Special-shaped seamless steel pipe is a general term for seamless steel pipes with other cross-sectional shapes other than round pipes. According to the shape and size of the steel pipe section, it can be divided into equal-wall thickness special-shaped seamless steel pipe (code D), unequal wall thickness special-shaped seamless steel pipe (code BD), variable diameter special-shaped seamless steel pipe (code BJ). Shaped seamless steel pipes are widely used in various structural parts, tools and mechanical parts. Compared with the round tube, the special-shaped tube generally has a larger moment of inertia and section modulus, and has a larger bending and torsion resistance, which can greatly reduce the structural weight and save steel.
Shaped tubes are more economical. Including non-circular cross-sectional profile, constant wall thickness, variable wall thickness, variable diameter and wall thickness along the length direction, symmetrical and asymmetric cross-section, etc. Such as square, rectangle, cone, trapezoid, spiral, etc. The special-shaped steel pipe can better adapt to the particularity of the conditions of use, save metal and improve the labor productivity of parts manufacturing. It is widely used in aviation, automobile, shipbuilding, mining machinery, agricultural machinery, construction, textile and boiler manufacturing. The methods of producing special-shaped pipes include cold drawing, electric welding, extrusion, hot rolling, etc. Among them, the cold drawing method has been widely used.
According to the cross-sectional characteristics, special-shaped pipes can be divided into three categories: equal-wall special-shaped pipes, different-wall special-shaped pipes and variable-section pipes.
Steel pipe special-shaped pipe can be divided into oval special-shaped steel pipe, triangular special-shaped steel pipe, hexagonal special-shaped steel pipe, diamond-shaped special-shaped steel pipe, octagonal special-shaped steel pipe, semicircular special-shaped steel circle, unequal hexagonal special-shaped steel pipe, etc.Among them, the square tube is the most widely used special-shaped tube.
Square and rectangular pipe is a name for square pipe and rectangular pipe, that is, steel pipes with equal and unequal side lengths. It is made of strip steel that has been processed and rolled. Generally, the strip is unpacked, flattened, coiled, welded to form a round tube, and then rolled into a square tube from the round tube and then cut to the required length.
According to the production process, the square tube is divided into: hot-rolled seamless square tube, cold-drawn seamless square tube, extruded seamless square tube, and welded square tube.
Among them, the welded square tube is divided into
1. According to the process - arc welded square tube, resistance welded square tube (high frequency, low frequency), gas welded square tube, furnace welded square tube
2. According to the welding seam - straight seam welded square tube, spiral welded square tube.
The theoretical weight calculation method of seamless moment management: (side length + side length) × 2 × wall thickness × 0.00785 × length;
Theoretical weight calculation method of seamless square tube: side length × 4 × wall thickness × 0.00785 × length ·
Shaped tubes are more economical. Including non-circular cross-sectional profile, constant wall thickness, variable wall thickness, variable diameter and wall thickness along the length direction, symmetrical and asymmetric cross-section, etc. Such as square, rectangle, cone, trapezoid, spiral, etc. The special-shaped steel pipe can better adapt to the particularity of the conditions of use, save metal and improve the labor productivity of parts manufacturing. It is widely used in aviation, automobile, shipbuilding, mining machinery, agricultural machinery, construction, textile and boiler manufacturing. The methods of producing special-shaped pipes include cold drawing, electric welding, extrusion, hot rolling, etc. Among them, the cold drawing method has been widely used.
According to the cross-sectional characteristics, special-shaped pipes can be divided into three categories: equal-wall special-shaped pipes, different-wall special-shaped pipes and variable-section pipes.
Steel pipe special-shaped pipe can be divided into oval special-shaped steel pipe, triangular special-shaped steel pipe, hexagonal special-shaped steel pipe, diamond-shaped special-shaped steel pipe, octagonal special-shaped steel pipe, semicircular special-shaped steel circle, unequal hexagonal special-shaped steel pipe, etc.Among them, the square tube is the most widely used special-shaped tube.
Square and rectangular pipe is a name for square pipe and rectangular pipe, that is, steel pipes with equal and unequal side lengths. It is made of strip steel that has been processed and rolled. Generally, the strip is unpacked, flattened, coiled, welded to form a round tube, and then rolled into a square tube from the round tube and then cut to the required length.
According to the production process, the square tube is divided into: hot-rolled seamless square tube, cold-drawn seamless square tube, extruded seamless square tube, and welded square tube.
Among them, the welded square tube is divided into
1. According to the process - arc welded square tube, resistance welded square tube (high frequency, low frequency), gas welded square tube, furnace welded square tube
2. According to the welding seam - straight seam welded square tube, spiral welded square tube.
The theoretical weight calculation method of seamless moment management: (side length + side length) × 2 × wall thickness × 0.00785 × length;
Theoretical weight calculation method of seamless square tube: side length × 4 × wall thickness × 0.00785 × length ·
