Plastic products occupy a relatively large proportion of our lives, especially those large and small plastic packaging bottles, which are closely related to our daily lives. Although this kind of container looks very simple, it is very particular about its craftsmanship. Especially in blow moulding PET bottles, we often encounter various blowing problems. Affected the success rate and efficiency of bottle blowing. Based on our more than 20 years of production experience, iBottling has summarized the following solution for your reference.
Or, if you want to directly raise your own technical problems, let us give the best blowing solution, or you can contact us at any time through the form below.
Bottle defect 1:
Poor transparency of PET bottles from bottle blow moulder
- The thermostat is set too high.
- Compressed air contains water 2. Heating time is too long
- The injection PET preform is opaque in and of itself.
- The PET preform’s design isn’t appropriate.
- The inflation rate is far too low
- Take a break.
- Reduce the amount of time it takes to heat up.
- To get rid of the water, use a dryer.
- Improve PET preform quality, select materials, and increase raw material dryness
- Improve the PET preform’s size design
- Reduce the PET preform’s diameter.
Bottle defect 2
The PET bottle made by blow moulder has a pearly luster and is white in color.
- The thermostat is set too low.
- PET preforms with uneven wall thickness
- The thickness of the PET preform is too thick, and the heating and penetration are inadequate.
- Increase heating tempature or decrease the rotational speed.
- Improve the quality of PET preforms
- To raise the surface temperature of the PET preform, reduce the thickness of the PET preform or increase the outer cover of the heating device.
Bottle defect 3
The nozzle is offset at the bottom of the PET bottle made by PET bottle blowing moulder.
- You’re blowing too soon
- The stretch rod isn’t all the way down
- The extension rod is angled away from the bottle axis’s center line.
- The injection density or wall thickness of the PET preform is uneven.
- Inconsistent heating Problem:
- Increase the descending speed of the stretching rod or delay the blowing time.
- Adjust the magnetic pole switch’s position.
- Adjust the stretch rod’s position.
- Improve the quality of PET preforms
- Check for any problems with the rotation of the PET preform or improve the heating conditions.
Bottle defect 4
PET bottles with uneven wall thickness of PET bottle blow molder machine
- The stretch rod is not in the center of the PET preform for several reasons.
- The blowing holes are asymmetrical, with different diameters.
- The stretching or expansion ratios are too small or too low.
- In the heating furnace, the PET preform does not rotate.
- An uneven thickness of the embryonic tube wall or an uneven injection density
- Adjust the stretch rod’s position.
- Adjust the blowing hole’s position and diameter.
- Increase the inflation or stretching ratio.
- Examine the device for rotation.
- Improve the quality of PET preforms
Bottle defect 5
The bottle’s upper portion is too thick when using PET blow moulder machine
- The temperature in the oven’s upper part is too low
- The mold vent is too far away from the upper portion of the oven.
- The stretching ratio is insufficient.
- The upper portion of the bottle’s inflation ratio is too low.
- The speed of the stretching rod is too slow.
- Raise the temperature of the upper heating tubes.
- Adjust the vent’s position.
- Increase the ratio of stretching
- Modify the bottle’s shape.
- Change the stretch rod’s speed.
Bottle defect 6
The bottle’s bottom is far too thin making PET bottle by bottle blower moulder.
- Begin blowing too early
- The bottom temperature is too high
- The PET preform’s bottom is too thin.
- Postpone the start of the blowing time.
- Reduce the temperature at the bottom.
- Increase the thickness of the PET preform’s bottom.
Bottle defect 7
There is an obvious bottle clamping line by bottle moulder.
- An insufficient clamping force
- The time for sealing is too early.
- Mold issue
- The germ tube tooth mouth is not the same size as the mold.
- Raise the clamping pressure and adjust the clamping support rod’s angle (by 5 degrees).
- Return the mold clamping stroke switch to its original position.
- Check the mold’s assembly position, such as whether the guide post is loose or the mold is not tightly pressed, and repair it if necessary.
- Adjust the mold teeth to their proper position.
Bottle defect 8
The material accumulates because the bottom of the bottle or the bottleneck has been rolled up with blow moulder machine.
- The delayed blowing time is excessive;
- There is only one good roll.
- The material accumulation temperature is too low.
- The action’s air pressure is unstable, causing the stretching rod to descend at a slower rate.
- Reduce the descending speed of the stretch rod or shorten the delayed blowing time.
- On one side of the reel bottle, reduce the gas volume.
- Raise the PET preform’s heating temperature
- Add a gas storage tank or shorten the gas supply pipeline to the action gas source.
Bottle defect 9
Stretching and perforating the bottom of the bottle by PET bottle moulder
- Insufficient temperature and no penetration
- Delay stretching time is too long
- The stretch ratio is too large
- The bottom of the PET preform is too thin
- The stretched club head is too sharp
- Warm up
- Shorten the delay stretching time
- Reduce stretch ratio
- Improve the bottom design of PET preform
- Trimming and stretching the head
Bottle defect 10
Bottom blasting after making bottles with bottle blowing moulder
- The the delay of blowing is insufficient.
- The delayed mold opening time is too short
- The temperature is too high
- The exhaust valve is malfunctioning.
- Increase the stretching rod’s lowering speed or lengthen the delay blowing time.
- Extend the time it takes to open the door.
- Take a break
- Clean the exhaust valve with gasoline.
Bottle defect 11
The bottle’s bottom isn’t full when making PET bottles with PET bottle blower moulder.
- The bottle’s bottom temperature is too high.
- Inadequate or uneven vent holes in the mold bottle’s bottom
- The stretch rod hasn’t made it all the way to the bottom.
- The stretched head’s design does not match the shape of the PET preform’s bottom.
- Inadequate blowing pressure
- Inadequate flow of the blowing valve
- The bottle’s bottom curve is poorly designed.
- Lower the temperature in the heating zone at the bottom or use a damp cloth to lower the temperature in the PET preform at the bottom.
- Increase the number of vent holes and distribute them evenly.
- Place the stretch rod at the bottom of the bottle and tighten it.
- Switch out the stretch head.
- Increase blowing pressure
- Clean the blow valve with gasoline
- Increase the curve and streamline design of the bottom of the bottle
Bottle defect 12
Thickness of PET preform uneven when blowing bottled with PET blowing moulding machine
If the tooth part of the PET preform is in a specific position, it is the reason for the uneven thickness of the PET preform.
If the mold clamping line is at a certain position relative to the mold, it is a mold exhaust problem
Uneven heating of PET preform
The bottom of the mold has a poor design.
Improve the thickness of PET preform design
Increase the size of the vent at the bottom of the mold.
Improve the heating situation
Enhance the bottom design
Bottle defect 13
No power indication for the bottle blowing machine
- There is no electricity in the socket
- The insurance tube is broken
- The thread comes off
- The emergency safety switch is not activated.
- Whether or not the power is switched on
- The indicator light is damaged
- Whether the miniature circuit breaker of the control socket in the heating furnace is closed
- Check whether the socket has electricity and whether the leakage switch has tripped
- Check whether the circuit is short-circuited, and then replace the fuse
- Connect the connector
- Open the emergency safety switch
- The power switch is on
- Replace the indicator light
- Close the circuit breaker
Bottle defect 14
No sealing and stretching action
- The clamping stroke is not in place
- The mold clamping stroke switch is broken
- The wire falls off
- Delayed stretch time relay is damaged
- The lifting solenoid valve and the stretching solenoid valve are damaged
- Cylinder intake and exhaust throttle valves are blocked or closed
- Corresponding solenoid valve failure
- Set the delay stretch time to “0”
- Move forward the clamping block
- Replace the mold clamping stroke switch
- Connect the thread
- Replace the time relay
- Replace the solenoid valve
- Check the hole position to make sure it is unblocked
- Check the relevant solenoid valve
- The delay stretch time setting cannot be less than “0”
Bottle defect 15
The disc does not rotate
- The disc does not rotate because the fuse has blown.
- There is a problem with the AC contactor and the thermal relay.
- Motor phase loss
- Using a multimeter, measure the resistance of the fuse (R1); if it is 0, the fuse is good; if it is ∞, the fuse is broken.
- Measure the voltage at both ends of the AC contact coil with a multimeter ACV250. If it’s 0, check the voltage between the AC contactor coil’s upper end and the thermal relay (96). The thermal relay is damaged or overloaded if the voltage is 220V.
- Connect the phase wires
Bottle defect 16
Reason: The main motor current is too large, and the thermal relay overload current protection is cut off
Solution: Check the motor failure or adjust the overload current of the thermal relay
Bottle defect 17
Air switch adjustment
- A live wire short circuit and a voltage regulating circuit
- The motor stops working.
- The switch will trip if it is closed. Disconnect the heating air switch first, then reconnect it. It means the main circuit is short-circuited and grounded if it jumps again. One by one, turn off the air switches. It will jump when it is closed. This air switch’s voltage regulating circuit has a problem, so please check it one by one.
- If the motor is started and trips, it means there is a problem with the motor branch circuit
Bottle defect 18
The lamp does not light up
- The voltage regulating circuit is damaged
- The lamp filament is broken
- The SCR is damaged or disconnected
- The lamp tube is disconnected
- Measure the voltage at both ends of the lamp with a multimeter ACV250 gear
- If there is 220V, the lamp filament is broken, remove it, and recheck with multimeter R×1 file
- If it is “0”, check the corresponding voltage regulating circuit, first measure whether there is voltage output, and then whether there is voltage input, if there is input but no output, it is generally because the SCR is damaged or the potentiometer is disconnected.
- When the potentiometer is adjusted, the indicator light changes in brightness, which can indicate that the thyristor is intact, and it is concluded that the lamp tube is broken
Bottle defect 19
The stretch rod fails to rise and return to the original position after the mold is opened
- The magnetic pole switch’s position is too low, and the cylinder’s piston does not pass the magnetic pole switch after the stretch rod reaches the bottom of the stretch position.
- The stretching rod’s stretching speed is too high.
- Manually raise the stretch rod to its original position, then raise the magnetic pole switch to ensure that the piston is sensed by the magnetic pole switch when the stretch rod reaches the bottom of the position.
- Reduce the speed of the stretching rod by tightening the one-way throttle valve joint under the stretching cylinder in a clockwise direction. It’s worth noting that changing the speed of the stretching rod can have an impact on the blowing effect, which can be tweaked as needed. The “delayed blowing” time setting is adjusted to achieve the desired effect of blowing when the stretch rod reaches the bottle’s bottom.
The above is that we often encounter various blowing problems in daily production.
If you have more questions or want us to provide a targeted blowing solution, please feel free to contact us through the form below.
Please check the PET bottle blow moulder we’ve made.