Trouble Shooting Of Zipper Bags

- May 10, 2019-

The zipper bag is a kind of composite flexible bag which is often used in life. It has a self-standing zipper bag, a three-side zipper bag, an eight-side flat-bottomed zipper bag and the like, and there are many kinds of patterns. However, the zipper bag is prone to failure. This paper analyzes the top ten faults that are easy to appear in the zipper bag. I hope to help everyone!

IMG_20180703_171955

 


First, the bag is bent


1. The balance between film tension and chain tension is not good.


(1) The tension of the regulating roller is too weak.


(2) The brake of the zipper belt is too tight.


(3) The sliding of the zipper tape is not good.


(4) The groove of the zipper plate is too narrow.


(5) The sliding of the zipper plate is not good.


(6) The film does not slide well at the swash plate/M plate.


2. The temperature of the zipper heat seal is too high.


3. The tension of the rubber roller under the zipper is loose and the tension of the roller is poor.


 IMG_20180714_153250


Second, the zipper belt is poorly sealed locally


1. Foreign matter (polyethylene residue, dust) is mixed in the zipper heat sealing plate.


2. The Teflon surface mounted on the zipper frame is damaged or has foreign matter.


3. The Teflon surface of the zipper plate is damaged or has foreign matter.


4. The zipper plate is partially damaged or deformed.


 


3. The end of the heat seal of the zipper tape is not sealed by heat or the heat seal is extremely weak.


1. The thickness of the zipper tape is not suitable.


2. The position and belt of the zipper heat sealing plate are not aligned.


 


Fourth, the zipper anastomosis welding


1. The temperature of the zipper heat seal is too high.


2. The position of the zipper heat seal is offset and the anastomosis is pressed.


3. The waiting time is too long and is affected by the warm-up.


 


5. Elastic adjustment of the roller is no problem, but there is a deviation between the edges and the pattern of the zipper frame.


1. The position of the zipper plate is too low, the lower film is heat sealed to the lower side, and the cooling plate is rubbed. Or affected by the preheating of the underside heat seal.


2. The rubber roller on the lower side of the zipper does not grip the film well, causing the film to slip.


3. The position of the upper separation roller of the rubber roller on the lower side of the zipper is not set.


4. The tension of the elastic adjustment roller is too small.


 

IMG_20180714_153930

Sixth, the zipper's anastomosis strength is too small


1. The original zipper tape itself has too small anastomosis strength.


2. The thermal cover on the open side/inside pocket side of the zipper strap is reversed.


3. The temperature setting of the zipper heat seal is too high, and the anastomosis is deformed, especially the recess is opened.


4. At the zipper plate, the flow of the film and the angle of the zipper plate are deviated, and the edge of the zipper plate rubs against the anastomosis.


5. The rubber roller is pressed against the anastomosis site.


6. The edge of the rubber roller groove rubs against the anastomosis.


7. When two rows of bags are formed, the film (especially OPP/CPP) shrinks due to heat, and the two-row bag for the center of the zipper plate rubs against the anastomosis.


8. The top cooling plate is too wide and the anastomosis is pressed.


9. The upper and lower gaps of the string of the lower rubber roller are too small, and the zipper anastomosis is pressed too tightly.


 


Seven, in the point heat seal, excessive volumetric pressure


1. The temperature of the longitudinal heat seal is set too high.


2. The longitudinal pressure is too large and the edge of the heat seal is pressed into the rubber table.


3. The rubber table is worn or uneven.


4. The width of the cooling plate (top) is too large and the top heat seal is not pressed.


5. In the Teflon roll of the longitudinal heat seal, a thick Teflon cloth was used to allow the air to be sucked in.


 


Eight, in the transverse heat seal, excessive volumetric pressure


1. When the block heat seal is strengthened, the heat seal plate does not sufficiently press the film.


2. The silicone rubber (especially the upstream side) of the pressure receiving table has a concave shape or uneven surface.


3. The heat-sealing plate and the silicone rubber on the table use coarse-grained Teflon cloth to absorb the air into the grain.


 


Nine, in the pressing part of the zipper, leaving the core or leaking liquid


1. The gap between the hot seals of the zipper is too small.


2. The temperature of the point heat seal of the zipper is set too low.


 


X. Separation of aluminum and ink at point heat sealing and lateral heat sealing


1. The reason for the separation is caused by the difference in the dissolution rate of the PE or CPP of the dissolution layer and the elongation speed of the AL or the ink.


2. The countermeasure is to reduce the running speed and ensure sufficient heat sealing time.


3. Do not pressurize the reinforcement block heat seal.


4. When the block is heat sealed, adjust the gap and melt slowly.


5. The rounded reinforcing block heat seals the edge portion of the sheet so that the edge of the AL or ink expansion is not cut.


6. Try to use multiple sections of reinforcement block heat sealing.


7. Using a heat-sealing plate, the coarse-grained Teflon cloth for the cooling plate is absorbed into the mesh of the glass fiber.