Machining and Grinding and Coating of Dryer Roll
1. To remove hard chrome we need to do by machining (Turning) Thickness of chrome to remove is approx. 0.5 mm.
2. Machining frame was installed on big and heavy and strong H-beam size 10”x10” in order to prevent vibration during machining
3. Grinding is done after machining to make more smoother surface grinding is done by abrasive grinding belt. To get roughness 0.8 – 1.2 Ra
4. Grit blasting is done to create good surface bonding of Tung stain car bide
5. Tung stain car bide coating is done by HVOF Gun. To get surface coating 80 µ ± 10 µ.
6. Coating with dream coat. Non stick top coat “Dream coat” will applied on top of Tung stain car bide surface. Thickness of coating is 20 µm
7. Curing of dream coat is done by heater to increase temperature to 160˚ in exactly period of time. As well as cooling down of temperature
8. Recommended Doctor Blade is fiber glass. But before start up of machining. Doctor blade lift time is rely short so better to moue running of dryer with doctor bland for a white such as 12 hr. until blade lift time is longer.
9. Roll – after grinding and polishing
- Straightness ± 0.1 mm.
- Roughness 0.8 – 1.2 µ Ra
- Roundness less than 0.10 mm