Main disadvantages of side horizontal cold heading machine

The die arrangement of cold heading forming machine has two forms: one is vertical arrangement, and the overall structure of the machine tool is horizontal; One is horizontal arrangement, and the overall structure of the machine tool is horizontal. The side horizontal multi station cold heading machine is easy to operate and adjust. Workers can operate standing without bending, and can sit and observe the operation of the machine tool. It is more comfortable - the design concept of the side horizontal cold heading machine seems to focus on this advantage. Compared with its series of disadvantages, this advantage is insignificant.

The main disadvantages of the side horizontal cold heading machine are:

1. The bed structure is asymmetric from top to bottom, left to right, which causes complex elastic deformation and poor overall rigidity.

2. The axial component of the upsetting resistance of each station is distributed on the vertical plane, and its resultant force deviates from the center line of the machine tool, that is, from the center of the connecting rod pin, producing a huge torque on the slider. This torque almost all acts on the slider guide rail, producing a great destructive force on the guide rail. How destructive is it? For example, for a cold upsetting machine with a nominal pressure of 1200 kN, the resultant force of the upsetting resistance can offset the centerline of the machine tool by up to 5 cm (when there is a station without a workpiece, the offset may be greater), and the torque acting on the guide rail is equal to 60 kN · m. If the length of the slider is 1.5 meters, this moment is equivalent to pressing a 4 ton weight on one end of the slider and lifting it with a force of 40 kN (equivalent to 4 tons) on the other end. It goes without saying that the slider and guide rail will have severe uneven wear, and the accuracy of the machine tool can be imagined.

3. Due to structural reasons, the slider guide must be raised, which further aggravates the friction between the slider and the guide.

4. In order to improve the friction conditions between the sliding block and the guide rail, the designer has to lengthen the sliding block, which increases the weight of the sliding block in vain, leading to the reduction of the stability of the whole machine.

5. The ejection mechanism cannot be unfolded on the same plane (longitudinal vertical plane) as the main transmission mechanism, which cannot achieve a compact design. As a result, the structure is complex and huge.

6. The clamp transmission mechanism has the same disadvantage; The complex structure of the clamp box is not commensurate with the uncomplicated functions it realizes.

7. When the workpiece gripped by the clamp is rotated and lowered, the workpiece is easily shaken and thrown off due to the influence of its own weight, especially the longer workpiece.

8. When the clamp (or scissors) of the upper station drops, the workpiece will fall down and may be pressed on the lower station to break the mold and clamp.

9. The height is too large, which blocks the workers' sight and worsens the working environment of the workshop.

10. It is difficult to assemble and disassemble the mold and lift it. From the middle and late 1960s to the 1970s and 1980s, and even the early 1990s, side horizontal cold heading machines became popular in China and gradually formed a series. However, due to the above "top ten crimes", the lateral horizontal cold heading machine finally cannot escape the fate of being eliminated.