Common problems of slitting machine and interpretation of tool usage classification

- Jan 15, 2021-

Common problems of slitting machine and interpretation of tool usage classification


In our daily slitting machine die-cutting production process, we often encounter the problem of material classification and slitting. Under normal circumstances, if the scale of die-cutting processing is not large, we will choose to cut the material directly by the supplier when the material is received. But in general, large-scale manufacturers will directly equip slitting equipment. So what are the problems in the actual slitting process? What measures should we take to deal with these problems? Below, the editor will explain and analyze some common problems encountered in the daily cutting process;



The slitting method of common die cutting materials


(1) Oblique cutting: According to the material feeding requirements, the feed direction of the tool is adjusted so that the feed direction is not completely perpendicular to the material roll diameter;


(2) Cutting: The cutter is fed vertically, and the wide coil is cut into multiple rolls of narrow specifications;


(3) Single-speed feed: refers to feed the material or tool at the speed of any station, and the other station keeps the driven feed;


(4) Dual-speed feed: refers to the cutting of materials by feeding materials or tools at opposite speeds.


       Manufacture and purchase of qualified slitting equipment must not only meet these technical indicators, but also must consider the following two factors: operating efficiency, which mainly includes the working speed of the equipment, stability and the difficulty of machine operation, etc.; economic performance refers to equipment The scope of application of the material, the processing limit size, and the price of the equipment, energy consumption, etc.




About the selection and use of slitting tools


(1) White steel knife, also known as high-speed steel knife, this kind of knife has good toughness and high cutting efficiency, but the cutting sharpness is not good. Generally, when using this kind of tool, it is necessary to adjust the speed appropriately to compensate for the unsharp phenomenon that may be caused during the cutting process. This kind of blade is mainly used for cutting high hardness materials such as PET and PE materials. The price is relatively cheap, more practical, and it is a common tool.





(2) Tungsten steel knives, which are brittle and sharp, and are generally used for slitting soft materials such as double-sided tape. The cutting precision of the cutter is good, and there are fewer burrs and silk edges during the cutting process. However, the tool is prone to chipping for relatively hard materials. In addition, the cost of the tool is relatively expensive, and the general manufacturers only use it to cut relatively soft materials such as tape, PE film, and masking paper.


Note: The problem of material edge mentioned in the article is largely because the material is not tightly wound during the winding process, and the material dislocation due to the speed of the slitting process is caused by the material. It is not all equipment and cutters. the reason. The manufacturer should pay attention to inspection during use.




Process requirements of common slitting machines


(1) The self-adhesive slitting machine should stop the fixed length slitting processing of the entire roll or the entire original material, such as plastic packaging materials, packaging cartons, steel plates, films, leather, wood chips, etc. Fixed length slitting control.


(2) The control of the fixed-length slitting machine is divided into two types: static and dynamic slitting: when the set length is reached, the machine stops accurately, then the static slitting is processed, and the operation is restarted after slitting; when the set length is reached, The slitting signal is issued without stopping the machine, and the slitting machine dynamically slits and processes during the movement of the material.


(3) The most important performance index of the fixed-length slitting machine is the slitting accuracy, and the length of the waste is good.


(4) The length of the self-adhesive slitting machine can be set continuously. If there is an error in the actual slitting length, it is easy to stop the calibration by setting the parameters.




Problems encountered in the work of slitting machine and solutions


       The width of the base paper is generally 3-5mm larger than the size marked on it. Under special conditions, it will jump out of this range. If the size of the base paper is 1185mm, we adjust the knife to 1190. In the case that the base paper may be larger than 1190, the paper tray at the edge There will be glitches. In this case, stop the machine and loosen the knives for a while, and then tighten the knives.


Why does the paper tray on the right side of the slit protrude for a while?


(1) When the machine starts to run, the strip of paper at the edge is not tightened, and the paper strip can be properly inserted when the machine starts to cut the strip to avoid this situation.


(2) The inner diameter of the paper core added to the paper core is too large, so that the paper core cannot be locked after the air shaft expands, and the paper core slips during rotation, causing deviation. The solution is to check the paper core when the paper core is sleeved on the intake shaft. The size of the inner diameter.




Names and functions of common components in equipment


       The pneumatic parts and components used by the slitting machine include: pneumatic cylinder, speed regulating valve, shuttle valve, pressure reducing valve, solenoid valve, manual valve, oil mist separator, water mist separator, etc.


(1) Speed control valve is also called throttle valve: a pneumatic element that controls the speed of the cylinder by adjusting the gas flow. Generally, it is not easy to be damaged. If it is damaged, it may be caused by the valve body rupture or twisting damage.


(2) Shuttle valve: The shuttle valve is divided into two-position one-way and one-position one. There are three air inlets and outlets. When a relatively large pressure inlet is sensed, the actuation outlet pressure is displayed as a large pressure outlet. The air inlet to the valve is closed. This valve is usually used when the decoiler brakes and the tension produces different pressures acting on the output port. Generally, a single-entry check valve structure is used.


(3) Pressure reducing valve: The pressure reducing valve is a device that partially reduces the system pressure or branch pressure in the system. The pressure is achieved by adjusting the knob. Its structure is composed of pressure gauge, valve body, spring, and reducing pressure. Composed of diaphragm, usually when the pressure reducing valve fails or leaks, it is caused by diaphragm damage.


(4) Pneumatic cylinder: It is a power acting device, consisting of a pneumatic cylinder, electroplated shaft core, front and rear cover plates, pistons and air seals. The most prone to wear is the air seal, such as O type, Y type, V type, etc. When in use, if it is noticed that its actuation ability has decreased, it may be caused by damage to the air seal (detection method: remove the air pipe at one end of the cylinder and supply air to the other end. If there is gas leaking from the nozzle, it is determined as Caused by poor sealing). It can be removed to check whether the air seal is damaged or other cylinder defects.


(5) Solenoid valve: It is a functional valve that uses the solenoid to generate electromagnetic force to push the spool to complete the selection of gas passage channels when the solenoid is energized. Our commonly used valves are two-position three-way, two-position five-way, three-position five-way, etc. The position mentioned here means that the valve body has a way to control the airflow channel, that is, the cylinder's movement direction is different at a certain "position", and "pass" refers to the number of gas inlets and outlets in the circuit.


(6) Oil mist triple: when the gas passes through, the lubricating oil stored in the oil cup is atomized and then enters the actuating cylinder together with the gas for lubrication. At the same time, the water in the gas can be separated, and A device that can control the outlet air pressure through a pressure regulating valve. Its composition structure includes: pressure regulating valve, oil mist device, water mist separator, altogether called three-piece air pressure.