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The malleability of forgings is usually carried out in the hot state, and the malleability of forgings is the process of shaping and deforming the metal when it is subjected to pressure processing in the hot state. Forgings generally consider the two indexes of metal shaping and deformation resistance to the malleability of forgings.   Then the factors affecting the forgability of the first is the composition of the metal, pure metal is better than alloy, low carbon steel is better than high carbon steel, low carbon steel alloy steel is better than high carbon high alloy steel; The malleability is generally impaired by harmful impurity elements. There is the use of metal forging organization, single organization is better than want to organization; As cast, columnar structure, coarse grain structure, segregation at grain boundaries, or co-crystallization structure will make the forging ability worse. Finally, the processing conditions of the forging plant should also be considered: 1, deformation temperature: generally with the increase of deformation temperature, the malleability of the metal can be improved; When the temperature is close to the melting point, overburning will be caused, and the malleability will be sharply reduced. 2, deformation speed: on the one hand, with the increase of deformation speed, the recovery and recrystallization process is too late, and the work hardening phenomenon can not be eliminated in time, so that the molding is reduced, the deformation resistance is increased, and the malleability is worse. On the other hand, with the increase of deformation speed, the thermal effect is produced, which is the increase of the metal shape, the deformation resistance is reduced, and is conducive to improving the malleability. 3, stress state: the more the number of tensile stress components, the better the forging material shape; The greater the number of compressive stress components, the lower the plastic requirements of the material.

Hot forging is forging above the recrystallization temperature of the metal. Increasing the temperature can improve the plasticity of the metal, is conducive to improving the internal quality of the workpiece, so that it is not easy to crack. The high temperature can also reduce the deformation resistance of the metal and reduce the tonnage of the required forging machinery. However, the hot forging process is many, the workpiece accuracy is poor, the surface is not smooth, and the forging is easy to produce oxidation, decarburization and burning damage. When the workpiece is large and thick, the material strength is high, and the plasticity is low (such as the rolling bending of the extra-thick plate, the drawing length of the high carbon steel rod, etc.), the hot forging is used. When the metal (such as lead, tin, zinc, copper, aluminum, etc.) has enough plasticity and a small amount of deformation (such as in most stamping processes), or when the total amount of deformation is large and the forging process used (such as extrusion, radial forging, etc.) is conducive to the plastic deformation of the metal, hot forging is often not used, and cold forging is used. In order to complete as much forging work as possible with one heating, the temperature interval between the initial forging temperature and the final forging temperature of hot forging should be as large as possible. However, excessive initial forging temperature will cause excessive growth of metal grains and overheat phenomenon, which will reduce the quality of forging parts. When the temperature is close to the melting point of the metal, the intergranular low melting point material will melt and intergranular oxidation, resulting in overfiring. Burned blanks tend to crumble during forging. Generally used hot forging temperature is: carbon steel 800 ~ 1250℃; Alloy structural steel 850 ~ 1150℃; High speed steel 900 ~ 1100℃; Commonly used aluminum alloy 380 ~ 500℃; Titanium alloy 850 ~ 1000℃; Brass 700 ~ 900℃.   Cold forging is forging at lower than the metal recrystallization temperature, usually referred to as cold forging mainly refers to forging at room temperature, and forging at higher than room temperature, but not more than the recrystallization temperature is called warm forging. The precision of warm forging is high, the surface is smooth and the deformation resistance is small. The workpiece formed by cold forging at room temperature has high shape and size accuracy, smooth surface, fewer processing procedures, and is convenient for automatic production. Many cold forging and cold stamping parts can be directly used as parts or products, and no longer need to be cut. However, in cold forging, due to the low plasticity of the metal, it is easy to crack during deformation, and the deformation resistance is large, and large tonnage forging machinery is required.

1, according to chemical (HG) industry standards: Integral flange (IF), threaded flange (Th), flat welded flange (PL), butt welded flange with neck (WN), flat welded flange with neck (SO), socket welded flange (SW), butt welded ring loose flange (PJ/SE), flat welded ring loose flange (PJ/RJ), lining flange cover (BL (S)), flange cover (BL).   2, according to petrochemical (SH) industry standards: threaded flange (PT), butt welded flange (WN), flat welded flange (SO), socket welded flange (SW), loose sleeve flange (LJ), flange cover (not note)!!   3, according to mechanical (JB) industry standards: whole flange, butt welded flange, plate flat welded flange, butt welded ring plate loose sleeve flange, flat welded ring plate loose sleeve flange, flanging ring plate loose sleeve flange, flange!!   4, according to the national (GB) standard points: whole flange, threaded flange, butt welded flange, with neck flat welded flange, with neck socket welding flange, butt welded ring with neck loose sleeve flange, plate flat welded flange, butt welded ring plate loose sleeve flange, flat welded ring plate loose sleeve flange, flanging ring plate loose sleeve flange, flange cover!

1, pipeline failure, easy to disassemble detection. 2, connect the pipeline and keep the pipeline good sealing performance; 3, if a certain section of the pipeline problems, easy to replace a section of the pipeline;