Special-shaped seamless steel pipe is a general term for seamless pipes with cross-sectional shapes other than round pipes. Special-shaped seamless steel pipes are widely used in various structural parts, tools and mechanical parts. Compared with round pipes, special-shaped pipes generally have a larger moment of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce the structural weight and save steel.
Special-shaped steel pipes can be divided into oval special-shaped steel pipes, triangular special-shaped steel pipes, hexagonal special-shaped steel pipes, diamond-shaped special-shaped steel pipes, octagonal special-shaped steel pipes, semicircular special-shaped steel rounds, unequal hexagonal special-shaped steel pipes, and five-petal plum-shaped special-shaped steel pipes, Double convex special-shaped steel pipe, double concave special-shaped steel pipe, melon-shaped special-shaped steel pipe, conical special-shaped steel pipe, corrugated special-shaped steel pipe.
Shaped seamless pipe forming method
1. Diameter reduction/expansion forming
The shrinkage forming process of the reducer is to put the tube blank with the same diameter as the large end of the reducer into the forming die, and press along the axial direction of the tube to make the metal move along the cavity and shrink into shape. According to the diameter of the reducer, it can be divided into one-time press forming or multiple press forming. Diameter expansion forming is to use a tube blank that is smaller than the diameter of the large end of the reducer, and use an inner die to expand the diameter along the inner diameter of the tube blank. The diameter expanding process mainly solves the situation that the reducing pipe with a large diameter is not easy to be formed by reducing the diameter. Sometimes, according to the material and product forming needs, the methods of expanding the diameter and reducing the diameter are used in combination. The reducer (large and small head) is a pipe fitting used to reduce the diameter of the dry pipe. The commonly used forming process is reducing diameter pressing, expanding diameter pressing or reducing diameter plus expanding diameter pressing, and stamping forming can also be used for reducing pipes of certain specifications.
2. Stamping
The shape of the die used for stretching is designed with reference to the size of the inner surface of the reducer, and the blanked steel plate is stamped and stretched with the die. In the shrinking or expanding deformation pressing process, according to different materials and changing conditions, it is determined to use cold pressing or hot pressing. Under normal circumstances, try to use cold pressing, but for the case of severe work hardening caused by repeated diameter reduction, the case of thick wall thickness or the material of alloy steel, hot pressing should be used. In addition to using steel pipes as raw materials to produce reducers, some specifications of reducers can also be produced by stamping steel plates.
Tips: Seamless square tubes and seamless rectangular tubes are also special-shaped seamless steel tubes
a500 rectangular tube theoretical weight calculation method: (side length + side length) × 2 × wall thickness × 0.00785 × length;
a500 square tube theoretical weight calculation method: side length x4x wall thickness x0.00785 x length
Special-shaped steel pipes can be divided into oval special-shaped steel pipes, triangular special-shaped steel pipes, hexagonal special-shaped steel pipes, diamond-shaped special-shaped steel pipes, octagonal special-shaped steel pipes, semicircular special-shaped steel rounds, unequal hexagonal special-shaped steel pipes, and five-petal plum-shaped special-shaped steel pipes, Double convex special-shaped steel pipe, double concave special-shaped steel pipe, melon-shaped special-shaped steel pipe, conical special-shaped steel pipe, corrugated special-shaped steel pipe.
Shaped seamless pipe forming method
1. Diameter reduction/expansion forming
The shrinkage forming process of the reducer is to put the tube blank with the same diameter as the large end of the reducer into the forming die, and press along the axial direction of the tube to make the metal move along the cavity and shrink into shape. According to the diameter of the reducer, it can be divided into one-time press forming or multiple press forming. Diameter expansion forming is to use a tube blank that is smaller than the diameter of the large end of the reducer, and use an inner die to expand the diameter along the inner diameter of the tube blank. The diameter expanding process mainly solves the situation that the reducing pipe with a large diameter is not easy to be formed by reducing the diameter. Sometimes, according to the material and product forming needs, the methods of expanding the diameter and reducing the diameter are used in combination. The reducer (large and small head) is a pipe fitting used to reduce the diameter of the dry pipe. The commonly used forming process is reducing diameter pressing, expanding diameter pressing or reducing diameter plus expanding diameter pressing, and stamping forming can also be used for reducing pipes of certain specifications.
2. Stamping
The shape of the die used for stretching is designed with reference to the size of the inner surface of the reducer, and the blanked steel plate is stamped and stretched with the die. In the shrinking or expanding deformation pressing process, according to different materials and changing conditions, it is determined to use cold pressing or hot pressing. Under normal circumstances, try to use cold pressing, but for the case of severe work hardening caused by repeated diameter reduction, the case of thick wall thickness or the material of alloy steel, hot pressing should be used. In addition to using steel pipes as raw materials to produce reducers, some specifications of reducers can also be produced by stamping steel plates.
Tips: Seamless square tubes and seamless rectangular tubes are also special-shaped seamless steel tubes
a500 rectangular tube theoretical weight calculation method: (side length + side length) × 2 × wall thickness × 0.00785 × length;
a500 square tube theoretical weight calculation method: side length x4x wall thickness x0.00785 x length
