Have you looked at the operation in the Alberta Oil Sands?
They use a special casted polymer for their lagging.
THe Rheinbraun coal field operations use an extruded polymer that looks similar to the Oll Sands. This polymer is applied to a rotating pulley when to lagging is applied from a fixed end tube fitting.
I can put you in contact with Syncrude's operating engineers to allow your further investigation if you have not already done so.
Conveyor Dynamics, Inc.
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