Pipework : Double Wall Piping : New !!. EVOH bonding technology" ..... New technology ... for double-wall underground oil pipes ... eliminates the problem of pipe walls separating ... The new technology of bonding double-walled pipes makes Pipework pipes, when compared to the old double-walled pipes that use Polyarylamide inner material (one of the materials that are most resistant to oil solubility) stacked with HDPE (high density polyethylene), which causes pipe peeling ... Pipework pipes have adapted the latest technology to bond the walls of the two different materials. Therefore, the pipe walls cannot be separated anymore, completely eliminating the problem of pipe peeling ...... Pipework oil pipes have no underground connections, eliminating the problem of leaks and seepage, creating confidence and quality that is worth the price, saving costs in the long run.