The production process can be summarized as follows: pre leveling → finishing → straightening → post leveling. Flat steel / A / B steel with width of -, thickness of -, rectangular section and slightly pure edge. Flat steel can be finished steel, or it can be used as blank for welded pipe and thin slab for laminated thin plate.Its heat sealing effect is remarkable. It can be directly buried immediately, which can not only save resources, but also reduce consumption, but also purify the environment. The transportation of gas can meet the requirements of long-distance transportation, reduce heating equipment meet the requirements of thermal insulation and cold protection unique and convenient installation, it is more convenient to use. It can also be used for the transportation of floor heating and hot springs.Ourense ,Classification by section shapeAfter 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, 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.Loa Janan, Hot stamping. Fix the plan product workpiece or preformed vacancy on the rotating journal, with the wheel working pressure vacancy, radial wheel. After one or several solutions, there can also be a variety of methods for the whole process of hollow thick wall rotating body products. Products manufactured by high-precision processing method have excellent physical properties, specification scope, mold shell and software requirements, which are very simple, very easy to be replaced, and relatively low product cost. The processing time is not long enough, the processing capacity is not high, the total length of processing pipeline is limited, and the size of machinery and equipment is generally short.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.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, 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, 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.
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 weight of hot-rolled H steel structure is reduced by % - % compared with the traditional structure.Interpretation and observation, the I-beam flange should be stressed, that is, the I-beam should be standing rather than lying down. Hot hole breaking cold rolling method. This method is dominated by expansion and expands vertical sliding and skew rolling. The former one is mainly cold rolling by relatively limited mandrel mill, cold rolling by few station mandrel mill, cold rolling by three high limited mandrel mill and cold rolling by fluctuating mandrel mill. In this way, the advantages of high efficiency, low metal material consumption, excellent product quality and excellent automatic control system are more and more widely used. The competitive advantage of the latter one is low cost and short whole process. It is suitable for the processing and manufacturing of CrMoG alloy pipes with large quantities, small types, multi specifications and high precision. Therefore it is widely usedThe specification of pass design I-beam is expressed in cm of waist width. For example, the waist width of No. I-beam is. The types of I-beam include hot-rolled ordinary I-beam, light I-beam and wide parallel leg I-beam (H-beam). The waist width of hot-rolled ordinary I-beam in China is ~, expressed as No. ~ No., and the inclination of inner wall of leg is : The pass system of rolled I-beam includes direct pass system,Ourense How much is cold drawn welded pipe, cross pass system and mixed pass system. In addition, I-beam can also adopt special rolling method.
Frame line crackMarket trend,The production process can be summarized as follows: pre leveling → finishing → straightening → post leveling. Flat steel / A / B steel with width of -, thickness of -, rectangular section and slightly pure edge. Flat steel can be finished steel, or it can be used as blank for welded pipe and thin slab for laminated thin plate. According to the process, it is divided into arc welded pipe, resistance welded pipe (high frequency and low frequency), gas welded pipe and furnace welded pipe. Frame line crackOurense ,Plan scheme : high carbon steel with carbon content exceeding .% and alloy pipe with chromium content not less than % Small longitudinal crackStages needing attention in the production and manufacture of alloy tubes