Working principle of PET stretch blow molding machine

The PET stretch automatic bottle blowing machine is an automatic intelligent bottle blowing machine. At present, it is mainly a two-step linear bottle blowing machine. The whole bottle blowing process is divided into preheating and bottle blowing molding. The detailed working principle is as follows:

 

1. Whole preform transfer

 

The full-automatic feeding machine will feed the preform to the gripping position. The gripping will lower the preform and enter the heating oven through the transmission chain.

 

2. Preheat

 

The preform enters the infrared lamp oven through the transmission chain for heating. There are two rows of horizontal red line lamps in the infrared oven. The temperature of each lamp can be adjusted by the micro controller PLC. The upper and lower red line lamps have a stable constant temperature, but the height is different. In order to keep the diameter of the bottle unchanged at the bottom of the bottle, it is generally not heated. At the same time, due to the high temperature environment, it is cooled by the dispersion tube in the water cooler. The temperature from the middle of the preform to the bottom of the bottle is controlled by constant temperature. Due to the upward evaporation of the hot gas, the temperature of the bottom of the bottle is relatively low, otherwise it is easy to cause the bottom of the bottle to be too thin and cause the bottom of the bottle to break.

 

3. Blow to bottle

 

The heated preform enters the mold closer for bottle blowing. The hot bottle blank enters into the mold closer, and the bottle blank is sealed. With pre blowing gas, the stretching rod at the bottom stretches the bottle blank upward, pre blowing gas to a certain extent, low-pressure blowing, and high-pressure blowing, the bottle is instantly formed in a short time, and the bottle blowing is completed. Before pre blowing the gas, a cold dryer is usually installed. The gas passes through the filter to filter the water in the air and the oil in the equipment lubrication. The gas is clean and the formed bottle has no oil smell. In addition, in order to increase the heat of the mold and the temperature in the mold, the temperature of the mold will drop rapidly through the water cooler, and the quality and output of the bottle will be guaranteed.

 

4. Recovery of excess gas

 

After one blow, the high pressure and low pressure gas in the blowing bottle will be discharged, which will cause energy waste and increase energy consumption. By installing the recovery gas device, the pre blowing gas and blowing gas will enter the gas storage tank through the one-way valve, which can save 25% of energy consumption.

 

Flow chart of PET bottle blowing machine

 

Pet automatic bottle blowing machine selection principle:

 

1. Choose according to your own products. According to the different specifications of the radius, capacity and production capacity of the bottle, choose different models and the number of mold cavities

 

2. It is recommended to choose the manufacturers with design ability and continuous R & D ability and perfect after-sales service.

 

3. Choose the bottle blowing machine with high cost performance. The price is reasonable and the performance is stable.