category：Building materials / date：2024-09-19 00:37:13 / browse：54 / comment：6
Plan scheme : high carbon steel with carbon content exceeding .% and alloy pipe with chromium content not less than %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, the heart is pulled. At the end of cooling, 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,Old horse10 I-beam price, 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, resulting in inconsistent volume growth and structural stress. The final result of the change of tissue stress is the tensile stress on the surface and the compressive stress in the center, shape and chemical composition of the workpiece in the martensitic transformation zone.Old horse,How are seamless tubes made?Plan scheme : for high carbon steel with carbon content of more than .% and high chromium alloy pipe with chromium content of no less than %,Old horseWhich is a good welded pipe manufacturer, the interval is min.Sinjah,When selecting I-beam in structural design, reasonable I-beam shall be selected according to its mechanical properties, chemical properties, weldability and structural size.Difference and application description between H-beam and I-beamI-beam is an economic section high-efficiency profile with more optimized section area distribution and more reasonable strength weight ratio. It is named because its section is the same as the English letter 'H'.
With the development of steel structure buildings, only I-beam is not enough, that is, thickened I-beam, which is easy to lose stability for load-bearing columns. Manganese: it can improve the strength of steel, weaken and eliminate the adverse effects of sulfur, and improve the hardenability of steel. High alloy steel (high manganese steel) with high manganese content has good wear resistance and other physical propertiesThe core of C-section steel is the structural system of braced frame. More than half of such senior managers in China are the former. Unfavorable to earthquake resistance. Hydraulic power, and the power is large, generally about KW, which is similar to the plate shearing and bending machine. The general control process is complex, and PLC control is mostly used.Service first,After the passivation treatment of alloy pipe, it is clearly proposed that water cleaning shall be carried out immediately after the aqueous solution ~ times of water cleaning,Old horse5310 alloy pipe, and then chromic acid closed solution shall be carried out. Chromic acid solution must be carried out h after the subsequent water cleaning of metallographic structure and austenitic alloy pipe. Chromic acid aqueous solution (mass ratio) is % ~ %, the solution temperature is ~ ℃, and the solution time is min. Then dry.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, the heart is pulled. At the end of cooling, because the final cooling volume shrinkage of the heart cannot be carried out freely, 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, 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, resulting in inconsistent volume growth and structural stress. The final result of the change of tissue stress is the tensile stress on the surface and the compressive stress in the center, 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.Generally, there are many passivation methods for alloy tubes, the common ones are high temperature passivation or sodium cyanide passivation.
Metallization: refers to the process of penetrating metal atoms into the surface layer of alloy steel pipe. It is to alloy the surface layer of steel so that the workpiece surface has the characteristics of some alloy steel. Aluminizing, chromizing boronizing, siliconizing and so on are commonly used in production.total cost,Carburizing: carburizing is the process of penetrating carbon atoms into the surface layer of steel. It also makes the low-carbon steel workpiece have the surface layer of high-carbon steel, and then after quenching and low-temperature tempering, the part of the workpiece can maintain the toughness and plasticity of low-carbon steel.It is also divided into general welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe, idler pipe, deep well pump pipe automobile pipe, transformer pipe, electric welding thin-wall pipe, electric welding special-shaped pipe, scaffold pipe and spiral welded pipe.I-beam is a kind of economical section steel with better section mechanical properties. Its characteristics are as follows:Old horse,→ compared with general section steel, it has the advantages of low cost, high precision and small residual stress. It does not need expensive welding materials and weld detection, and saves about % of the manufacturing cost of steel structure.With the development of steel structure buildings, only I-beam is not enough, that is, thickened I-beam, the more serious the disadvantages.
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