Since the introduction of the first SST idler in 2002, FMC Technologies has continued to focus on the importance of bearings in idler roll design. As a result, the SST II features a new, proprietary bearing developed exclusively for the [Link belt bearings]  D7000 SST II idlers. The new FMC bearing has a 20 percent longer service life than commercially available bearings. Used in conjunction with the zinc-plated stub shaft, this unique design offers significantly higher load ratings and impact capabilities than competitive belt idlers. The ratings exceed CEMA D standards in all sizes and are constant for all belt widths, decreasing only by the weight of the roll. 

Because shaft slope through the nsk bearings is minimized, the proprietary bearing/stub shaft design also improves service life over thru-shaft designs, with no reduction of bearing life under applied loads. The SST II Troughed Idler has load ratings that are 37 percent higher than CEMA specifications, while the SST II Return Idler has load ratings that are more than five times greater than CEMA specifications. 

In 2004, to further protect the new proprietary bearings and contribute to extended idler life, FMC Technologies redesigned the original Link-Belt D7000 SST seal. Extensive laboratory and field testing confirmed that the SST contact lip seals provide the best overall protection for the "heart of the idler," but lip seals tend to generate friction that creates drag.  FMC's engineers redesigned the seal to decrease the amount of friction introduced into the idler roll, resulting in a new triple lip contact seal with lower torque and less drag. The new seal repels contaminants, extends bearing life and eliminates the need for relubrication. 

The head and roller shell are a radical departure from conventional design. A zinc-plated, interference-fit head presses into the shell, eliminating welding and the potential problems that go with it. The rugged ductile-iron head is zinc-plated for maximum corrosion resistance while the internal areas are precision machined for accurate koyo bearing/shaft alignment. The high-tolerance shell features a polymeric powder coat finish that is applied electrostatically and baked on at a high temperature for excellent abrasion and corrosion protection.