GB/T 38959-2020Power spinning of high-strength steel - Technological specification (English PDF)

3.1 Arc-shapedroler

The rotary wheel is a rotary wheel whose working profile is composed of an arc [see Figure 1a)].

3.2 Double-tapered surfacesroler

The working profile is composed of two cones and a rotating wheel composed of a transition arc. Its profile is generally composed of three parts, namely the front cone and the rotary wheel

Top fillet and back cone [see Figure 1b)].

The double cone wheel is divided into two types, one without calender angle and the other with calender angle (see Figure 2).

4.2.3.2 Error distance

The offset is suitable for flow spinning. The offset method is axial offset and radial offset (see Figure 9). The radial offset of the rotary wheel should be based on the thickness of the blank wall.

The difference between the spinning gap and the spinning gap is divided by the number of spinning wheels. The axial misalignment of the spinning wheels should be based on the principle that the front cone of the rear wheel does not exceed the front cone of the front wheel.

4.2.3.3 Feed ratio

For shearing and spinning of tapered parts, the feed ratio should be selected in the range of 0.3mm/r~2mm/r; the flow spinning feed ratio of cylindrical parts should be in the range

Choose from 0.5mm/r~1.5mm/r.

4.2.3.4 Spinning angle of attack

The angle of attack of shearing and spinning should be taken from the half-cone angle of the core mold, and the angle of attack of spinning should be determined to ensure that the spinning wheel does not interfere with the blank, tooling, etc. during the spinning process.

Involvement is the principle.

The flow spinning angle of attack is zero, and the axis of the spinning wheel is parallel to the axis of the mandrel.

4.2.4 Confirmation of spinning blank

4.2.4.1 Determination of shear spinning blank

The wall thickness of the spinning blank should be determined by the shear spinning sine law calculation method. Product wall thickness, half cone angle and spinning wool

The relationship between the wall thickness and half cone angle of the blank can refer to equation (2).

4.2.5 Determination of tooling materials and parameters

4.2.5.1 Tooling material selection

Powerful spinning tooling mainly includes spinning mandrel and spinning wheel. The mandrel and wheel materials should have good strength and wear resistance.

Steel is the main product, please refer to Table 6 for specific selection.

4.2.5.2 Cutting and spinning mandrel angle

The angle of the shearing and spinning mandrel should be selected at the lower limit of the design angle of the workpiece.

4.2.5.3 Outer diameter of flow spinning mandrel

The outer diameter of the flow spinning mandrel should be selected at the lower limit of the design size of the inner diameter of the workpiece.

4.2.5.4 Determination of the parameters of the rotary wheel

Shear spinning should adopt an arc rotary wheel (see Figure 1a)], and the radius of the top of the rotary wheel should be selected according to 1 to 3 times the thickness of the blank wall; flow

Spinning should adopt a double-cone roller (see Figure 1b)], and the round corner radius of the top of the roller should be selected according to 0.4~1 times the thickness of the blank wall.

The lead-in angle of the rotary wheel for flow spinning should be selected at 15°~30°, and the lead-out angle is generally not involved in the deformation process, and can be selected at 10°~20° take. If the surface of the workpiece has high requirements for spinning ripples, the roller that finally contacts the workpiece can be a double-cone roller with a calender angle.

The angle is generally 3°~5°, and the length of the calender belt is generally 2mm~6mm.

4.2.5.5 Tooling surface quality

The working surface of the mandrel and the working surface of the rotary wheel should have a higher surface quality, generally Ra takes 0.4µm~1.6µm.

4.2.6 Blank pretreatment

Alloy structural steel should be annealed or tempered at high temperature before spinning. When product performance has special requirements, other heat treatment systems can also be used

The specific methods and performance indicators are determined by the technicians.

4.2.7 Process equipment adjustment

The adjustment of spinning process equipment mainly includes the installation and precision debugging of spinning mandrel and spinning wheel. The runout of the working surface of the spinning mandrel should be guaranteed

The wall thickness of the product is the basic requirement, and the runout of the rotary wheel working surface should not exceed 0.05mm.

4.2.8 Process parameter setting

The process parameter setting is mainly to adjust the spinning gap. The gap adjustment should be carried out when the spindle is stopped and the machine is idling. Can be used

The feeler gauge detects the actual gap, and the gap should be adjusted according to the actual processing conditions to meet the principle of product wall thickness accuracy.

4.3 Spinning

4.3.1 Blank installation

The shearing spinning blank should have a dedicated hoisting position, or a special hoisting tool can be used for lifting; the flowing spinning blank should be fastened with a sling

Afterwards, carry out hoisting.

4.3.2 Adjustment and optimization of process parameters

4.3.2.1 Wall thickness deviation

When the actual wall thickness deviates from the design value, it should be adjusted by changing the spinning gap. When the actual wall thickness is greater than the design wall thickness, it should be reduced

Small spinning gap, on the contrary, the spinning gap should be increased.

4.3.2.2 Diameter deviation of cylindrical parts

When the actual diameter deviates greatly from the design value, the spinning thinning rate can be adjusted. If the actual diameter is larger than the design value, the spinning should be increased to reduce the thickness

On the contrary, the spinning thinning rate should be reduced.

When the deviation between the actual diameter and the design value is small and fine adjustment is required, the feed ratio can be changed to adjust the workpiece diameter. Increase the feed ratio, the workpiece is straight

Diameter decreases; decreases the feed ratio, the workpiece diameter increases.

4.3.2.3 Angle deviation of cone

When the actual angle of shear spinning is larger than the design angle, the spinning gap should be reduced, otherwise, the spinning gap should be increased.

4.3.3 Workpiece disassembly

The shearing and spinning workpiece should be fixed and then disassembled before the tail top exits after the spinning is completed.

The mobile spinning equipment should have a corresponding unloading device to facilitate the disassembly of the workpiece. The workpiece should be fixed during disassembly to prevent the workpiece from falling.

4.4 Spinning treatment

The finished product of spinning should generally be heat treated to remove spinning stress. Common heat treatment methods include recrystallization annealing, stress relief

Fire, tempering, etc.