Patent ID: 8701714

Claim:
Abrasion resistant polymer pipe, comprising a first, abrasion resistant inner layer ( 1 ) and a second, structural layer ( 2 ), which is placed on the outer side of the inner layer, said first and said second layers comprising extrudable polymer materials, wherein there is an intermediate layer ( 3 ) between the inner layer ( 1 ) and the structural layer ( 2 ), abutting with the inner layer and said intermediate layer functioning as an indicator of the wear or depletion of the inner layer, and the intermediate layer ( 3 ) is electrically conductive having a resistance in the conductive range, and wherein the weight ratio of the abrasion resistant material to the structural material is in the range from about 1:100 to 50:100, the thickness of the inner layer is in the range from about 0.5 to 40 mm, and the total wall thickness of the pipe is in the range from about 20 to 100 mm.