Blow Molding Machine Introduction and Frequently Asked Questions



Blow Molding Machine Introduction and Frequently Asked Questions
                       
 
Introduction of Blow Molding Machine

1. Types of blow molding machines. Currently, PET two-step blow molding machines include rotary automatic blow molding machines, linear automatic blow molding machines, and manual semi-automatic blow molding machines.

2. The structural part of the bottle blowing machine is changed to a bottle preform lifting system, a blank pretreatment system, a blank separating system, a transmission system, a heating system, a bottle blowing system, and a bottle taking system (such as a mold base, stretching, and air blowing).

3. Ancillary equipment, the operation of the blow molding machine is changed to the supply of low-pressure air compressor system (air compressor host, storage cylinder, filter system, cold and dry machine) and electric mode (servo motor). Compressor system (mainframe of high-pressure air compressor, storage cylinder, filter system, cold-dryer) In addition, cold water machine (because the bottle to be blown out must be quickly shaped)

 

Blowing principle

When the processed PET pipe blank reaches a certain temperature after being heated, it is stretched and extended again, two blows are blown, the second blow is blown to maintain pressure, and then the exhaust is completed.

 

Problems and solutions of blow molding process

Fault 1: The transparency of PET bottles is never good. Reasons: 1. The heating temperature is so high 2. The heating time is too long 3. The compressed air contains moisture 4. The injection embryo tube itself is never transparent 5. The embryo tube design is not comfortable 6. The inflation ratio Very small

Exclusion methods: 1. Reduce temperature 2. Reduce heating time 3. Remove water from dryer 4. Improve the quality of embryo tube, choose materials and improve the dryness of raw materials 5. Improve the design of embryo tube size 6. Reduce the diameter of embryo tube

Trouble 2: Pearl gloss appears white on PET bottles. Reasons: 1. The heating temperature is too low. 2. The thickness of the embryo tube wall is not uniform. 3. The thickness of the embryo tube is very thick.

Exclusion methods: 1. Increase the temperature or slow down the revolution speed 2. Improve the quality of the embryonic tube 3. Reduce the thickness of the embryonic tube or try to raise the cover of the heating device to increase the temperature of the surface layer of the embryonic tube

Fault 3: The westward position of the PET bottle's nozzle is shifted to the west. Reasons: 1. The blowing time is very early. 2. The stretching rod is not lowered to the end. 3. The centerline of the stretching rod and the bottle axis is shifted to the west. 4. The wall thickness of the embryo tube is never Homogeneity or injection density

Exclusion methods: 1. Delay the blowing time or increase the lowering speed of the stretching rod 2. Adjust the position of the magnetic pole switch 3, adjust the position of the stretching rod 4, improve the quality of the embryonic tube 5, improve the heating conditions, or check the rotation of the embryonic tube No question

Fault 4: The thickness of the PET bottle wall is not uniform. Reasons: 1. The position of the stretching rod is never at the center of the embryo tube 2. The blow hole is never asymmetric, and the hole diameter is never the same 3. The stretch ratio is so low or the inflation ratio is very small 4. The embryo tube never turns in a heating furnace 5. The wall thickness of the embryo tube or the injection density never varies

Exclusion methods: 1. Adjust the position of the stretching rod 2. Adjust the position of the blow hole and the aperture 3. Increase the stretching ratio or inflation ratio 4. Check the rotation device 5. Improve the quality of the embryo tube

Fault 5: The lower part of the bottle is very thick Cause: 1. The temperature on the upper part is too low 2. The position of the mold vent hole is far from the lower part 3. The stretch ratio is too low 4. The inflation ratio on the upper part of the bottle is too low 5. The speed of the stretch rod is very slow

Exclusion method: 1. Warm the upper part 2. Adjust the position of the exhaust hole 3. Increase the stretching ratio 4. 4. Change the shape of the bottle. Adjust the speed of the stretch rod. Fault 6: The bottle bottom is very thin. Reasons: 1. The air blowing time is too early. 2. The top temperature is so high. 3. The top of the embryo tube is very thin.

Exclusion method: 1. Delay the start of blowing time 2. Reduce the top temperature 3. Increase the thickness of the top of the embryo tube

Fault 7: The mold clamping line of the bottle is obvious. Reasons: 1. The clamping pressure is never enough. 2. The sealing time is too early. 3. The mold problem. 4. The size of the embryo tube mouth and the mold fit are never the same.

Remedy: 1. Increase the clamping pressure, adjust the clamping brace angle (<5 degrees) 2, then move the clamping stroke switch position 3, repair the mold or check the mold assembly position, such as whether the guide column is loose, Or whether the mold has not been compressed.

Fault 8: The top of the bottle or the bottle neck is rolled up, the reasons for the accumulation of material: 1. The delayed blowing time is very long 2. One roll, a good one 3. The temperature of the accumulation place is very low 4. The air pressure used in the operation is absolutely unstable, which affects the pull Falling speed of pole

Remedy: 1. Shorten the delayed blowing time or reduce the lowering speed of the stretching rod. 2. Reduce the air volume on the side of the bottle. 3. Increase the heating temperature of the embryo tube. 4. Add an air storage tank to the operating gas source or Is to shorten the gas supply line

Failure 9: Stretch perforation at the bottom of the bottle Reason: 1. The temperature is not enough and has not penetrated 2. The extended stretch time is very long 3. The stretch is too high 4. The top of the embryo tube is very thin 5. The stretch head is very sharp

Exclusion methods: 1. heating 2. shortening the delay stretching time 3. reducing the stretching ratio 4. improving the design of the top of the embryo tube 5. rounding and stretching the club head

Failure 10: Bottom of the bottle burst Cause: 1. Very short delayed blowing time 2. Very short delayed mold opening time 3. Very high temperature 4. The exhaust valve will never work

Exclusion method: 1. Lengthen the delayed blowing time or increase the lowering speed of the stretching rod 2. Increase the delayed mold opening time 3, cool down 4, clean the exhaust valve with gasoline

Fault 11: The bottom of the bottle is never full. Reasons: 1. The temperature at the bottom of the bottle is very high. 2. The exhaust holes at the bottom of the mold are insufficient or uneven. 3. The stretch rod has never reached the top. 4. The design of the stretch rod head is never full. Conform to the shape of the embryo tube top5, the blowing pressure is less than 6, the blowing valve flow is less than 7, the curve design of the bottom of the bottle is never good

Exclusion method: 1. Reduce the temperature at the top of the heating zone or use a damp cloth to reduce the temperature at the top of the embryo tube 2. Increase the number of vent holes and make them evenly distributed 3. Adjust the stretching rod to the bottom of the bottle 4. Replace the stretching rod head 5. Increase the blowing pressure 6. Use gasoline to clean the blowing valve 7. Increase the curve design of the bottom of the bottle

Trouble 12: 1. If the teeth of the embryo tube are in a certain position, it will also be the cause of the uneven thickness of the embryo tube. 2. If it is in a certain position relative to the mold clamping line, it will also be a problem of mold exhaust. 3. The tube is heated. Never uneven 4.The design of the mold top is never good

Exclusion methods: 1. Improve the thickness of the embryo tube 2. Improve the vent holes on the top of the mold 3. Improve the heating conditions 4. Improve the design of the top

Fault 13: No power indication for bottle blowing machine Reasons: 1. No power at the socket 2. Broken fuse 3. The wire is disconnected 4. The safety emergency switch is not turned on 5. Whether the power switch is turned on and placed at 6. The indicator light is damaged 7. The heating Whether the miniature circuit breaker of the control socket in the furnace is closed

Remedy: 1. Check if there is power in the socket, whether the leakage switch is tripped 2. Check if the circuit is short-circuited, then replace the fuse 3, connect the connector 4, turn on the emergency safety switch 5, turn on the power switch 6, and replace the instructions Light 7, close the circuit breaker

Fault 14: No sealing and stretching action reasons: 1. The mold clamping stroke is never in place 2. The mold clamping stroke switch is broken 3. The wire is disconnected 4. The delay stretch relay is damaged 5. The lift solenoid valve and the stretch solenoid valve are damaged 6 、 Cylinder intake and exhaust throttle valves are blocked or shut down 7. Corresponding solenoid valve failure 8. Delayed stretch time is set to “0”

Exclusion method: 1. Move the mold clamping block back 2. Replace the mold clamping stroke switch 3. Connect the thread connector 4. Replace the time relay 5. Replace the solenoid valve 6. Check the hole position to ensure smooth flow 7. Check the relevant solenoid valve 8. The setting of the stretching time must not be less than "0"

Fault 15: The disc never turns Cause: 1. The fuse is broken, the disc never turns 2. The AC contactor and thermal relay are damaged 3. The motor is out of phase (humming)

Exclusion method: 1. Use a multimeter to block (R × 1) to measure the resistance of the fuse. If it is 0, it means that it is good; if it is ∞, it means that it is broken. 2. Use multimeter ACV250 to measure the voltage across the AC contact coil. If it is 0, then measure the voltage between the upper end of the AC contactor coil and the thermal relay (96). If it is 220V, it also indicates that the thermal relay is damaged or overloaded. Phase line

Fault 16: Alarm sounding Cause: The main motor current is so large, and the thermal relay is so loaded with current protection to power off

Remedy: Check motor fault or adjust thermal relay current

Fault 17: Air switch adjustment Cause: 1. Short circuit of live wire and voltage regulator circuit 2. Motor burned out

Remedy: 1. If the switch is closed, it will trip. First disconnect the heating air switch, and then close it. If it jumps again, it also indicates that the main circuit has a short circuit to ground. Close the air switch one by one. Jumping also indicates that there is a problem with one of the voltage regulating circuits of this air switch. Check again one by one. 2. If the motor starts, it will trip, and it also indicates that there is a problem with the motor branch.

Fault 18: The lamp never turns on Reason: 1. The voltage regulator circuit is damaged 2. The lamp filament is broken 3. The thyristor is damaged or disconnected 4. The lamp is disconnected

Remedy: 1. Measure the voltage across the lamp with ACV250 in a multimeter. 2. If there is 220V, the lamp filament is broken. Remove it. Use a multimeter R × 1 to review. 3. If it is “0”, check the corresponding voltage regulator circuit. Measure the voltage output first, and then check the voltage input again. If there is input and no output, it is usually that the thyristor is damaged or the potentiometer is unsoldered. 4. If the potentiometer is adjusted, the indicator light changes. The thyristor is intact, and it is determined that the lamp is disconnected.