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Direct answer: For paper bag rope adhesion, hot melt adhesive particles with high initial adhesion, good flexibility, and a softening point of 75-85 ℃ should be used. The diameter of the adhesive point should be 8-12mm, with one point at each rope hole. Press and hold for 3-5 seconds.The key is not in the amount of glue, but in the accurate positioning and proper pressing of the glue points.

The latter two types have significantly higher requirements for the peel strength and flexibility of the adhesive, and should not be mixed with the sealing adhesive when selecting the adhesive.
| parameter | Suggested scope | Reason |
|---|---|---|
| softening point | 75–85℃ | Too low summer transportation is prone to softening, while too high and low temperatures can cause brittleness |
| Melting viscosity (180 ℃) | 2500–5000 mPa·s | Too thin will penetrate the back of the paper, and too thick will result in poor adhesion |
| Opening hours | 3-6 seconds | Manual gluing requires leaving a margin for operation |
| flexibility | After curing, it can be bent without cracking | The direction of force on the lifting rope changes repeatedly |
Handheld glue guns or small dispensing machines are generally used for manual production lines, with a melt adhesive temperature set at 170-180 ℃. After starting up, do not rush to apply glue. First, empty 3-5 shots to drain the residual glue in the pipeline, to avoid black residue or insufficient glue in the first batch of products. The semi-automatic line uses a dispensing valve, set the dispensing time to 0.15-0.3 seconds, and first try to apply the glue on the waste paper to confirm the size of the glue point.
Select 10 pieces from each batch and conduct two tests: one is static load test, where a 5kg weight is placed in the bag and lifted for 60 seconds without detachment; The second is the peeling test, which involves manually tearing the rope at the fixed point. The qualified standard is that the paper is torn but the adhesive dots do not fall off as a whole. If the adhesive dots are cleanly peeled off from the paper, it indicates insufficient initial adhesion or penetration, and the temperature needs to be increased or the model needs to be replaced.
Q: Can we use sealing rubber particles instead?
Answer: Not recommended. The sealing adhesive is too hard and prone to cracking when bent after curing, resulting in a short lifespan when used at the rope lifting position.
Q: What should I do if the adhesive dots turn yellow or have black residue?
Answer: It is mostly due to the long-term high-temperature storage and carbonization of the glue in the glue pot. Reduce standby temperature, clean the pot in a timely manner, and avoid mixing different brands of granules.
Q: What is the reason why ropes tend to break during winter lifting?
Answer: The adhesive layer becomes brittle at low temperatures. Need to replace the cold resistant formula or choose a model with slightly lower softening point and better flexibility.
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