Processing and forming process of steel elbow
1. Die forging. For socket welded and threaded tees, crosses, elbows, and other small pipe fittings, the shape of which is more complex and should be manufactured by a die forging process, the die forging blank should be a rolled section such as bar, thick-walled pipe or plate. When using steel ingots as raw materials, the steel ingots should be pre-rolled into strips or used as die forging blanks after forging to eliminate segregation, porosity, and other defects of the steel ingots. After heating, the blank is placed in a forging die, and the pressure causes the metal to flow. and fill the die cavity; flashing occurs after blank forging, and the remaining flashing material needs to be flushed out to complete all forging work.
2. Free forging. Pipe fittings of special shape or not suitable for die forging can be manufactured by the free forging process, and the general shape of pipe fittings should be free forged, such as tee branch pipe should be forged.
3. Cutting. For some tubular fittings, such as double socket joints, movable joints, etc., can be directly processed with rods or thick-walled pipes. During the processing, the fiber flow direction of the metal material should be roughly parallel to the axial direction of the pipe. For tee, crosses, elbows, and pipe fittings are not allowed to be directly cut from bars.
Methods to prevent the aging of steel elbows
There are many types of steel elbows, and there are also many used environments and contact materials. The length of the pipe life mainly depends on its anti-aging ability. Due to the influence of materials, the anti-aging effect of some pipes may not be obvious. This method can realize the anti-aging effect of the pipe. Anti-aging:
1. During the laying process, it is very important to overcome the axial deformation caused by the seasonal temperature difference and to control the thermal expansion.
2. When connecting the hot-melt electric welded pipe to the metal pipe and the cement pressure pipe, it should be firmly attached to the bend. In order to avoid the change of axial force due to the temperature change of the material, thus affecting the sealing performance, the serpentine laying of the hot-melt electric melting pipe is within the allowable range of the plan to meet the needs of the temperature change of the pipeline.
3. The blue ribbon can be extruded with a blue tube or a black tube, the latter usually has better anti-ultraviolet and anti-aging properties, a protective cover is also recommended for public use, and the tube should be protected from direct sunlight during transportation, and storage, and placed on site The time should be very short.
Therefore, users should also try to prevent the pipeline from aging when using steel elbows, such as avoiding sunlight and wrapping the pipeline with anti-corrosion tape to protect the service life of the pipeline.