1. Film falling off the lower film

Phenomenon: The lower film falls off the chain and cannot move synchronously with the chain, resulting in abnormal stretching and packaging of products.

Reason:

(1) The width of the lower membrane is narrow.

(2) The chain is not tightly clamped.

(3) The membrane is biased.

Solution:

(1) Widen the cutting width of the lower film to ensure that it matches the width of the chain.

(2) repair the chain clamp.

(3) Adjust the position of the lower film so that the center of the lower film coincides with the center of the chain.

2. Poor stretch forming effect

Phenomenon: The film is torn or poorly formed after stretching

Reason:

(1) The heating amount of the heating plate is not enough.

(2) When the heating temperature is not matched, if it is too high, the film will stick to the heat seal plate, which will increase the haze of the film, and local thinning will occur in stretch forming. When the heating temperature is too low, the heating temperature of the film is low, which can not reach the stretching temperature of the film, and it breaks more after stretching.

(3) The drawing depth is too deep.

Solution:

(1) Maintain the heating plate to make it heat normally, so as to ensure sufficient heat supply.

(2) reduce or increase the temperature of the heating plate and adjust it to a suitable temperature range.

(3) The film should be used correctly in the effective stretching range. The film with deep stretching should be stretched with a thicker film, and the film with shallow stretching should be stretched with a thinner film, which not only ensures the product quality, but also reduces the production cost.

3. Poor heat sealing

Phenomenon: The upper and lower films are separated and layered after heat sealing or sterilization.

reasons:

(1) the heat sealing temperature is low, which can't meet the needs of the inner layer heat sealing temperature.

(2) One or both of the upper and lower films have wrong thermal cover inside and outside.

Solution:

(1) Raise the heat sealing temperature to reach the required temperature of the inner layer heat sealing material, but not too high, otherwise, the phenomenon of sticking the heat sealing plate and the deformation of the upper film will occur.

(2) adjust the thermal cover of one or both of the upper and lower films to ensure that the heat sealing surfaces of the upper and lower films are corresponding.

4. There is air in the product packaging

phenomenon: there is air in the film after the heat sealing plate is discharged.

Reason:

(1) The width of the upper film is larger than the width of the heat-sealing plate, so the vacuum-pumping air hole of the heat-sealing plate is blocked and the air between the upper and lower films is pumped.

(2) The vacuum extractor is out of order, and the vacuum pumping effect is poor.

(3) The vacuumizing air hole in the heat sealing plate is blocked by foreign matter.

(4) The heat sealing effect is poor, and some air leaks.

(5) When the upper and lower films are heat-sealed, the upper film deviates from the lower film, resulting in some poor heat sealing.

(6) When the lower film is stretched, there are holes that are torn and there is air leakage.

(7) There are holes in the upper membrane, resulting in air leakage.

(8) If the heat sealing temperature is too high, there will be holes in the upper film and air leakage.

(9) There is a gap in the heat sealing gasket.

Solution:

(1) Adjust the width of the upper film to an appropriate width to match the heat sealing plate.

(2) maintain the vacuum machine.

(3) Repair the heat seal plate, take out the foreign matter, and ensure smooth air holes.

(4) Improve the heat sealing temperature and compressed air pressure to ensure the heat sealing is in good condition.

(5) Adjust the upper film and match it with the lower film, so that there can be no deviation between the upper and lower films, and ensure good heat sealing of the upper and lower films.

(6) Improve the stretching effect of the lower film, and ensure that there is no pinhole after the lower film is stretched.

(7) Replace the upper membrane and adopt a good upper membrane to ensure no air leakage.

(8) Under the condition of good heat sealing, reduce the heat sealing temperature as much as possible to prevent the upper film from being burnt.

(9) Adjust the heat sealing gasket to make it a complete sealing surface.

5. Discount problem

Phenomenon: wrinkles on the film after product packaging.

Reason:

(1) The heat sealing temperature is too high, and the film is subjected to too much heat, so the upper film shrinks.

(2) When the machine is stopped, the upper film stays in the heat sealing plate for a long time, and the film is mostly subjected to heat, and the film shrinks.

(3) There are wrinkles on the film before heat sealing.

(4) There are foreign objects on the heat-sealing plate or there are scars on the heat-sealing plate.

(5) the heat sealing gasket is uneven.

Solution:

(1) Reduce the heat sealing temperature, reduce the heat of the upper film and reduce the shrinkage of the upper film.

(2) In order to ensure the continuous operation of the membrane, reduce the number of start-up and shutdown, so as to reduce the problem that the upper membrane is heated too much during shutdown, and avoid wrinkles caused by multi-shrinkage deformation of the upper membrane when heated.

(3) There are wrinkles on the film before heat sealing. If it is on the film, the quality of the product should be controlled in the production process to avoid wrinkles; If the lower film has wrinkles before stretching, it is required to control the quality of the product in the production process to avoid wrinkles; If the lower film is wrinkled in the stretching process, it means that the lower film is heated too much in the stretching process, and the stretching temperature, stretching preheating time and stretching forming time are reduced; Or the lower film is stretched, and there are foreign bodies on the heating plate, and the plate is injured, so that the foreign bodies are removed and the heating plate is trimmed.

(4) Remove the foreign matter on the heat seal plate and trim the heat seal plate.

(5) Trim the heat-sealing gasket to ensure that the heat-sealing gasket is flat and there is no gap at the same time.

6. Flatness

Phenomenon: the product is curled and wrinkled

Cause:

(1) The design of the upper and lower films is unreasonable.

(2) The tension of the upper and lower membranes does not match.

(3) The sterilization method is not good.

(4) The shape and depth of the molding die are not matched.

(5) the blank is not heat sealed.

Solution:

(1) Design the upper and lower membranes into symmetrical structures to reduce the stress between different structures.

(2) The tension control of the upper and lower films is well matched. Under the condition of ensuring the flatness of the films, the tension should be controlled as small as possible to avoid uneven tension, which will cause the tension of a single film to be large. After sterilization, the films will curl towards the film with large tension.

(3) In the sterilization process, the products should be placed neatly, and there should be no mutual extrusion between products, otherwise there will be discounts, curls and wrinkles.

(4) The die formed by stretching should be similar to the shape of the product as far as possible, and the depth is slightly deeper than the thickness of the product, so as to reduce the problems such as curling and wrinkling caused by the stress after stretching the film.

(5) It is required to heat seal the blank space to increase the strength between the upper and lower films and resist the effect of film stress.