In the production process of waterproof sandpaper, it is inevitable that defective products will occur. For the situations that may occur and preventive measures, the following is an analysis.
1. Surface and sharp
Reason: The amount of glue applied is too large; the quality of the abrasive is poor; the drying time is short and the temperature is low, not completely dry.
Prevention: Appropriate coating; improve abrasive quality and basic particles; drying temperature and time must be guaranteed.
2. Desanding
Reason: The amount of glue applied is too small; the drying time is not enough and the temperature is too low.
Precaution: The amount of base glue and compound glue should be properly controlled; The finished waterproof sandpaper must be dried for a specified temperature and time.
3. Poor softness
Reason: The drying time is too long and the drying temperature is too high; the amount of amine varnish is too large.
Prevention: The drying time and temperature must be strictly controlled; the formula process must be strictly followed; semi-finished waterproof sandpaper should be stacked in a ventilated place.
4. Lack of glue and sand
Reason: The rubber roller is dirty; the rubber surface is scratched; the sand box is clogged.
Prevention: Use caution; clean frequently.
5. Glue edge on the back
Reason: There is glue on the breast roller; the base body is deviated.
Prevention: Keep breast rollers clean; handle with caution.
6. Sand ball
Reason: Jelly; lumps on paper surface; abrasive agglomeration; paint leather and impurities; base glue is too thick.
Precaution: The abrasives must be screened before use; waterproof sandpaper is required to be flat; the abrasives must be dry; the paint must be screened; the base rubber must be of moderate thickness.
7. Coarse grain
Reason: The abrasive is mixed with coarse materials; the sand planting equipment is not kept clean.
Prevention: Pay attention to the storage of waterproof sandpaper and abrasives; when exchanging particle sizes, the sand planting equipment must be thoroughly cleaned.
8. Fold print
Reason: The base paper wrinkles due to moisture; the tension is too large or too small during production; it is too tight or too loose during winding; uneven drying.
Precaution: Keep dry; handle with caution.
9. Trademark unclear
Reason: The trademark roller is worn; the amount of ink is too small; the trademark roller is not pressed tightly.
Prevention: Replace the trademark roller in time; pay attention to the amount of ink used; operate with caution.
10. Translucent
Reason: The base paper has poor water resistance and different tightness; the impregnation thickness is not enough.
Prevention: Improve the quality of waterproof sandpaper base paper; pay attention to the appropriate impregnation thickness.
11. Painted face
Reasons: Uneven sanding; insufficient pre-drying, serious desanding during winding or lamination; uneven sanding.
Prevention: Uniform and moderate glue thickness; appropriate pre-drying; uniform sanding and keeping the sanding roller clean.
