A lot of customers in the process of using hot melt adhesive, may encounter some such as glue line early curing, nozzle or blockage in a rubber hose, hot melt adhesive, hot melt adhesive gel, carbide bubble of hot melt adhesive, hot melt adhesive wiredrawing, our company according to his many years of industry experience, has carried on the answers to these questions, hope to be of help!

1, glue line curing in advance

Often because the amount of glue is too small, or the temperature setting is not appropriate

Consequences: Out of the box or fake bonding

2, curing speed is too slow

It is often because the amount of glue is too much, the temperature/pump pressure is too high, the nozzle diameter is too large, the pressure of the packaging machine is not uniform and other reasons.

Consequences: open box/false bonding/glue cost increases

3. The nozzle or hose is blocked

Cause: hot melt glue is too sticky; To produce carbides or gels; There are foreign bodies in the rubber cylinder

Solution:

Increase the temperature or another low viscosity hot melt adhesive

(2) cleaning the glue spraying system or reduce the temperature and change the glue

(3) cleaning rubber cylinder, standardized glue

4, drop, flow glue

Reason: the nozzle is dirty and damaged; There are foreign bodies and wear in the nozzle valve; Solenoid valve installation loose, air leakage; Air pressure instability, underpressure

Solution:

(1) cleaning nozzle (2) maintenance or replacement (3) reinstallation confirmation (4) reset, check to meet the requirements

5, hot melt glue splash

Reason: high rubber pressure; The temperature is too high; Too low viscosity; Incorrect nozzle position

Solution:

(1) Adjust the pressure of the rubber pump of the rubber machine to reduce the pressure;

② reduce the temperature;

(3) reduce the temperature, reduce the distance between the spray gun and the object;

④ Change the nozzle position

6, hot melt adhesive carbonization

Reason: the rubber cylinder temperature is too high; Carbonization on the side wall of the rubber cylinder; Oxidation of hot melt adhesive; Large temperature control range, out of control

Solution:

(1) The rubber cylinder is filled with rubber, and the rubber is added according to the technical documents.

The upper cover of the rubber cylinder;

③ maintenance or replacement;

④ Reduce the temperature

7, hot melt gel

Reason: two kinds of insoluble glue mixed; Overheating; Hot melt adhesive is unstable

Solution:

(1) cleaning rubber cylinder, standardized rubber change, find suppliers;

(2) reduce the temperature, clean the rubber cylinder, find suppliers;

Clean the rubber cylinder and find suppliers

8. There are bubbles in the hot melt adhesive

Reason: hot melt glue vacuum is not done well; The manufacturing process does not match the packaging

Solution: contact the supplier and change the glue

9. Unstable spray pattern

Cause: Light sensing objects and controls are not well adjusted; The setting temperature is not accurate; The nozzle is not clean and damaged

Solution:

① readjust;

(2) Contact suppliers to set the correct temperature;

③ cleaning, maintenance and replacement

10, hot melt glue wire drawing

Reason: the operating temperature is too low; The glue temperature in the tank is too low; The jet time does not match the speed of the carton; Nozzle switch wear; The old glue has outlived its useful life in the rubber tank

Solution:

(1) raise the temperature (note: the temperature is too high will affect the thermal stability of the glue);

② pre-heating;

③ adjust the machine;

(4) clean and repair the nozzle;

Clean the system and add new hot melt adhesive

11, hot melt glue can not flow evenly from the nozzle (spray glue)

Reason: nozzle blockage; Insufficient air pressure in multiple nozzles; Operating temperature is too low

Solution:

(1) cleaning, maintenance, replacement;

Check the quality of hot melt adhesive, carbonization, impurities, glue change;

Check the pressure stability of the spray gun, check the nozzle and sprinkler head;

④ Increase the temperature and contact the supplier to correct heating

12. The hot glue is smoking

Cause: the operating temperature is too high; Temperature control out of control; Hot melt adhesive has poor thermal stability

Solution:

(1) reduce the temperature, find suppliers;

Replace the out-of-control components and find the equipment supplier;

(3) standardized glue change, find suppliers

13. Bad bonding

The reason:

(1) the amount of glue is not enough or the operating temperature is low and the hot melt adhesive is mainly on the side of the substrate;

(2) because the hot melt adhesive is then affected in the semi-molten state, both sides of the substrate have glue, but there are many curing fine "feet";

(3) the bonded surface is not in contact or contact is not good, the hot melt adhesive surface is smooth;

The bonding is easy to be separated. Usually because of the poor choice of adhesive.

Solution:

(1) increase coating thickness or increase temperature;

(2) check whether the pressure is good, reduce the operating temperature, or use a fast curing adhesive;

Adjust the pressure to ensure that the hot melt adhesive cooling process of the substrate contact is good;

14, hot melt adhesive penetration is not good

Reason: the temperature is too low; The adhesive layer is too thin; Paper board coated (with wax or oil, for example)

Solution:

① raise the temperature;

(2) improve the temperature and pipeline pressure, increase the amount of glue;

(3) can try different properties of hot melt adhesive, or on the surface of the cardboard treatment

· Notes for Hot Melt Adhesive

1, do not overheat the colloid, without the permission of the supplier, shall not heat more than 180℃;

2, can not mix different kinds of hot melt adhesive;

3. Clean up the environment around the hot melt glue machine at any time and keep it clean and sanitary;

4. Glove and mask or glasses should be worn when adding hot melt adhesive or cleaning hot melt adhesive, and be careful when adding, so as not to splash hot melt adhesive and cause scald;

5, timing feeding, in order to maintain the liquid level height. The liquid level is too low and it is easy to splash when feeding, which leads to scald.

6. A bucket of cold water is prepared next to the hot melt glue machine for personnel to soak in the unfortunate scald, so as to reduce the injury;

7. As far as possible, the hot melt adhesive and its peripheral equipment are placed below the eye level;

8, if the position of the hot melt glue machine is too high, the platform should be added to facilitate the operation of personnel.