Web Guiding for Slitter Rewinder System

Web guiding system are broadly used in slitter rewinder equipments to automatically guide various types of materials such as plastic, paper, foil, rubber, etc. Generally, web guide consists of sensor, controller, actuator and guide device. The sensor is used to monitor the web position for lateral tracking, and transmit signal to the controller. If the actual position measured by the controller is away from target position, the guiding device moved by the actuator will shift the web to correct position whenever. A little off-tracking is okay, but too much lateral shifting will cause big problems.

Off-tracking problems in slitting and rewinding process

1) The influence of mechanical accuracy, temperature or humidity, may result in the shifting problems of materials.
2) Mechanical structure error or web’s own reason may result in the periodic and irregular position error.
3) Bad accuracy of unwinder and rewinder may cause unwinding and rewinding deviation.
4) Errors caused by material splicing in production.

Determine the right type of slitter guide

In order to find a winning hand in web guiding, you should determine where you need lateral position accuracy and further to choose the proper web guide which can best meet your needs. There are four types of web position control systems including unwind guide, displacement guide, steering guide and rewind guide, they can play a role in three possible web guide locations as below:

1) Unwinding guide system. During slitting, good control of the unwinding process is very important. Input guiding system provides accurate edge alignment for unwinding rolls of material at the beginning stage. The incoming material should be constantly aligned on the transport roller into the slitting and rewinding process. An unwind guide has the simplest web path, and require lateral shifting of the unwinding roll. Displacement guide immediately downstream of the unwind stand adds to the web path complexity, and guide the web with a smaller actuator without shifting the winding roll.

2) Intermediate guiding system. As the web moves through a process, it have many intermediate web-to-process alignment requirements such as avoiding contact with slots or sidewalls and entering centered to slitting processes. Displacement guide with its easy setup and compact design should be the first choice for intermediate guiding. Steering guide is best used to control the position of a long span.

3) Rewinding guide system. Rewinding guide system doesn’t actually guide the web, but instead moves the equipment to chase the web which must be centered or aligned to the winding core. A winder guide is the simplest option, shifted to catch the wandering web. Just like using at unwinding, a displacement guide immediately upstream of the winder adds to the web-path complexity but will guide the web with a smaller actuator without shifting the winding roll.

Leap have been successfully manufacturing all types of top-quality slitter rewinder machine with web guiding system, and available in stock of various web guides with international standards. Our experienced engineers can also help you to choose the best web guiding solutiong for your specific slitting applications.