Manual Wire Stretching for Paper Machines

An optimal wire tension is essential for the efficient operation of the wire part in a paper machine (PM). Insufficient wire tension can lead to driving roll slippage, abnormal wear on the wire, driving roll, and suction couch roll. To maintain optimal wire performance and compensate for wire extension during operation, manual wire stretching equipment is provided in two modifications: top and bottom.

Design Features

Top and Bottom Modifications:

• Structure: The equipment consists of four consoles mounted on beams or basement rails.
• Consoles: Two consoles are equipped with hinged levers for fixing a guide roll, doctor, and shower pipe. The other two consoles house worm gearboxes hinged and coupled with the levers by motion screws.
• Gearboxes: Linked by a driving shaft, with a pneumatic motor installed on the drive side.

Control Mechanisms

• Basic Stretching: Without scanning the tension in the wire or felt.
• Optional Tension Control: The device can be equipped with a scanner and automatic tension control, using tensometric scanning sleeves under one of the guide rolls and a relevant control system.

Stretching Control:

• Manual: Controlled by a pneumatic distributor.
• Automatic: Controlled by a control board or control system.

Main Parts

1. Consoles: Provide structural support.
2. Worm Gearboxes with Pneumatic Motor: Facilitate motion and stretching.
3. Levers: Connected to consoles and guide roll.
4. Connecting Shaft: Links gearboxes for synchronized movement.

Accessories

• Pneumatic Distributor/Electric Push Buttons: For control operations.

Material

• Made of stainless steel.
• Available in three standard sizes for bearing pitches:
  • Up to 3,100 mm
  • Up to 5,250 mm
  • Up to 7,500 mm

Scope of Delivery

• Complete machine according to main parts description.
• Optional accessories available.

Bottom Wire Stretching System:

• Importance: Critical during the first days of new wire operation to ensure optimal tension and gradual settling.
• Sensor: Controls optimal tension recommended by the wire supplier.

Design:

• Consists of two welded consoles mounted on basement rails.
• Both consoles have hinged levers for fixing a guide roll, doctor, and shower pipe.
• Pins connect consoles to levers, linked by a connecting pipe for coordinated motion.
• Motion induced by pneumatic bellows of different sizes.

Main Parts

1. Consoles and Levers: Provide structure and motion.
2. Connecting Pipe: Ensures synchronized lever movement.
3. Pneumatic Bellows: Provide motion.

Material

• Made of stainless steel.
• Available in two standard sizes for bearing pitches:
  • Up to 3,100 mm with one pneumatic bellow.
  • Up to 5,250 mm with two pneumatic bellows.

Accessories

• Control Box/Automatic Unit: For control and monitoring.
• Air Distribution with Proportional Valve: For connection to the automatic unit.
• Tension Sensor: Monitors and controls tension.

Scope of Delivery

• Complete machine according to main parts description.
• Optional accessories available.

Stretching Control Options

1. Manual Control: Pneumatic bellows regulated by a valve and chart on the control box, with lever positions indicated by a pointer on a scale.
2. Automatic Control: Lever position sensor, tension sensor, and programmable automatic unit. The automatic unit controls air supply to pneumatic bellows via a proportional valve, maintaining tension according to set parameters.

Advantages

• Simple Operation: User-friendly and easy to manage.
• Reliable and Safe Operation: Ensures consistent performance and safety.
• Longer Service Life of Wire: Enhances the durability and efficiency of the wire.

This comprehensive manual wire stretching system ensures optimal tension, extending the service life of the wire and enhancing the efficiency of the paper machine’s wire part.