Precautions for operation safety of pipe bending machine at different stages
Automatic pipe bending machine is a multi-step programming function, which can also realize automatic operation, which can greatly help to improve production efficiency. Because the hydraulic pipe bending machine adopts steel plate welding structure, the stress can be eliminated during vibration. In addition, the hydraulic pipe bending machines are high-quality imported sealing rings, so they are relatively stable and reliable. The main working mode of most pipe bending machines is the upper piston press. Its driving force has obvious characteristics, which is closely related to the die production process of pipe bending machines. However, it is undeniable that the production safety of the pipe bending machine is higher. The safety matters needing attention in normal use include the following:
The working feature of the full-automatic pipe bending machine is to form pressure through two parallel working hydraulic cylinders. This pressure is vertically downward, and the pressure can drive the die of the bending beam to bend. The typical bending process of the upper bending beam has several stages and links, including downward movement, static state, decompression, return, etc
1： Downward movement
The downward fast closing movement of ordinary pipe bending machine is generally free falling type, that is, the movement is generated by the self weight of the pipe bending machine itself; However, this is not the case for the manufacture of the die of the NC pipe bending machine, but the rodless cavity of the hydraulic cylinder is used to generate pressure, so the fast forward speed can reach 250mm / s, which is more suitable for the production of dies with greater strength.
The fast forward movement starts from the top dead center and ends after a short brake, for example, bending the plate for a certain distance, which can be adjusted according to different mold manufacturing requirements.
2： Static state
The full-automatic pipe bending machine is the top dead center of the upper bending beam in the static position. This state is to prevent uncontrolled downward movement and reduce safety risk.
The decompression of the rodless cavity or the beginning after the pressure holding time when reaching the bottom dead center can further improve the accuracy of the workpiece. Both pressure maintaining and pressure reducing can be commanded and controlled by proportional directional valve. The operation cycle time shall be customized according to the needs. When decompression is required, it can be shortened as much as possible, but the decompression curve shall not be too steep and as stable as possible.
4： Return trip
This involves a large return speed, which mainly depends on the flow of the pump and the pressure bearing area of the rod cavity of the hydraulic cylinder. In general, the closer to the fast speed, the higher the return efficiency. The backhaul also requires synchronization.
5： Stamping and bending
The next stage is stamping and bending, which is not only a key link in the die production of the pipe bending machine, but also the latter link. The stamping speed is limited by the oil supply of the oil pump, but also by the manual intervention regulated by the proportional valve and the directional valve.