The following problems are often encountered when making blow-molded bottles with PET plastic raw materials, so today I will summarize the situations and solutions that are easy to occur in the production process.
Problem 1: The upper part is thick and the lower part is thin. Solution: It is necessary to delay the pre-blowing time or reduce the pre-blowing pressure to reduce the air flow.
Problem 2: There is a situation where the bottom is thick and the top is thin, and the solution: the opposite of the first solution.
Problem 3: The whole bottle looks turbid and has lower transparency. Solution: insufficient cooling.
Problem 4: There are wrinkles in the bottom of the bottle, and the bottom temperature is too high (the cooling at the gate is not good), and the solution: the pre-blowing is too late, the pre-blowing pressure is too low, and the flow is too small.
There will be wrinkles under the bottleneck. Solution: The pre-blowing is too late or the pre-blowing pressure is too low, or the blank cooling here is not good.Problem 6:
There is a magnifying glass at the bottom of the bottle, and there is too much material at the bottom of the bottle. Solution: The pre-blowing is too late and the pre-blowing pressure is too low.Problem 7:
The bottom is white. Solution: The main cause is that the preform is too cold; at the same time it is too stretched; the pre-blowing time is too early or the pre-blowing pressure is too high.Problem 8:
Partial whitening: Excessive stretching. Solution: The temperature here is too low, or the pre-blowing is too early, or the stretching rod is encountered.Problem 9:
The eccentricity of the PET plastic bottle bottom may be related to the preform temperature, stretching, pre-blowing, and high-pressure blowing. Solution: First of all, reduce the temperature of the preform; at the same time, increase the stretching speed; check the gap between the tie rod head and the bottom mold; delay the pre-blowing to reduce the pre-blowing pressure; postpone the high-pressure blowing; check it after processing Whether the preform will still be eccentric.