Today, Yankang shared with you the operation and maintenance of blow molding machine.
The operator must be familiar with the blow molding machine that he is operating. It is necessary to correctly grasp the characteristics of the screw, the control of heating and cooling, the characteristics of the instrument, the structure and assembly of the control mold of the tractor. In order to correctly grasp the extrusion process conditions and operate the machine correctly.
The first step is the first step in the operation and maintenance of blow molding machine: debugging
How should we debug the blow molding machine?
- Before starting the machine, check whether the temperature control is sensitive, whether the meter is malfunctioning, and whether the cooling waterway is unblocked.
It is usually detected by means of a thermometer or cooling water.
- Heat the screw, barrel, and die of the blow molding machine according to the operating procedure of the blow molding machine. After the temperature rises to the set temperature, it must be kept for another 10 minutes to start up, so that the temperature of each part of the machine tends to be stable.
- Before starting the machine, be sure to tighten the screws and bolts of each part of the die.
The operator must not stand in front of the die before the material is extruded, to prevent the bolt or screw from breaking and causing injury.
- When starting to extrude, the screw speed should be slow, and then gradually speed up to prevent overload and damage the machine at startup.
- When starting the machine, first add a small amount of material and keep the feeding balance.
Pay attention to various values such as torque when feeding. After the material is extruded from the die and pulled onto the traction equipment, the amount of material can be gradually increased until normal extrusion.
- When starting to pull, the shaping dies, and the die should have a certain distance to facilitate traction.
Open the waterway (be careful not to pour the water to the die, otherwise, it will cause the die to be out of the way and cause the material to break or block the mold). The shape of the complex cavity is small and the multi-cavity profile needs to open the cover of the die. . in
After confirming that the extruded material is plasticized normally, the material is drawn onto the tractor through the set traction rope. Shorten the distance between the set table and the die, cover the cover, and start the vacuum pump. When the extrusion speed and the traction speed are basically balanced, the distance between the shaping table and the die is reduced to an ideal value after observing the profile to normal extrusion.
- If it is found that the parison is not formed at the inlet end of the sizing die or the inner rib adheres to the inner cavity surface of the profile, a small tool can be used to poke a small hole in the unformed part of the inner rib of the inlet end of the first section of the sizing die. The small cavity is connected to the atmosphere, and the parison is open when the mold is placed, which facilitates the formation of negative pressure, and causes the parison to be closely attached to the mold wall of the sizing die.
- In the case of blocking the mold (not blocked), the setting table should be moved backward or the traction speed should be increased immediately, or the above two schemes should be implemented at the same time, and then the process adjustment can be used to resume normal production.
If the above scheme is invalid after being blocked, the setting table should be moved back immediately, and the material should be cut along the shaping die, the water vapor of the shaping die should be closed, the traction speed can be reduced, and the profile can be slowly pulled out from the shaping die.
If some of the profiles are broken in the sizing die, the sizing die needs to be removed and the residue removed completely.
- When stopping, it is generally necessary to first add the stop material to extrude the production materials in the machine, then stop and heat the disassembly die for cleaning.
Then the second step of the operation and maintenance of blow molding machine: maintenance of the extrusion die.
How should the extrusion die be maintained?
- Improper loading or unloading or cleaning during maintenance and cleaning is one of the main reasons for damage to the mold. Therefore, the disassembly and cleaning of the mold should be done by a professional.
- The copper part should be used when the die is removed and cleaned.
- the die face (sealing surface) can be cleaned with a fine oil stone or metallographic sandpaper.
- Before the mold is assembled, the flow channel is coated with metallographic sandpaper to a low roughness and coated with a thin layer of silicone ester. To reduce gas and moisture corrosion protection flow paths during long-term storage.
- During the assembly process, all bolts, screw bearing surfaces and threads must be coated with high-temperature grease.
- When disassembling the sizing die, care should be taken to avoid a collision. When installing, install them according to the pattern order number.
- In the daily maintenance of the water tank, it should be ensured that the four sides of the fixed block are properly adjusted to have active space.
Finally, the third step of the operation and maintenance of blow molding machine: the storage of the extrusion die.
How should the extrusion die be stored?
- The mold should be stored in a dry, clean and ventilated warehouse, and it is strictly forbidden to put it in the same stock as the corrosive products;
- After the mold is used, it must be cleaned and reassembled. After the oil seal, it is stored in the warehouse;
- The mold should be stored on a special mold storage rack to ensure safe placement and convenient access.
The above is the operation and maintenance of blow molding machine shared by Yankang.