March 25, 2014. A unique technological process that allows for much greater wear-resistance of pumping and compression string couplings was recently patented by Pervouralsk New Pipe Plant (PNTZ, a member of ChTPZ Group). PNTZ thus became Russia's first pipe manufacturer to introduce the thermodiffusion zinc coating technology for pumping and compression string couplings with the use of zinc powder that has nano-grain surface structure, the company's press service reports.

The idea is to use totally new zinc powder for thermodiffusion coating whose particles are covered with some nano-grain oxide film. The use of this type of powder has made it possible to improve the coating structure and to achieve a considerable enhancement of its properties, primarily wear-resistance.

'The coupling that has been galvanized with the help of this new technology makes it possible to perform over 100 pulling and running operations with pumping and compression strings at oil wells; the coupling also keeps screwing and unscrewing easily even after several years in use,' says ChTPZ Group Production Director Denis Prikhodko.