The processing technology has a great influence on the performance and production cost of HDPE blow molding products. During the processing, the control of processing temperature, main engine speed and parison thickness is particularly important.
Therefore, according to the equipment conditions of the blow molding machine, the process parameters should be reasonably set and adjusted, the control of extrusion blow molding process parameters should be strengthened, and the process operation should be standardized to obtain high-quality HDPE blow molding container products.
1. Structure of HDPE fully automatic blow molding machine
The fully automatic blow molding machine is mainly composed of a frame, a storage head, a feeder, an extruder, a mold, a blowing device, a cooling device, etc.
The fully automatic blow molding machine is mainly suitable for the processing and molding of various plastic blow molding products of HDPE.
2. The HDPE blow molding process mainly consists of 5 steps
① The plastic parison is extruded by the die head, and its thickness is controlled by the wall thickness adjustment system.
② The mold rises and closes, so that the mold tightens and cuts off the parison.
③The mold descends, the air nozzle is inserted into the mold cavity, and the parison is blown toward the cold wall of the mold cavity to form and cool the parison, and a certain pressure is maintained during the cooling period.
④ Open the mold, remove the blown product, and move it to the flash cutting device.
⑤ Trim the flash to get the finished product.
3. Evaluation standards for HDPE fully automatic blow molding process products
Project
Requirements
Wall thickness
Minimum wall thickness
0.6mm
Wall thickness ratio of symmetrical parts
≤1.3:1
Sealing test
Horizontal for 4 hours
No leakage
Drop test
Height 1.5m
No cover popping, no damage
Liquid is water
Suspension test
Residual deformation
≤2mm
Stacking test
3 heights
No collapse
48 hours
Evaluating products according to the requirements of blow molding containers in GB/T 13508-2011 is the evaluation requirement and standard for plastic products.
4. HDPE fully automatic blow molding process parameters
The controllable factors affecting the HDPE fully automatic blow molding machine are mainly processing temperature, blowing time, blowing pressure, mold temperature and main engine speed.
In order to avoid material waste and excessive scraps, the main engine speed and blowing time are generally corresponding. That is, the main engine speed will be adjusted accordingly while adjusting the blowing time. Combined with many years of practical production, it can be concluded that the factors that need to be controlled are blowing pressure, blowing time, mold temperature and processing temperature.
As a professional blow molding machine manufacturer, Yankang has always been committed to the development and production of large hollow blow molding equipment.
