COUPLING DEVICE WITH COATING FOR OPERATION IN GAS AND OIL WELLS Russian patent published in 2016 - IPC E21B17/10 

FIELD: machine building.

SUBSTANCE: invention relates to the coupling device with coating for operation in gas and oil wells. The coupling device with coating is suggested for operation in the gas and oil wells is suggested, it contains one or more cylindrical bodies, one or more couplings located near the outside diameter or internal diameter of one or more cylindrical bodies, coating out of hard alloy on at least part of opened outside surface, opened internal surface or thereof combination of one or more couplings, and coating on at least part of the internal surface of coupling, outside surface of coupling or combination of said surfaces of one or more couplings. Wherein the said coating contains one or more layers with ultra low friction coefficient. Wherein one or more layers with ultra low friction coefficient are selected from: amorphous alloy applied by method of chemical reduction of Ni-Ph composite, graphite, MoS₂, WS₂, composite based on fullerene, metal-ceramic alloy based on boride, quasi-crystalline material, diamond based material, diamond-like carbon, boron nitride, carbon nanotubes, graphen sheets, parts of metal with high ratio of vertical and horizontal dimensions (i.e. length to thickness ratio), materials of annular shape, comprising carbon nanorings, longitudinal particles, and their combinations. Besides, the couple device contains one or more intermediate layers located between the coating out of hard alloy and coating with ultra low friction coefficient. Also the method is suggested of said couple device use in gas and oil wells.

EFFECT: increased wear resistance of the coupling connection, and reduced corrosion, erosion and other deposits under well conditions.

35 cl, 68 dwg, 1 tbl