Good performance analysis of cast steel joints

Cast steel joints have good processing performance, complex and diverse architectural style attributes, and the goal is to gradually promote the use of some large-span space tubular truss steel structures, especially in dealing with complex cross-node cast steel joints. It is unique and advantageous, however, Since the total carbon equivalent is high in impurities, in particular, the phosphorus content is difficult to control, and at the same time, the as-cast microstructure is coarse, resulting in steel pipe welding, and the welding technology is highly demanded, mainly to reduce residual stress and prevent welding cracks.

The design of the quenching and quenching medium of the cast steel joint is fully martensitic. Therefore, casting at the quenching cooling rate must be greater than the critical cooling rate of cast steel. Otherwise martensite structure and properties cannot be obtained. However, deformation or cracking of the casting cooling rate is likely to cause excessive. In order to meet the above requirements, appropriate quenching medium cooling should be selected according to the material to be cast, or by other methods (for example, staged cooling, etc.). Between 650 and 400. The isothermal transformation rate of steel undercooled austenite should ensure that this temperature is rapidly cooled during the quenching process. In the following, it is desirable to cool slowly to prevent deformation or cracking. Quenching media are usually fire, water, oil and air. In fractional quenching, austempering, using hot oil, molten metal, molten salt or alkali fusion.

The cast steel joint has stable performance and is widely used in the company to produce precision steel castings. It gives you the following characteristics of cast steel joints: The casting method for producing steel castings has a wide range of materials, which can produce a variety of castings, aluminum processing. Alloys, ferroalloys, and castings of a bowl of alloy. The casting of the brittle alloy material to the poor like ordinary cast iron and other plastics is the only viable forming process. The cast component has a certain degree of dimensional accuracy, and under normal circumstances, the dimensional accuracy of the welded component is higher than that of ordinary forging. The production and processing of low-cost steel castings, energy consumption and material costs are more economical than other metal forming methods. The cast steel joints are 40% to 80% of the total mass of precision castings in normal mechanical equipment, with only 25% to 30% of total equipment cost and manufacturing cost.

Characteristics of cast steel joints

The cast steel joint has the following characteristics compared with the common pipe joint node and the tube plate node:

1) The structural form can be designed according to actual needs, with strong plasticity and beautiful appearance.

2) The cast steel joint is generally solid and only partially hollowed out at the joint, even if it is completely hollow, it is thicker than steel or steel. Therefore, the bearing capacity is high and the deformation resistance is strong.

3) Cast steel joints often replace butt welds with pipe butts, eliminate joint welds of pipe and plate, disperse welds, reduce welding volume and reduce welding stress concentration.

4) The homogeneity is relatively poor.

Application of steel castings: In the above-mentioned steel castings, almost all industrial sectors require steel castings:

1) Power station equipment

2) Railway locomotives and vehicles

3) Construction, construction machinery and other vehicles

4) Mining equipment 5) Forging and metallurgical equipment

6) Aviation and aerospace equipment

7) High pressure container equipment

8) Ship

9) Agricultural machinery is particularly extensive. As for the application of steel castings in various industrial sectors, the conditions may vary greatly depending on the specific conditions of each country.