Spinning process characteristics

        The principle of the metal spinning process is to put the processed metal blank (tube blank) on the mandrel, and the slab is pressed against the end of the mandrel through the tail top, and rotates with the mandrel along with the mandrel, the wheel edge The core mold moves. Under the pressure of the rotary wheel, the metal is machined into the desired hollow rotary structure piece by point using the plasticity of the metal.

       The metal spinning process combines the characteristics of forging, extrusion, drawing, bending, ring rolling, cross rolling and rolling when spinning different shapes of parts, and can be divided into different deformation characteristics of different blanks. Common spinning and strong spinning. In the spinning process, changing the shape of the blank without substantially changing its wall thickness is called ordinary spinning; in the spinning process, both changing the shape of the blank and changing the wall thickness is called strong spinning. Ordinary spinning is limited to processing plastics with good plasticity and thinness. The dimensional accuracy is not easy to control, and the operator is required to have a high technical level. Compared with the ordinary spinning, the strong spinning has no shrinkage deformation during processing because no wrinkles are generated. The machine tool of the spinning machine has a large power, and can also process materials with a large thickness, and the thickness of the workpiece is regularly thinned along the bus bar, which is easier to control.

The metal spinning process has the following main advantages:

      1. The metal deformation condition is good, the spinning is due to the close contact of the rotating wheel with the metal, so the contact area is small, the unit pressure is high, up to 2500~3500MPa, so the spinning is suitable for processing high strength and difficult to deform materials, and The required total deformation force is small, so that the power consumption is greatly reduced. Processing the same size of the workpiece, the tonnage of the spinning machine is only about 1 / 20 of the tonnage of the press.

      2. A wide range of products, according to the capacity of the spinning machine can be made of large-diameter thin-walled pipe, special pipe, variable-section pipe and spherical, hemispherical, elliptical, curved mother-shaped and almost all the turn with step and change thickness Institutional components such as nose cones and casings for rockets, missiles and satellites; submarine infiltration seal rings and torpedo casings, radar mirrors and searchlight enclosures; jet engine fairings and prime mover parts; hydraulic cylinders, compressor casings and cylinders Turbine shafts, nozzles, TV cones, combustion chamber cones and bellows; drums for dryers, mixers and washing machines; shallow pans, hemispherical heads, milk cans and hollow-walled daily necessities.

      3. High material utilization rate and low production cost. Compared with machining, spinning processing can save materials by 20%~50%, up to 80%, and reduce cost by 30%~70%.

      4. The performance of the product is significantly improved. The structure and mechanical properties of the material change after spinning, and the grain size is fine and formed into a fibrous shape. Tensile strength, yield strength and hardness are improved, the strength can be increased by 60% to 90%, and the growth rate is lowered.

      5. The surface roughness of the product is low and the dimensional tolerance is small. The surface roughness of the spin-processed product is generally 3.2 to 1.6 μm, preferably 0.4 to 0.2 μm, and can be rotated to 0.1 μ after repeated spinning. Spinning products may achieve smaller wall thickness tolerances, such as φ300mm, tolerances of 0.05mm, and φ1600mm, tolerances of 0.12mm.

      6. An important feature of metal spinning is the production of a seamless and seamless hollow body, which eliminates the welding-related discontinuities, strength reduction, brittle fracture and tensile stress concentration.

      7. Compared with sheet metal stamping, metal spinning can greatly simplify the equipment used in the process. Some parts that require 6~7 stamping can be manufactured by spinning once. This is the advantage of metal spinning machine. .

      8. The metal spinning method can produce an ultra-wide plate by cutting the spinning cylindrical piece along the direction of the bus bar. In China, the spinning machine capable of spinning φ2m cylindrical parts is not a large equipment. It is easy to make 6m wide plates with such equipment, but it takes a considerable amount to produce 3m wide plates by traditional rolling methods. Rolling mill. In the United States, an ultra-wide plate with a width of 7.5 m and a length of 9 m was produced by a spinning process.

      9. During the spinning process, the spin-on blank is approximately point-by-point deformed. Any defects such as slag inclusions, interlayers, cracks, and blisters are easily exposed. In this way, the spinning process is also attached to the inspection of the product.

      10. Wide source of blanks, hollow stampings, extrusions, castings, welded parts, machined forgings and rolled parts, and round plates can be used as blanks, and can spin titanium, molybdenum, tungsten, tantalum, niobium Metals and their alloys that are difficult to deform.