Instructions
EPS Technical Instructions
Common problems and treatment methods of EPS processing
| Question | Reason | Solution |
| 1. Magnification is inversely proportional to density | Magnification = 1000/Density | Density = 1000/magnification |
| 2. Hair is not light (density fluctuation) | 1) Steam pressure is unstable | 1) Redesign of steam plant |
| 2) particle size is not uniform | 2) Use the same batch of raw materials | |
| 3) Mixing of multiple batches of raw materials | 3) Sampling and sending to laboratory for analysis | |
| 4) The foaming agent content in the original particles is too low | 4) Shorten the transportation cycle | |
| 5) The transportation cycle is too long and the ambient temperature is too high | 5) Pressurize or extend the steam time | |
| 6) Steam pressure is too low | 6) Slow down the feed rate | |
| 7) continuous foaming machine feed rate is too fast | 7) Check the steam quality | |
| 8) The water content in the bubble is too high | 8) Reduce steam pressure/speed up feed rate | |
| 9) Bubble collapse caused by excessive steam heating | 9) It should be controlled in 3~5 hours | |
| 10) The interval between the first advance and the second advance is too long | 10）P1/P2=1.5 | |
| 11) during the second foaming, the first foaming density should not be too low | 11) Selection of raw materials with large particle size | |
| 12) The particle size is somewhat small | 12) Conveying by warm air when discharging through the fluidized bed | |
| 13) Low ambient temperature in winter and easy to shrink | 13) The measuring cup is not 1000ml but 500ml, and the scientific and accurate measuring method is 5000ml | |
| 14) Incorrect density measurement method | ||
| 3. Pre-foamed particles agglomerate | 1) Pursuit of ultimate density | 1) Select a larger size |
| 2) Insufficient proportion of coating powder | 2) Appropriate addition of similar coating powder substances (such as washing powder) | |
| 3) Steam pressure is too high or temperature is too high | 3) Reduce steam pressure or heating time | |
| 4) The feed amount is too small or the residence time is too long | 4) Increase the feed amount or extend the foaming time | |
| 5) Unreasonable agitator speed or structure | 5) Improve mixing or shorten the foaming time | |
| 6) The foaming agent in the raw material is too low | 6) Adjust the balance between steam pressure/discharge height/feed volume and density, or use fresh raw materials | |
| 4. More coating powder | Coating powder mixer is not evenly mixed | The amount of coating powder added is about 1~2kg per ton, and the free coating powder will melt when foaming |
| 5. The size/appearance of the bubbles is irregular (continuous pre-hair machine) | 1) Foaming agent aspect ratio is too low | 1) Extended residence time |
| 2) Foaming machine is not insulated | 2) Strengthen the heat preservation performance of the machine | |
| 3) Unreasonable distribution of steam flow passage | 3) Inspect steam line and steam inlet | |
| 4) Short residence time in the pre-machine | 4) Raise the height of the discharge port or slow down the feeding speed |
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| 5) raw material beads of different sizes | ||
| 6. Flame retardancy is not good | 1) Mixed with ordinary materials | 1) Clearance/pipeline during recharging |
| 2) The surface of the plate is too fresh or the foaming agent is stored | 2) The plate should be ventilated and stored after cutting, and it will show apparent flame retardancy after one day-simple ignition will not | |
| 3) Failure to understand inspection criteria | 3) Strengthen learning GB2406/GB8624 and other national standards | |
| 7. Pre-foamed particles are too wet in the silo | 1) The pre-foaming rate is too fast | 1) Slow down the discharge rate |
| 2) Fluidized bed drying temperature is too low | 2) Increase the temperature so that the particles are not too dry, so as not to cause static electricity | |
| 3) Poor ventilation of silo | 3) Improve ventilation | |
| 8. The density of foam particles increases after entering the silo | 1) Bubbly directly from the fan blade through injury | 1) Use the Venturi conveyor |
| 2) Lack of necessary short stabilization period | 2) Properly heat to normal state on the fluidized bed before air delivery | |
| 3) Fan power is too large | 3) reduce the transmission power, should be controlled at 5~10 m/s | |
| 4) Too many corners or elbows, excessive resistance | 4) Reduce resistance and increase corner radius | |
| 9. Poor sintering | 1) The pentane content in the raw material is too low | 1) Sampling and sending to laboratory for analysis |
| 2) The curing time is too long | 2) Reduce curing time | |
| 3) excessive coating powder | 4) Improve mold exhaust performance | |
| 4) Die exhaust is not smooth | 5) Check the steam quality | |
| 5) Wet steam incorrect steam operation | 6) Extend the steam penetration time | |
| 6) The air in the mold blocks the heat transfer of steam | 7) Increase steam pressure | |
| 7) Steam heating pressure is low | 8) Extend the steam heating time | |
| 8) Steam time is too short | 9) Adjust the cross steam steps | |
| 9) Insufficient heating | 10) Shorten the water cooling time or increase the preheating step | |
| 10) The mold is too cold or too wet when feeding | ||
| 10. The molding cooling time is too long | 1) High pentane content in bubble particles | 1) Extend the curing time and enhance the ventilation of the silo |
| 2) Insufficient proportion of coating powder | 2) Sampling and testing | |
| 3) Large particle size | 3) Select the smaller one particle | |
| 4) The density is too high | 4) Reduce foaming density | |
| 5) Short water cooling time | 5) Extend the water cooling time | |
| 6) Low vacuum degree | 6) Check the air tightness of the mold or mold equipment | |
| 7) High cooling water temperature or low pressure | 7) Reduce water temperature or increase water pressure | |
| 11. Sheet shrinkage | 1) Advance mode is not normal | 1) The second advance interval is 3~5 hours, P1/P2 = 1.5-1.6, and the first advance density should not be too low. |
| 2) The curing time is too long | 2) Reduce curing time | |
| 3) High steam heating pressure | 3) Reduce steam pressure | |
| 4) Too low bubble density | 4) Increase bubble density | |
| 12. Plate cracking | Not enough cooling time | Extend cooling time |
| 13. Poor sheet fusion | 1) Low bubble density | 1) Increase bubble density |
| 2) Selection of small particle size | 2) Change to large size | |
| 3) The curing time is too long or too short | 3) Control the curing time | |
| 4) Steam contains too much water | 4) Check the steam quality | |
| 5) Poor hydrophobic effect of the trigger | 5) Improve the drain pipe of the plate machine |
Expandable polystyrene (EPS) is a small granular resin, widely used in the construction industry, Thermal insulation, sound insulation materials, seismic protective packaging materials and waterproof road water conservancy construction field.
Fushun Daluwang Composite New Material Co., Ltd.
Telephone:024-57199666
Address: No.16 -1, Shuangmian Road, Longfeng Street, Dongzhou District, Fushun City, Liaoning Province
Mailbox:597286037@qq.com