The lagging can be affixed to the DRUM PULLEY by vulcanizing to the DRUM......or by interlocking steel edged strips across the width of the DRUM.....user preference.

Others can explain the pros and cons of each much better than me.

Durometer of the rubber and pattern on the LAGGING is important also......Herringbone is the most common we use time and time again....DUROMETER.....i am not sure of. ■

I think George's response relates to pulley's not idlers.

Rubber impact discs are designed to absorb and deflect impact at a loading point. The rubber discs are friction fitted to the idler shell and usually held in by a mechanical constraint. The quality of the rubber used is extremely important as poor quality means they will not absorb or deflect the load and thus the belt may get damaged. The various quality idler manufacturer's around the world have very specific specifications based on their experiences over time. Ask for further details from them or check out their websites and see what is on them. It is a long time since I have specifically looked at this issue but I would expect if you need more the best source is the idler manufacturer.

Colin Benjamin ■

Dear Puneet,

When we look at the kind of rubbers, there will be SBR, NR, NBR and etc. The rubber for impact must has ozone resistance, abrasion resistance, compression resistance and a good elongation. In my opinion, this can get from mixture of SBR and NR where SBR has a good ozone resistance and abrasion resistance, NR has a good elongation meaning the rubber not easy to break if any strecth.

The rubber is mecahnically fitted to the roll pipe, the shape depends on the manufacturer.

I summarize that rubber ring for impact must has a good compressive strength, tensile, elongation (at break), hardness, aging (related to the life time) and swelling.

The properties can be found from its vulcanizate by testing/examination.

Rgds,

Endri ■