Rewinder mechanical structure and control process ---
As the last process in the papermaking industry, the winder is the fastest running machinery in papermaking machinery. Its speed can reach 1500~1800m/min or even the speed can reach 3000m/min or more. The winder is in the papermaking industry. The important role that can not be ignored, the paper roll from the paper machine must be rewinded by the winder to get the finished paper roll we need, and the quality of the finished paper roll is not only determined by the paper machine, The role of the winder is also of particular importance.
The working principle of the winder is to install the large paper roll produced from the paper machine on the paper exit frame of the winder. In order to maintain a certain tension of the paper web, the brake device must be installed on the paper return frame. A brake motor is installed on the paper exit frame. If the paper breaks during the rewinding process, the brake device can also brake quickly to reduce paper loss. The web is cut to the width we need by the slitting roller, the paper guide roller and the winder slitting mechanism, and then re-rolled into a paper roll according to the required tightness and the diameter of the finished paper roll. The main structural parameters of the winder are the width of the paper roll that can be rewinded, the maximum speed that the rewinding machine can reach, the quality of the finished paper roll, the maximum diameter of the ejecting roll and the roll paper, and the method of cutting the paper.
There are many types of rewinders, and other devices can be equipped in the rewinder as needed to become a joint machine. The rewinder can basically be divided into the following five types: upper paper rewinder, lower paper rewinder, single roll rewinder, special rewinder and thin paper rewinder. Since the research object of this subject is mainly for the lower threading rewinding machine, the introduction and explanation of the double bottom roller lowering paper rewinding machine will be given.
Design and application of constant tension and load distribution control for winder---
2Rewinder control research status at home and abroad
Rewinding machine is an important papermaking machine. It is usually installed behind the paper machine. Its speed should be 2-3 times of the speed of the paper machine, generally 1500-1800m/min, up to 300om/min. When threading, run at a maximum speed of 1:100. In order to ensure continuous paper and loose paper during the rewinding process, the tension of the paper web must be kept constant; in order to ensure the tight and loose quality inside the finished paper, the load distribution of the front and rear bottom roller motors must be performed. Therefore, the main performance requirements of the rewinder for the electric drive system are long-term linear speed, adjustable speed and wide speed range, and fast response.
The control of the early rewinder is mainly based on DC drive, and the DC control system is composed of discrete components or analog regulators to realize the above control functions. Since the transmission of analog signals requires a one-to-one physical connection, the signal changes slowly, which increases the overhead of computer speed and accuracy, and the anti-interference ability of signal transmission is poor, and paper breakage and wrinkling often occur in the production process. So in the mid-to-late 1980s, the analog regulator was replaced by a digital regulator, and the DC digital control system of the winder appeared. This control system is more stable, reliable and suitable for maintenance than the analog system, and is more suitable for interface with the factory computer. In the mid-1990s, most of the newly-invested rewinders in the domestic paper industry used all-digital DC-speed converters produced abroad, and the more famous ones were the 6RA7O series from Siemens and the 590 series DC-speed converters from Continental Transmission.
Due to the DC motor commutator and the brush, under the stable conditions, the design speed of the winder can only reach 1800m/mni, and the accuracy of the digital regulator is still limited to about 0.08% of the maximum speed, which can not meet the high speed paper. The matching requirements of the machine (the speed of the winder should be 2-3 times the speed of the paper machine). In the early 1980s, European and Japanese developed AC variable frequency speed control devices. This technology was successfully introduced to the United States in the mid-1980s and used in rewinders. The biggest advantage of the AC drive is that the AC motor is simple in construction and reliable in operation, and it requires much less maintenance and repair than DC motors.
Belt rewinding machine design and working principle ---
12Paper roll holder
When the paper roll is stopped, the paper roll is fixed at a certain position by the paper roll holder. The paper roll holder prevents slack and lateral movement of the paper roll. It is important to make a joint when making a customer roll. Roll holder on the take-up roll
The paper roll holder on the paper roll includes a spring-loaded plastic roll mounted on the paper cutter frame. When the paper cutter is in or on the middle position, the paper roll holder is placed against the surface of the rear bottom roller.
13 Automatic roll change
The rewinding device removes the paper roll from the winder.
The rewinding device cuts the sheet, pushes the paper roll onto the unloading station and fills in a new core for the rewinding.
The roll change can be started when the roll is decelerated. In the final stage of deceleration, the nipple guardrail and the platen roller rise to a high position. The unloader rises to the position where the paper roll is received. When the winder stops, the paper core clamp opens and rises to rise. The paper cutter is raised from between the paper rolls. The paper feed roller pushes the paper roll to the paper unloading station. At the same time, the paper cutter cuts the paper. The vacuum suction of the rear bottom roller sucks the cut sheet onto the roller. The core loader drops the new core onto the roll. The paper feed roller returns to its original position and the unloading table falls to the middle position. The paper core clip is lowered and closed. The platen roller and the nip guard are lowered. The winder crawls at a speed.
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