Under the action of thermal stress, because the initial temperature of the surface layer is lower than that of the heart and the shrinkage is greater than that of the heart, because the final cooling volume shrinkage of the heart cannot be carried out freely, the surface layer is compressed and the heart is pulled. That is, under the action of thermal stress, the surface of the workpiece is finally compressed and the center is pulled. This phenomenon is affected by factors such as cooling rate, material composition and heat treatment process. The faster the cooling rate, the higher the carbon content and alloy composition the greater the uneven plastic deformation caused by thermal stress during cooling, and the greater the final residual stress. On the other hand, due to the change of microstructure during heat treatment, i.e. the transformation from austenite to martensite, the increase of specific volume will be accompanied by the expansion of workpiece volume, and each part of workpiece will undergo phase transformation successively, which is just opposite to the thermal stress. The microstructure stress is related to the cooling rate, shape and chemical composition of the workpiece in the martensitic transformation zone.What is the purpose of flat steelSt. Louis ,However, compared with plastics, these pipes,St. Louis 12Cr1MoV alloy pipe,St. Louis 45 seamless pipe manufacturer, like other metals, remain stable and will not be affected by high temperature.Alloy pipe is a very important way and type of seamless steel pipe. Its use is relatively common. It is widely used in various engineering projects, house construction and building decoration. Its fracture will always be found in the production, manufacturing and key marketing of alloy pipe, That is, many stages of production and processing are not done well. Another is that the seasoning is not enough and the proportion of chemical molecules is wrong. There are all reasons.Silvertham,The utility model has the advantages that the axial force of the roll is small, the axial movement is small, the working inclined plane is not required, the pass occupies a small length of the roll body and more passes can be matched under the condition of a certain length of the roll body.Greatly reduce the environmental pollution caused by abrasion, damage and blanking, and increase the labor cost of material cleaningDetermined by the shape, the section modulus, moment of inertia and corresponding strength of I-beam are obviously better than those of ordinary I-beam with the same single weight. When used in metal structures with different requirements, pressure load and eccentric load. Compared with ordinary I-beam, it can greatly improve the bearing capacity and save metal by % ~ %.

At the same height light I-beam has narrower legs, thinner waist and lighter weight than ordinary I-beam. No. - is large I-beam, and No. - is medium I-beam. Imported I-beam shall be marked with actual specifications, dimensions and relevant standards.Galvanized pipes shall be stored in dustproof to keep clean and new . As a professional manufacturer of galvanized pipe, we have produced galvanized pipe products for many years. Welcome friends who need to buy.Alloy tube is widely used in our daily life, which provides us with great assistance. So what industries are alloy tubes applied to? Let&#;s follow the steps of all manufacturers and have a look together:Quality Assurance,Aiming at the connective tissue and texture produced in stainless steel plate Position and other crystal defects are generally removed by heat treatment processes such as quenching or quenching. The effect of quenching is to optimize the crystal, eliminate structural defects, reduce strength, improve plastic deformation, and also conducive to cold drawing. In the production and manufacture of cold drawn alloy pipe, quenching machinery and equipment cannot be lacked. Therefore, the formulation of appropriate annealing process is a necessary condition to ensure that the alloy pipe mechanism meets the standard and the commodity does not crack. If the manufacturer in order to better one sidedness, reduce the product cost and reduce the quenching process, it will eventually lead to bad harm to the product quality.Mixed Scabs are distributed periodically, and the situation after casting and rolling is significant through edge flame peeling crack inspection or billet scratch flame removal. Peak crack

All the cracks occur at -mm away from the edge below the alloy pipe, and the macroeconomic orientation is vertical to the cold rolling orientation, showing a 'high mountain' shape.quality standard,→ wide flange and large lateral stiffness. Strong bending resistance. It has iron zinc alloy layer and compact combination, which shows unique corrosion resistance in marine salt spray atmosphere and industrial atmosphere; The defects can be removed by grinding with sand wheel, but the remaining wall thickness must be within the allowable standard.St. Louis , and the power is large, generally about KW,St. Louis How much is muhdpe alloy tube, which is similar to the plate shearing and bending machine. The general control process is complex, and PLC control is mostly used.The utility model has the advantages that the axial force of the roll is small, the axial movement is small, the working inclined plane is not required the pass occupies a small length of the roll body, and more passes can be matched under the condition of a certain length of the roll body.Methods of exerting efficiency in application of C-section steel