HDS - Heat Dissipation System
RHL's patented calender roll Heat Dissipation System - helps to avoid overheating and enables higher temperature running
Typical Uses
- Woollen Paper Calender Rolls
- Cop Cotton Calender Rolls
Key Features
- Helps to avoid overheating / burning
- Increases roll life
- Allows increases in speed and / or line pressure
- Promotes even temperature profile
- Improves uniformity of finish
RHL’s Heat Dissipation System is a patented system for reducing the internal and surface temperature of conventional ‘pressed’ calender rolls (‘bowls’).
Calender rolls fitted with the HDS have been proven to operate with surface and internal temperatures typically 15% - 30% lower than equivalent rolls without the HDS. This helps to avoid overheating / burning, increases roll life and allows operation at higher line pressures and speeds.
The HDS System
The Heat Dissipation System comprises a series of thin copper discs fitted at regular intervals (approx every 12mm) within the cover material of the calender roll.
The copper discs contact the roll shaft which is copper plated for improved heat conductivity. The outside diameter of the discs is set below the minimum usable diameter of the roll and the resilience and calendering performance of the roll is unaffected.
To complete the system, the copper plated roll shaft which acts as a ‘heat sink’ for the fibre based cover, is bored through to allow the circulation of cooling water thus removing transferred heat from the centre shaft.
Performance
The Heat Dissipation System enables the dissipation of frictional and process heat generated within the internal fibrous structure of calender roll cover.
In addition, the system has been proven to significantly even out the temperature profile of the roll along its face length.
Tests carried out on HDS Bowls in service indicate a decrease in surface and internal temperature of typically 15% and a temperature profile of maximum +/- 1°C.
