Rubber rollers are used in the rice industry for de-hulling of rice paddy.
Usually the rubber roller wears out in processing of 100 to 150 tons of paddy, depending on variety and the application. This leads to roller change within a couple of days and downtime loss of approximately 30 minutes.
To reduce the change intervals and therefore the downtime for our customers, we are looking for a low-wear rubber material for this application.
There is excessive heat generated during the hulling process by the friction between the paddy surface and rubber. This friction also causes the shear force required for the hulling. This excessive heat doesn’t easily get dissipated due to low thermal conductivity of the rubber and also due to the fact that the same surface repeats the work in the next rotation and doesn’t get opportunity to dissipate the heat completely despite air circulation around the surface.
We need to find a solution to improve the wear rate multiple times either by finding different material that doesn’t wear at high temperature or which dissipates the heat quickly without compromising on ability to grip friction with the paddy surface that is required for the hulling process.

Material properties of the currently used rubber material:
Indicator
Hardness IRHD
Compression set (%)
Tensile Strength (MPa)
Elongation at Break (%)
DIN Abrasion (Volume loss in mm
3
)
90
38.1
16.1
234
168