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Bubble injection molding process causes and solutions 0 replies,659 views


According to the bubble causes of the countermeasure in the following areas:
1) The wall thickness is large, the outer surface of the cooling rate faster than the center, therefore, carried out with the cooling, contraction of the center edge of the resin to the surface side of the expansion, so that the center produces less filling. This condition is called a vacuum bubble. Solutions are:
a) wall thickness to determine a reasonable gate, runner size. General wall thickness gate height should be 50% to 60%.
b) to seal the gate so far, leaving a supplementary injection of material.
C) injection time should be slightly longer than the gate sealing time.
d) reduce the injection speed, injection pressure increased,
e) a high melt viscosity grade material.
2) As a result of the generation of volatile gas ****, the solution are:
a) the full pre-drying.
b) reduce the resin temperature to avoid decomposition of gas.
3) The poor mobility due to ****, and the mold by raising the resin temperature, increase the injection speed to be addressed.

Disadvantage because of improvement measures
1) The injection volume of less than 1) to adjust the injection volume
2) The melt flow of less than 1) increasing the injection pressure
2) increasing the temperature of the nozzle barrel
1. Injection mold unsaturated 3) Increase mold temperature
4) increasing the injection time & speed
3) does not correct mold design 1) strengthen the entrance channel, the outlet.
2) improving the entrance channel, the design of outlet
3) improving the entrance position
4) increased vent
2. Finished brittle 1) heat 1) to reduce the cylinder temperature
2) reduce the molding cycle
2) with the stress of 1) increasing the cylinder temperature
2) reduce the injection pressure
3) increase the molding cycle
4) Increase mold temperature
5) Increase the entrance channel, the outlet.
3) binding wire (Weld Lines) 1) increase the injection pressure
2) increasing the injection time & speed
3) increasing the cylinder temperature
4) Increase mold temperature
5) combined with an additional line at the overflow stream and then cut the Department of
6) change the location and design of the entrance
7) Improved vent
(4) finished the lack of moisture. 1), the product moisture treatment
5) poor quality recycled materials. 1) The ratio of green to add new
3. Finished with lack of fusion particles 1) the resin is not fully melt 1) increasing the cylinder temperature
2) increasing the molding cycle
3) The ability to plastics injection molding machines with high
4) Increase back pressure
4. Finished surface depression 1) melt enough to fill 1) increasing the injection time & pressure.
Or within the space. Low sales finished cooling 2) increasing the mold temperature. (But not for the surface depression)
After the heat shrink. 3) Less fro cylinder temperature
4) resin fully dry or addition agent to reduce the Run
Injection pressure loss
5) Increase the entrance channel, the outlet.
6) When finished with voids. Reduce the injection speed.
Disadvantage because of improvement measures
5. The surface of linear gas lines 1), high temperature gasification. 1) to reduce the cylinder temperature
Wrinkles, such as fish eyes. 2) to reduce the temperature of the nozzle barrel
3) to reduce the molding cycle, or use the small feed tube.
2) resin moisture 1) and then dry.
2) the use of packaging is not broken resin.
3) Possession of dead material. 1) and the nozzle barrel is designed to streamline.
4) The entrance of the poor design. 1) to increase or change the location of the entrance Chiduo.
6. Scorch 1) Die bad exhaust air 1) reduce the injection pressure. Reduce the injection speed.
Forced pressure in the cavity. 2) improving the mold exhaust.
3) change the entry location, size and type
7. Finished mold 1 stick) of the resin injected into the mold cavity 1) reduce the injection pressure. Time. Speed.
Ministry of too much or more than the contraction entrance. 2) reduce the mold temperature.
3) to reduce cylinder temperature
4) extend the cooling time.
2) mold design. 1) Check UNDERCUTS within the slot.
2) Check the top of the system
3) increase in ejection angle. (R 3 - 5)
8. Burrs. 1) lack of clamping pressure. 1) reduce the injection pressure. Speed.
2) to reduce cylinder temperature
3) Reduce mold temperature.
4) reduce the injection volume.
5) increasing the amount of clamping pressure.
2) mold mismatch or 1) and then polished arrangements mold surface.
Template curve. 2) after the use of thicker template.
3) Check the model surface is a foreign body.
9. Finished warpage. 1) in two different mold temperatures. 1) to determine the average temperature of the mold.
2) over-contraction. 1) Reference 11.
3) and the thickness does not mean 1) the redesign of the mold.
Changed so much. 2) the two halves of different mold temperatures.
3) Use cooling fixtures.
4) extend the cooling time.
4) is not fully cured before the top out. 1) extend the cooling time.
2) reduced die temperature.
3) Increase the top of the area.
5) injection direction. 1) change the entry location.
(Especially with fiberglass resin) 2) to contain the glass resin.
Disadvantage because of improvement measures
9. Finished warpage. 6) were not tough. 1) The increase in thickness of the finished product.
10. Spray marks (JETTNG) 1) melt filled fast. 1) reduce the injection speed.
2) changing the entrance location and type. (Such as the side entrance).
11. Shrink too much. 1) of the molding conditions. 1) reduce the mold temperature.
2) increasing the injection pressure
2) The entrance is too small. 1) increase the entrance.
12. Lamellar separation. 1) incompatible with foreign objects. 1) Check the resin. (Especially recycled material)
(LAMINATION) 2) filling the cavity lead to 1) increase the mold temperature. Cylinder temperature
High impact. 2) reduce the injection pressure. Speed.
13. Surface cracks and ****. 1) The cold surface of the mold cavity. 1) increase the mold temperature.
2) reduce the injection speed.
3) Insert the pieces to warm up.
14. The surface of glass such as a blanket-like. 1) improper injection speed. 1) increase the injection speed & pressure
2) increasing the cylinder temperature
3) Increase mold temperature
15. Retardant specifications of color 1) overheating. 1) to reduce the cylinder temperature
And embrittlement 2) reduce the molding cycle

Improvement measures difficult because the surface defect (SURFACE 1. Cold Plastic 1) increasing the temperature of plastic
IMPER PECTIONS) 2. Die temperature is too low 2) increasing the mold temperature, mold temperature controls, or increase the section
(See Silver rhyolite, shrink 3. Shoot material application machine is too slow 3.A control system, boost the speed trap column with the jack, black rhyolite, the melting line and increase the injection velocity and flow pattern) B. the most strongly and quantitative or pre-shot plastic material feed
4. Inlet and plastic flow channel 4) of the feed inlet and double plastic flow was balanced feed
Material flow balance
5. Mold plastic flow of material adverse 5) re-export or re-arrange the feed product does not melt the plastic design 1. Plastic temperature is too low 1) increase the temperature of plastic
(UNMELED 2. Cycle too fast or the barrel of energy less than 2) extend the cycle time.
GRANULES 3. Material flow limit is less than 3) the use of limited material injection nozzle product deformation 1. Finished top of the plastic when the lower temperature hot 1.A
(WARPING) B has not yet solidified lower die temperature
C extension of time to mold
2. Plastic barrel temperature increase of the temperature is too low 2.A
B increase in mold temperature
3. 3.A thickness irregularity or product side of the use of non-temperature mode
The shape of the particular thickness of each part B so that the same product
4. 4.A much less feed feed
B reduce the injection pressure
5. One or more feed ports, each 5) limit the flow through the feed inlet of the plastic is only possible
Imbalance in the feed material inlet near the main channel at the limited pressure

6. The top of the poor design of the system, 6) re-design
Or adverse action
7. Mold temperature inconsistencies 7) Maintain mold surface at the same temperature
8. 8.A. fill around the feed inlet to increase or decrease forward speed jack column
B. squeeze too much material to reduce or increase the size of the feed port
Silver rhyolite 1. Plastic temperature is too high a) reducing the barrel temperature, injection material from the mouth of the temperature started to drop.
(SILVER 2. Plastic and particle size of 2) Avoid uneven granular materials
STREAKS) uneven mixing or recycling materials had to be the same size
3 plastic temperature is inconsistent, because: 3):
A. mouth or injection barrel temperature material A. Material mouth and reduce the fire barrel temperature
B. plasticizing capacity of more than machine B. extended period, or heat a large quantity of machines
C. hopper plastic temperature is inconsistent. C. warm material, or by loading the oven temperature consistent with the material hopper

Difficult because of improvement measures
Silver rhyolite 4. In the cooler end of the machine, the air 4) reduce the temperature of barrel section, and avoid the use of recycled materials.
(SILVER aggregation of particles in the material free.
STREAKS) 5. Materials attached to the water vapor. 5) The material dried before use.
6. Material in the cavity 6) A mouth to feed the same feed.
Mobility gap. B resettlement Inlet.
C maintain the mold temperature consistent.
D as the thickness of the product line.
7. Outside the lack of release agent. 7) plus zinc stearate 15g/100 pounds (recycled material)
8. Outside the release agent is inconsistent. 8) increase in mixing time. Or add a little lubricant.
9. Injection speed too fast. 9) A increase in vent.
B & speed & reduce the injection pressure to reduce the cylinder temperature
10. Outside the excessive release agent 10.) Increased the proportion of recycled material with or without release agent material.
11. Mold temperature is too low. 11) to increase mold temperature
12. Injection pressure is too high. 12) to reduce the injection pressure
Poor weld line 1. Plastic temperature is too low. 1) A cylinder temperature & increase mold temperature
(Or was). B increased injection pressure
C extended period of time.
2. Weld line is too far away from the feed inlet. 2) reposition the feed inlet. (Location).
3. Air exclusion was not quick enough. 3) The exhaust system improvements.
4. Thickness of the product is not enough. 4) the redesign of products.
Or more to improve entrance and exit locations.
6. Mold temperature is too low 6) Increase mold temperature
7. Pressure is insufficient. 7) increase the pressure.
8. Injection material is too slow. 8) The rate of increase in shoot material.
9. Gas aggregation. 9) The addition of Yi to the top hole.
Shrinkage limit 1. Mold plastic enough to withstand
(SINKMARKS) cooling contraction. Due to: 1
A. Product part thickness, mold repair or A. or increase injection pressure
Prominent part.
B. lack of feed. B. & increase the pressure to increase feed
C. JI column ahead of time too short. C. jack column ahead of time to increase
D. Injection pressure is too low. D. increase the injection pressure
2. Materials in water vapor. 2) Material dried before use.
3. Mold temperature is uneven. 3) re-arranged by water temperature. The mold temperature consistent.

Cracks or broken. 1. Excessive pad squeeze. 1.A: reduced shot feeding amount.
(CRACKINGOR B; reduce the injection pressure
CRAZING) 2. Mold temperature is too low. 2) increasing the die temperature
3. Ejection angle improper or depression. 3) amend the mold.
4. The top off. Wrong place. 4) Top off the top of the force should be balanced.
Out better than the top of the product.
Size changes. 1. Operating conditions unstable. 1). Operating conditions consistency.
2. Molding conditions unstable. 2.) Consistency of the molding conditions.
(Mold temperature cycle, temperature and pressure material feeding voltage ... ..)
3. The ambient air temperature and humidity 3) consistency conditions.
Rough surface of the product. 1. Mold temperature is too low. 1) increase the die temperature
(DIMCNSIONAL 2. Injection pressure is too low. 2) to increase injection pressure
VARIATION) 3. Die face with water vapor. 3) remove or repair the leak. Or to avoid the coalescence of water vapor.
4. Mold release agent over the surface. 4) reduce or remove surface mold release agent.
5. The plastic so that not less than 5) A increase in injection pressure
Plastic complete access to the cavity. B radiation feeding amount increased
C increase in mold temperature
6. Ji chu forward speed is too low. 6) A temperature increase of pump column.
B increase in the plastic temperature.
Short plastic 1. Plastic temperature high enough. 1) to increase the plastic temperature.
(SHORT SHOTS) 2. Mold temperature is too low. 2) increasing the die temperature
3. Injection pressure less than 3.) Increasing the injection pressure
4. Mold temperature inconsistencies 4) Reinstall the water.
5. Shoot feeding amount less than 5.) Increased shoot feeding amount
6. The air together. 6) or greater increase in vent vent.
7. Release agent insufficient. (Plus a). 7) increased release agent.
8. Ji chu ahead of time is too short. 8) increase in pump column ahead of time
9. Injection material is too slow. 9) The rate of increase in shoot material.
10. Inlet is too small. 10) to increase the feed port.
Brown rhyolite. 1. The whole or part of the barrel from overheating. 1) reduce the temperature.
(BROWNSTREAKS) 2. Barrel plug or injection nozzle material. 2), mouth wash barrel shot material.
Inside the bubble 1. For the following reasons to Die
(BUBBLUS) materials can not withstand excessive contraction
A thicker parts. Prominence. A) modify the mold.
B injection pressure is insufficient. B) increase the injection pressure
C. JI column ahead of time too short. C) increase the jack column ahead of time
D. radio feed is too slow. D) increase the rate of injection material.
E. Inlet is too small. E) increase the feed inlet.
2. The plastic temperature is too high. 2) to reduce the plastic temperature. (Barrel & nozzle)
Can not be divorced from the mainstream channel. 1. Injection pressure is too high. 1) reduce the injection pressure
(SURUE 2. The plastic temperature is too high. 2) to reduce the plastic temperature. (Barrel & nozzle)
STICKING) 3. Sprue too long. 3) The narrow main road.
4. Feeding quantity too .. 4) reduction of feeding quantity
5. Ejection angle of less than 5) to increase ejection angle
6. Vertical gate (sprue) radio feed nozzle 6) hole injection nozzle material should be less than the vertical gate (sprue)
Mismatch 7), touch nothing left to eliminate the surface of depression
7. Depression or surface roughness 8) ahead of time to reduce Ji-chu
8. Ji chu stay too long and 9) reduce the feeding quantity of feed opening part or sheet 1. Not a material temperature) increases the plastic temperature.
Group stake 2. Mold temperature is too low. 2) increased die temperature
(LAMINATION 3. Injection slowly 3) increase the injection speed
AT GATE) 4. Pressure less than 4) increase the pressure
5. Squirt column (Lo defended) stay too long 5) reduce feeding time radio
6. Materials, cleaning of contaminated feed tube 6.A.
B. Avoid mixing with other plastics
7. Release agent over 7) Clean mold surfaces, and occasionally use
8. Plastic flow and the feed opening is too large or 8) trimmed plastic flow, the double pressure control was better
Too small
9. Mold temperature is too high, especially in the main channel 9) in the hot mold surface using the auxiliary cooling equipment
Or central feed port
Mucosal (PARTS 1. Injection pressure or barrel temperature 1). Lower injection pressure or barrel temperature
THE MOLD) 2. Feed too much 2) to reduce feed
3. Squirt forward too long column 3) to reduce Ji column ahead of time
4. I expected to write deep into imbalance, 4) limit the plastic flow, as close as possible sprue
Or single write mode is not the Inlet
Balance 5) to eliminate depression, increase the ejection angle of lighting or
5. Die in sunken part of the 6) to provide adequate airway Plaza
6. Deep stripping vacuum tube piece 7) to maintain a fixed mold time, and if necessary,
7. Opening time changes should use the timer mode
8. Mold surface cleaners improper 8) polishing the surface of Writing
9. Modulus heart dislocation 9) adjustment mode heart, and use the pull back angle lock of the excess material (FLASH) 1. Materials to reduce the material temperature is too hot 1.A.
B. reduce the mold temperature
2. The pressure is too high reduce pressure 2.A.
B. reduce the step-up time
3. Over-shoot material 3) reduction of feeding
4. Shoot material instability 4) maintaining the front jack column, the same amount of material
5. Parting line or close the membrane surface negative 5) to re-modification of the mold parting line or surface
6. Cycle time instability 6) The use of timers to maintain the full cycle of the same
7. Mold mold pressure increases the pressure less than 7.A.
B. raised to a greater pressure mold plastic machine production of rhyolite (FLOW 1. Plastic temperature is too low a) increase the temperature of plastic.
LINES) 2. Mold temperature too cold 2) increasing the die temperature
3. Erzhi feed inlet is too small overflow 3) increase the feed inlet and reduce the injection speed
4. 4.A. inconsistent thickness of the various parts of product re-design products, and Shuang have a uniform thickness
B. Elimination of tilting cycle of projections or pelvic cavity instability 1. To keep the mold open time 1) using the open mode timer, the cycle time to maintain a fixed
(CYCLES) 2.A. variable length to maintain sufficient pressure to shoot the same material
2. Pressure instability B. Check whether the oil pressure system
3. 3.A. check the barrel temperature is inconsistent temperature control system to maintain the normal operation
B. Temperature Control System using the best
C. Check the voltage, and make it stable
D. determine the heater is working
E. In the material into the hopper before the barrel of the material should be maintained
Same temperature
F. In the front of the jack column material, the amount should remain the same
G. machinery should be maintained in a balanced condition
4. 4.A mold temperature is inconsistent with the mold temperature controller
B. should be the appropriate channel mold
C. mold should have the appropriate exhaust stout home
D. usually die in the water should have appropriate fittings

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