Nomex®
Nomex® calender rolls are the optimum performance solution for very high temperature Supercalendering applications.
Typical Uses
- Glassine
- Candy Wrap
- Release Papers
- Condensor Papers
Key Features
- Withstands very high temperature calendering conditions
- Good marking resistance due to high modulus of elasticity
- Reduced maintenance and very long service life
Nomex® is a man-made fibre based material suited to very high temperature calendering conditions. Outstanding temperature resistance, excellent resistance to surface damage and high nip loads ensure minimum maintenance and a very long service life.
DuPont Approved
“DuPont certify that they consider RHL to be fully technically capable to manufacture filled rolls with Nomex® . We therefore recommend this company as an excellent source for long lasting Nomex® calender rolls.”
DuPont de Nemours Int. SA, Geneva, Switzerland
Construction
Nomex® is a ‘man-made’ fibre based material. The material has a rigid and regular (meta-aramid) molecular structure. Because of the strong structural linkages, Nomex fibres are both chemically and thermally very stable and will not flow or melt even above 350°C. For this reason Nomex is suited to high temperature calendering where alternative roll cover materials would quickly break down.
This unique constuction also gives Nomex® excellent marking resistance. Marking resistance and recovery is closely related to Modulus of Elasticity (the ability of the material to rebound to its original shape after being dented). The Nomex® structure has a high modulus of elasticity, which is maintained at elevated temperatures.
Operational Benefits
- Outstanding temperature resistance (enabling the heated steel roll to be run up to 360°C)
- Excellent mark resistance due to high modulus of elasticity
- Outstanding service life. Typically 5-10x lifetime of normal cotton paper filled roll, leading to lower operating costs
- Nomex can withstand high nip loads up to 450kN/m
- Nomex can be filled on the same roll shafts used for conventional cotton fibre cover materials
- Lower risk in case of accidental surface damage (compared to polymer rolls) due to cover thickness. Nomex® rolls have a regrind depth of typically 60-70mm compared to typically 6mm for Polymer rolls
Quality Benefits
- Positive gloss production (similar to cotton paper filled rolls)
- Excellent smoothing effect
- Excellent densification of the calendered product
RHL produce complete new Nomex® rolls or can refill existing filled rolls with Nomex® material. Nomex can be resurfaced using standard equipment such as diamond tool, abrasive belt or stone grinding.
Performance
| Typical Material Hardness | Max. Speed | Max. Linear Pressure | Max. Roll Surface Temp.* | |
|---|---|---|---|---|
| Nomex® | 87°Shore D | 900m/min | 450kN/m | 200°C |
