Main factors affecting tension stability：
(1) The change of the speed of the machine will inevitably cause the change of the tension of the whole machine.
(2) During the process of collecting and unwinding, the winding and unwinding diameters of the slitting machine are constantly changing, and the change of the diameter will inevitably cause the change of the material tension. When the unwinding torque is constant, the diameter is reduced and the tension is increased. The winding is reversed. If the winding torque is constant, the tension will decrease as the winding diameter increases. This is the main factor that causes the change in material tension during operation.
(3) The change in the tightness of the raw material roll will also cause a change in the tension of the whole machine.
(4) The unevenness of the material of the raw material is cut. If the material elasticity fluctuates, the material thickness changes along the width and length direction, the mass of the material roll is eccentric, and the temperature and humidity of the production environment change, which also affects the tension fluctuation of the whole machine.
(5) The various transmission mechanisms (such as guide rollers, floating rollers, flattening rollers, etc.) of the slitting machine have factors such as imbalance and unstable air pressure.
Causes, countermeasures and effects on the quality of BOPP film slitting quality ---
(2) The purpose, method and characteristics of hardness testing
3. Method for detecting film roll hardness
1 selection of testing equipment
There are various instruments for detecting the hardness of an object, but so far there has not been a hardness tester that professionally detects the hardness of a film roll. Due to the large difference in surface hardness between various objects and the variety of hardness testers, it is important to select a hardness tester that can effectively reflect the tightness of the film roll. After screening and comparison, our company has determined the "A-type rubber hardness tester" for detecting the surface hardness of rubber products as an auxiliary instrument for detecting the tightness of the film roll.
2 detection instrument correction
Since the "A type rubber hardness tester" is not a special test instrument for the film roll, in order to improve the detection accuracy of the instrument, we have modified the structure of the hardness tester according to the characteristics of the film, and increased the presser area by 5 times.
3 detection methods a.
Before the test, the pointer of the hardness tester should be in the free state and point to the zero position. When pressing the hardness tester on the glass plate, the pointer should be 100 degrees (the end face of the press pin and the bottom of the foot are in close contact with the glass). If the zero position and the 100 degree are not indicated, the needle can be pressed slightly several times, if not When referring to zero and 100 degrees, it cannot be used. The hardness tester to be confirmed can be used again if it meets the requirements for use. b.
When testing the hardness, put the hardness tester on the side of the film product, take the left, middle and right positions, at least 40mm from the edge of the film roll, and firmly press the end of the hardness tester with both hands, so that the pressure pin is pressed vertically. The sample is read within 1 s until the pressure is fully contacted with the sample, and the average is taken and recorded.
Reasons, countermeasures and effects of BOPP film slitting quality ---
2. The causes and countermeasures of multilateralism:
(1) The mother roll is seriously deviated, wrinkled or uneven in thickness. When the film runs to the sipe roll, it does not stick to the roller and appears multilateral. It is necessary to improve the quality of film production.
(2) Due to the looseness of the parent roll, the floating roller in the slitting process fails to compensate for the slack in the mother roll in time to cause multilateral occurrence. At this time, it is necessary to accelerate to cope with the problem.
(2) The film roll is not effectively adjusted for the bending roll or the high and low roll or the pull wheel, and the flatness of the film during the slitting process must be improved by effective adjustment;
(3) The blade material does not meet the requirements for use, and the texture is too soft or the friction is deformed by heat. Replace the qualified blade;
(4) Poor cutting control, such as too fast slitting speed, slitting speed and poor sheet/pressure setting. Reasonable adjustment.
(5) The process of slitting due to the loss of sand skin can also cause wrinkles and a multilateral phenomenon.
(6) If the unwinding tension is too small, it will also cause multilateral phenomena.
Zhengzhou EAST IMPORT AND EXPORT co., ltd . ( a goulian group of company) a manufacturer and exporter for all kind of packaging machinery , like bopp tape coating machines, bopp tape slitting machines. Bopp tape core cutter, bopp tape core loader etc