How is the quenching process of the straight seam welded pipe carried out?

The surface quenching of straight seam welded pipe usually adopts induction heating or flame heating, and its main technical parameters are surface hardening and effective hardening layer depth. The following introduces the important means of surface hardness testing during heat treatment of straight seam welded pipes:

The shell with a thickness of 0.05mm can be tested with a test force of 0.5-100kg. It has the highest precision and can distinguish small differences in the surface hardness of heat-treated workpieces; in addition, the effective depth of the hardened layer also needs to be tested, so it is necessary to measure the effective depth of the hardened layer.

The main processing method of straight seam welded pipe

Forged steel: A pressure processing method that uses the reciprocating impact force of a forging hammer or the pressure of a press to change the embedded material into the shape and size we need. Extrusion: A processing method in which the steel is placed in a closed extrusion sleeve, and one end is pressurized to extrude the metal from the specified die hole to obtain a finished product with the same shape; it is mainly used for the production of non-ferrous metal steel.

Rolling: A press working method in which a billet is passed through a gap (various shapes) of a pair of rotating rolls, the cross-section of the material being reduced and the length increasing due to the compression of the rolling.

Drawing steel: The rolled metal billet (profiles, products, etc.) is drawn into the section through the die hole, reducing the length and increasing the processing method, mainly for cold working.

Straight seam welded pipes are very suitable for hardness testing of surface hot-worked workpieces and are available in three sizes. Although the surface Rockwell hardness tester is not as accurate as the Vickers hardness tester, it can meet the requirements of quality management and quality inspection in heat treatment plants.

In addition, the straight seam welded pipe has the advantages of simple operation, low price, fast measurement speed, and direct reading of hardness values. Surface Rockwell hardness tester can be used for rapid non-destructive testing after surface heat treatment of straight seam welded pipes. When the surface heat treatment hardening layer of the straight seam welded pipe is thick, the parts can also be used; when the local hardness requirement is high, the local heat treatment can be carried out by means of induction heating; for this straight seam welded pipe, the local heat treatment shall be indicated on the drawing. Location and local hardness values.

The straight seam welded pipe adopts high frequency coil welded pipe, and adopts high frequency coil welded pipe. The steel pipe has strong bearing capacity, good plasticity and easy welding. After various rigorous scientific tests and tests, it is safe and reliable to use and saves investment in pipeline construction. Longitudinal welded pipes are mainly used in water engineering, petrochemical industry, chemical industry, electric power industry, agricultural irrigation, urban construction and so on.

Different from straight seam welded pipes, seamless steel pipes are made of steel ingots or solid billets through perforation to make capillaries, which are then hot rolled, cold rolled or cold drawn. The seamless pipes specifications are expressed in millimeters of outer diameter * wall thickness, and are widely used in the manufacture of structural parts and mechanical parts.

Author
Chase Liu