1、 Production technology of blow molding machine
1. Plastic parison (extrusion of hollow plastic pipe);
2. Close the flap die on the parison, clamp the die and cut off the embryo;
3. Blow the parison to the cold wall of the die cavity, adjust the opening and maintain a certain pressure during cooling;
4. Open the mold and write down the blown parts;
5. Trim the flash to get the finished product.
2、 Basic principle of blow molding machine
The automatic air ring structure on the blow molding machine equipment adopts double tuyeres, in which the air volume of the lower tuyere remains constant, and the circumference of the upper tuyere is divided into several air ducts. Each air duct is composed of air chamber, valve and motor. The motor drives the valve to adjust the opening of the air duct and control the air volume of each air duct.
During the control process, the film thickness signal detected by the thickness measuring probe is transmitted to the computer. The computer compares the thickness signal with the currently set average thickness, calculates according to the thickness deviation and curve change trend, and controls the motor to drive the valve to move. When the film is too thick, the motor moves forward and the air outlet is turned down; On the contrary, when the motor moves in the reverse direction, the air outlet increases, and the cooling speed of each point is adjusted by changing the air volume of each point on the circumference of the air ring, so as to control the transverse thickness deviation of the film within the target range.