Common fault problems of wet wipes packaging machine

The wet wipes packaging machinery has been used for a long time, especially in the case of continuous work and overload, some electrical and mechanical faults are prone to occur, such as: the sealing is not strong, the machine stops and goes, the fuse is blown when starting, and the ” “Squeak”, uncontrollable temperature, deformation and bending of the finished bag at the sealing, bubbles or irregular marks at the imprint of the sealing knife, etc.

Combined with the actual use experience of the packaging machine, the causes of several faults are analyzed, the corresponding solutions are proposed, and the maintenance problems of the continuous sealing machine are expounded, hoping to be helpful to the enterprises and individuals who use the continuous sealing machine.

1. Inadequate sealing Insufficient sealing is one of the common faults of continuous sealing machines. Insufficient sealing has three meanings:

①The seal of the packaging bag cannot be sealed;

②Under the pressure of the sealing knife, although the bag mouth is sealed, but a little force is squeezed or peeled off, the seal will crack again;

③When the peeling test is performed on the sealing part, there is a phenomenon that half of the sealing is firm and half is separated. The sealing quality of such a packaging bag is still unqualified, because the contents are easily leaked during storage and transportation. This situation often occurs when the composite lining is OPP and blow-molded PE.

The main reasons for the first failure are as follows.

(1) The heat-sealing temperature is not enough. Under normal circumstances, the composite bag with OPP as the lining, when the total thickness of the bag is 80-90 μm, the heat-sealing temperature should reach 170-180 ℃; the composite bag with PE as the lining is made When the total thickness of the bag is 85-100μm, the temperature should be controlled at 180-200°C. As long as the overall thickness of the bag is increased, the heat sealing temperature must be increased accordingly.

(2) The heat sealing speed is too fast. The failure to seal the mouth is also related to the speed of the sealing machine. If the speed is too fast, the sealing part will be transported by the traction roller to the cold pressing place for cooling treatment before it can be heated, which will naturally fail to meet the requirements of heat sealing quality.

(3) The pressure of the cold-pressed rubber wheel is not suitable. There are two cold-pressed rubber wheels on the top and bottom. The pressure between them should be moderate. When adjusting the pressure, only the spring can be clamped.

(4) There is a problem with the quality of the heat-sealing film. It is also related to the quality of the heat-sealing film. If the corona treatment of the composite lining is not uniform, the effect is not good, and it happens to appear at the seal, and it must not be sealed. This situation is rare, but when it occurs, the product is bound to be scrapped. Therefore, in the color printing and packaging industry, the next process supervises the previous process. Once a quality problem is found, the cause must be analyzed and solved in time. If there is moisture or dirt on the seal, it will also cause the seal to be weak. In short, to solve the first problem of poor sealing, generally, the heat sealing temperature can be appropriately increased, then the heat sealing speed can be reduced, and the pressure of the cold pressing rubber wheel can be increased at the same time.

The main reasons for the second type of poor sealing failure are as follows.

(1) Insufficient heat-sealing temperature It is only necessary to increase the heat-sealing temperature appropriately to solve the problem.

(2) The blade surface of the heat-sealing knife is not flat enough. The heat-sealing knife is divided into upper and lower parts, and the thermoelectric coupling is usually installed in it to sense the transfer of temperature. There are three screws on the heat sealing knife. The middle screw is used to support and reinforce the blade. The other two screws are equipped with pressure springs and gaskets, which are mainly used to adjust the pressure of the heat sealing knife. The upper and lower blades have two springs each. . The main reason for the uneven blade surface of the heat sealing knife is that the middle screw is installed obliquely and not horizontally; or the pressure spring of the upper heat sealing knife is unevenly pressed. The solution is to recalibrate the position of the intermediate screw so that it is level. If the upper and lower heat sealing knives are unbalanced, it should be realized by adjusting the pressure spring, and the adjustment can be moderate. When the spring is withdrawn, the heat sealing knife will fall down; when the spring of the lower blade is tightened upward, the heat sealing knife will move upward.

(3) Uneven pressure of the cold-pressed rubber wheel Uneven pressure of the cold-pressed rubber wheel will also cause this kind of failure of the sealing, and the solution is similar to the first case.

There are two main reasons for the third type of poor sealing failure.

(1) Uneven pressure of heat-sealing knife or uneven pressure of cold-pressing knife The adjustment on the heat-sealing knife and the cold-pressing knife is exactly the same.

(2) The blade surface of the heat sealing knife is not flat enough. Refer to the corresponding solution for the second type of sealing failure.

2. The fuse is blown. The main function of the sealing machine motor is to drive the gearbox and gear transmission of various components. Sometimes the sealing machine will make a “squeak” sound as soon as it is started, and it will not work normally, and even the fuse on the live line will blow. To eliminate this fault, first check whether the power supply is normal, then cut off the power supply, use the resistance gear to test whether the switch is damaged, and carefully check whether the circuit and the motor are short-circuited. Usually, when the motor is short-circuited, the winding is burned or the wire is broken, the fuse is blown as soon as the sealing machine is started. Another reason for this failure is that the size of the fuse is too small, and the problem can be solved by increasing its size accordingly.

3. There is a “squeak” sound during operation. The fault occurs during the operation of the sealing machine. The “squeak” sound often occurs suddenly, and then the sealing speed is uneven. Appearance Quality. Works fine occasionally, but capriciously.

This phenomenon is mostly due to mechanical damage or severe wear and poor lubrication. First follow the sound to find the fault location. Disassemble the back protection plate and find that the “squeak” sound is from the gearbox. Remove the fixing screws one by one, and find that the grease in the gearbox has been dried and the gears are bright, which indicates that the cause of the failure is Lack of oil. After mixing the same type of oil and grease, add it to the gearbox, and tighten the screws to restore, the “squeak” sound disappears after starting the machine, and the sealing is normal.

In addition, if the joints of the high-temperature belt are loose, severely worn, unclean, with dirt on the surface, and they are not synchronized with the traction pulley during operation, sometimes a “squeak” sound will be heard. The solution is to replace the high temperature belt of the same specification. Replacing the high temperature comes with certain tricks. First, compress the spring of the pressure wheel by hand, then place one end of the high temperature belt on the rubber wheel, and hold the other end against the other rubber wheel by hand. Movement inertia, the high temperature belt is automatically installed. Sometimes the “squeak” sound is also issued by the DC parallel excitation motor. It may be caused by lack of oil in the motor bearing. If this is the case, it should be removed and lubricated to eliminate the sound.

4. The sealing temperature is out of control. The fault is manifested in the failure of the thermometer display, the temperature cannot be controlled, the heat sealing temperature is not constant, the sealing part is either burnt, or the sealing is not strong, the sealing is deformed, and it is ugly. The main reason for this failure is that the thermometer is broken and must be repaired; in addition, the thermocouple may also be broken and cannot transmit the sensed temperature to the thermometer normally. Just replace it with a thermocouple of the same model and specification. The mechanical reason is that the heat sealing pressure is uneven, as long as the pressure spring of the heat sealing knife is adjusted to make the pressure consistent. At the same time, the pressure contact surface of the heat sealing knife should be kept clean and free of dirt. Another reason is that the heat sealing quality of the composite material itself is not good, and the heat sealing coefficient changes, resulting in inconsistent temperatures.

5. The sealing machine stops and goes. We have encountered the failure of the sealing machine that stops and goes and the speed is inconsistent during production. We disassembled the panel on the back of the sealing machine and found that the connection between the shaft of the motor and the gearbox has appeared. Falling off, relaxation phenomenon. Re-tighten the screws to make them all fit and the problem is solved. In addition, the main motor is operated by the contact of carbon brushes. If the carbon brushes are severely worn, not completely in contact with the slip ring, or the friction is not good, the sealing machine will also stop and go. Brushing can solve the problem.

6. Air bubbles and irregular marks appear at the seal. This fault is also relatively common. Although it will not cause leakage of the packaging, it affects the aesthetics of the packaging and damages the image of the product. There are two main reasons for this failure. (1) After the equipment has been used for a long time, the high temperature belt has adhered to dust and plastic chips and other dirt, causing the high temperature belt to be uneven and uneven, making the sealing unevenly heated, and air bubbles appear after being pressed by the cold pressing wheel. The fault can be solved by cleaning or replacing the high temperature belt. The high temperature belt is generally 1.5cm wide and about 22μm thick. If it cannot be washed off after sticking to the dirt, it has to be scrapped. (2) There are irregularly arranged concave and convex marks on the cold-pressed rubber wheel, which are directly reflected on the packaging, so that more obvious marks appear at the seal. In order to ensure the appearance of the packaging bag, it is best to replace the cold-pressed rubber wheel.

7. Problems that should be paid attention to in the maintenance of wet wipes packaging machine equipment (1) The sealing machine should be placed in a ventilated and dry place, and the room temperature should generally be maintained at about 25 °C. (2) Every 48 hours of operation, 6# oil should be added to all moving parts, mainly in gears, bearings and gearboxes. (3) Dust should be removed regularly to keep the whole machine clean. When not in use, it is best to unplug the power supply and cover it with a cloth. (4) If the running time is too long, the cooling fan should be turned on before shutting down, and then shut down after the temperature drops, because it will be shut down without cooling, and the high temperature belt will be easily damaged. (5) The high temperature zone should be cleaned regularly to ensure the sealing quality. (6) Seriously worn parts should be replaced in time to prolong the life of the whole machine.