An oil well pipe for a casing, comprising an oil well body, a sliding layer formed on an outside surface of the oil well body and a protective layer formed on an outside surface of the sliding layer, the sliding layer contains an ethylene-vinyl acetate copolymer having 5 to 60 weight % vinyl acetate....http://www.google.de/patents/US5564413?utm_source=gb-gplus-sharePatent US5564413 - Oil well pipe for a casing
