Because the tube is low intensity, 400 ℃ following is basically no plastic, when the tensile stress exceeds the tensile strength of steel, weld cold cracking occurs.

Iron and steel industry is the basic industry of the national economy, which is the national economic level and an important indicator of overall national strength, the steel industry directly affects the development of the defense industry and its associated buildings, machinery, shipbuilding, automobiles, home appliances and other industries. However, to some extent, steel pipe price will also affect the mobilization of relevant industries a price volatility.

Other countries and ISO stainless steel standards are provided for hot-rolled (forged) steel, in addition to heating pressure processing steel, the general heat treatment delivery (heat treatment requirements need to be specified in the contract).

Aluminum alloy quenching furnace is heated in hood and mobile undercarriage component.

Slab dishing factors and improvement measures mainly in the following areas:

Skew rolling flaring wall-expanding process, extending coefficient of 1. In the event of the main deformation, inevitably be some extra additional deformation.

When hearing of API steel pipe, nearly all of us will feel unfamiliar about it and the reason is simple, that is most of us do not live close to oil well, so, it is usual that we have less knowledge about the API steel pipe.

In recent years, with the surface quality continuous improvement of hot dip galvanized, the coating quality of the galvanized sheet has also been greatly improved.

Precision steel casting technology was originally used in a vertical continuous casting machine, which is an important part of the production of ingots, can greatly save operating costs. Curved new caster caster is improved, since it is possible to further lower the production cost savings, thus playing an increasingly important role.

Post weld heat treatment is to improve the organization and properties of welded joints or eliminate residual stress and heat treatment carried out. Commonly used methods are normalized or normalized and tempered with two stress elimination process.

Pipe welding temperature control techniques: steel for the steel into welded pipe, the multi-channel roll rolling, gradually rolled steel, formed with a circular tube opening gap, the adjustment squeeze roll reduction, make welding seam gap control in 1 ~ 3mm, and weld ends flush. The gap is too large, reducing the proximity effect is caused by lack of eddy heat weld together to produce crystal indirect incomplete fusion or cracking bad.

Structural steel pipe racks typically support pipes, power cables and instrument cable trays in petrochemical, chemical and power plants.