1. What is injection molding:
The so-called injection molding is that the plastic material in the barrel of the injection molding machine undergoes external heating and the shear heat generated by the rotation of the screw plasticizes the resin material into a melt, and then injects the melt into a melt with a certain pressure by applying a certain pressure. The article produced after cooling and shaping in the cavity of the shape is injection molding.
Second, the process of injection molding, that is, the cycle of injection molding:
mode locking
sit in
glue injection
Hold pressure
Melting + Cooling
push out
Mold
Retire
Three, the three basic elements of injection molding:
Machines—including injection molding machines and auxiliary machines.
mold
Material
4. Five elements of injection molding process:
1. Temperature:
A.
Temperature: For the hydraulic machine, it is the heat energy generated by the friction of the hydraulic oil during the non-stop operation of the machine. It is controlled by the cooling water. When starting the machine, make sure that the oil temperature is around 45°C. If the oil temperature is too high or too low will affect the transmission of pressure.
B.
Material temperature: the temperature of the gun barrel. This temperature should be set according to the shape and function of the material and product. If there is a file, set it according to the file.
C.
Mold temperature: This temperature is also an important parameter. Its level has a great influence on the performance of the product. Therefore, the function and structure of the product must be considered when setting, as well as the material and cycle.
2. Speed:
A.
The speed setting of mold opening and closing is generally based on the principle of slow-fast-slow. This setting mainly considers the machine, mold and cycle.
B. Ejection setting: It can be set according to the structure of the product. For complex structures, it is best to eject some at a slow speed and then quickly demould to shorten the cycle.
C. Shooting speed: set according to the size and structure of the product. If the structure is complex and the wall is thinner, it can be fast. If the structure is simple and the wall thickness can be slow, it should be set from slow to fast according to the performance of the material.
3. Pressure:
A.
Injection pressure: According to the size of the product, the thickness of the wall, from low to high, other factors are considered during debugging.
B.
Holding pressure: The holding pressure is mainly to ensure the shape of the product and stabilize the size, and its setting should also be set according to the structure and shape of the product.
C.
Low pressure protection pressure: This pressure is mainly for the protection of the mold, so that the damage of the mold can be minimized.
D.
Clamping force: It refers to the force required for the mold to close the mold and raise the high pressure. Some machines can adjust the clamping force, while others cannot.
4. Time:
A.
Injection time: This time setting must be longer than the actual time, and it can also play the role of injection protection. The set value of the injection timing is about 0.2 seconds larger than the actual value. When setting, the pressure, speed, temperature match.
B.
Low-voltage protection time: This time is in the manual state, first set the time to 2 seconds, and then add about 0.02 seconds to input according to the actual time.
C.
Cooling time: This time is generally set according to the size and thickness of the product, but the melting time should not be longer than the cooling time, as long as the product can be fully shaped.
D.
Pressure holding time: This time is the time to cool the gate before the melt flows back under the pressure of holding pressure in order to ensure the size of the product after the injection is completed. It can be set according to the size of the gate.
5. Location:
A.
The position of mold opening and closing can be set according to the speed of mold opening and closing. The key is to set the starting position of low pressure protection, that is, the starting position of low pressure should be the point that is most likely to protect the mold without affecting the cycle, and the ending position should be The position where the front and rear molds of the mold touch during slow mold clamping.
B.
Ejection position: This position can meet the complete demoulding of the product. First, set it in increments from small to large. Note that the retract position must be set to "0" when loading the mold, otherwise the mold will be easily damaged.
C.
Melt glue position: Calculate the amount of material according to the size of the product and the size of the screw, and then set the corresponding position.
D.
The VP position should be found from large to small, that is, the Short-Short method to find the VP position (that is, the VP switching point).
In short: These five elements complement each other during debugging, and must be connected to each other to set up debugging.
Post time: May-10-2023