welding head devices, tracking devices and adjustment mechanisms. The welding power supply adopts...

Submerged arc welding is a welding method in which the arc burns under the flux layer. It has the advantages of stable welding quality, high welding production efficiency, no arc light and less smoke and dust. In the process of submerged arc welding, the traditional welding torch uses the contact tip to introduce the energy...

1. Preparation before welding Preparation must be made for submerged arc welding before welding the steel pipe, including groove processing of the weldment, surface cleaning of the part to be welded, assembly of the weldment, cleaning of the surface of the welding wire, and drying of the flux.   ① Groove processing...

1.1 External anticorrosion The external anti-corrosion of water delivery steel pipes mainly includes 3PE coating and hot-melt PE powder. 3PE coating is a relatively complete and better external anti-corrosion process at present, and its anti-corrosion process is shown in Figure 1. Combining the corrosion resistance of...

A spiral welded pipe is the most used water delivery steel pipe. It is made of hot-rolled steel coils after spiral cold processing, and then automatically welded by the inner and outer double-sided submerged arc. The specific production process is shown in figure 1.   1.1 Strength The steel pipe for water delivery...

3. Measures for cracking of welded pipes based on flattening tests 3.1 Improving the welding level Since the level of the welding process will have a direct impact on the flattening test results, which is one of the main reasons for the cracking of the welded pipe, it is necessary to pay attention to the welding process...