Causes, countermeasures and effects on the quality of BOPP film slitting quality ---
(iv) Effect of film roll tightness on product quality
1. The winding is too tight:
1 fluttering/starting bone: As BOPP film, it is normal for the thickness of the product to fluctuate within a reasonable range. If the reeling tightness is appropriate, this thickness fluctuation will not affect the quality of use, but when the slitting is too tight The thicker layers of the film are stacked together to cause edge thickness or bone swelling, which affects the quality of use. The fluttering or bone formation that is formed by over-tightening is often difficult to find during the slitting process, but after the product has been stored for a period of time, the problem will be highlighted. In addition, there are several types of products with uneven thickness defects that can be easily revealed, such as ultra-transparent tape film, crystal film, heat sealing film, etc., while fluttering and bone-starting phenomenon will cause different quality of all film products. The degree of influence, especially for products that require printing and processing, is particularly prominent.
2 Adhesion: over-tightening of double-sided corona products, anti-corona products and products with less anti-adhesive content will cause adhesion quality problems, and the problem can only be found in the customer's use, the impact is great, and appears Products with adhesion problems can only be disposed of as scrapping, causing large losses to the company.
3 Face wrinkles: Due to the tight winding, the film cushioning performance is degraded. The wrinkles formed by the extrusion of the film on the end face of the product during handling and loading and unloading are difficult to eliminate, forming the end wrinkles and affecting the quality of the product.
4 Pitting: Due to the tightness of the winding, the film near the paper tube is affected by the rough surface of the paper tube, which causes pitting, which affects the quality of the product. The use of the polished paper tube will eliminate the surface of the film and improve it. Start wrinkles).
Slip axis and air shaft of slitting machine--
Sliding gas rising shaft structure characteristics and principle: Slip type gas rising shaft mainly consists of mandrel, airbag, slip sleeve and other parts.
Air enters the inside of the air bag to cause air expansion, pushes each torque group to expand outward, and sets the slip torque value of each torque group according to the inflation pressure, which is convenient for controlling the tension adjustment of each roll of material on the slitter. .
The slip type air rising shaft is mainly used for the striping equipment with high quality requirements and fast speed.
Slip-type air-up shaft technical parameters: slip-type air-up shaft main body outer diameter Φ75mm, action outer diameter Φ78mm, suitable for paper tube Φ76±0.2mm.
Slitting machine parts ---
1. Type of inspection system for the tension and speed of the slitting machine:
1 Tension sensor detection: The tension sensor is installed under the bearing of the tension detecting roller, converts the detected aluminum foil tension into an electrical signal, sends it to the tension adjuster, compares it with the original set tension signal, performs PID calculation, and then inputs The winding motor controller achieves the purpose of controlling the tension and rotation speed of the winding roller.
2Floating roller indirect tension detecting system: a set of floating roller is installed in front of the aluminum foil tracking roller. The position of the floating roller is detected by a potentiometer. The tension control method is to keep the tension constant by keeping the position of the floating roller as constant as possible. .
3 The magnetic powder clutch is used to control the rotational torque of the input winding roller to achieve tension control: the magnetic powder clutch is composed of an active part and a driven part, and is connected to the winding roller through a transmission mechanism such as a universal joint, and the fine ferromagnetic powder is filled in the middle. As a torque transmission medium. A magnetic field is formed by applying a constant current to the exciting coil, and the magnetic powder is magnetized. The magnetized magnetic powder attracts each other to form a chain arrangement. When the active part rotates at a constant speed, the coupling force between the magnetic powders is broken to form a circumferential tangential force, and the product of the tangential force and the radius of the magnetic ring is the driving driven part. The winding torque of the winding realizes the coupling of the output torque from the active part to the driven part in continuous rotation, thereby achieving the purpose of controlling the tension.
4 slitting Unwinding capacity and speed detection system: The magnetic powder tension brake is mainly used to control the unwinding force and speed. The working principle is: the coupling is installed in the magnetic powder brake, and the input parts and output with magnetic coils are installed. component. Below the magnetic coil is an annular groove, the underside of which is an annular rotor or output member. The annular groove is located at the center of the output member and is filled with magnetic powder. When there is excitation current in the magnetic coil, the coil generates magnetic flux to align the magnetic powder in the direction of the magnetic field, thus generating damping between the input member and the output member, and transmitting the torque. If the tension and speed applied to the aluminum foil are increased or decreased, the magnitude of the exciting current can be changed, or the magnitude of the current applied to the coupling coil by the varying amplifier can be effectively controlled.
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