METHOD OF CORROSION PROTECTION OF SUBMERSIBLE PUMP UNIT BY LINING EXTERNAL SURFACE OF ASSEMBLIES THEREOF Russian patent published in 2020 - IPC E21B41/02 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to production of bimetallic protective shells of cylindrical shape, layers of which consist of dissimilar metals and coaxially assembled. Invention is proposed for use in oil industry, in particular, for protection of submersible downhole equipment. Method of protection against corrosion of submersible pump unit by lining external surface of its units consists in arrangement of protected unit of submersible pump unit inside hollow cylindrical protective casing of stainless steel so that points of joint of working units of pump unit, current lead on motor housing and pump base with receiving holes and filter-grid for ingress of formation fluid from well into pump were not closed by lining, and gap between external surface of protected assembly and inner surface of protective casing was uniform and allowed to ensure assembly of structure. End of protective casing is welded along contour to housing of pump unit assembly by argon-arc welding with creation of continuous vacuum-tight weld between it and housing of unit of pump unit and production of single tight welded structure. Welded seams and elements of the pump unit not covered with lining to ensure their serviceability are coated with a metal coating.

EFFECT: technical result is increase in overhaul period and time to failure of submersible pump unit while minimizing energy and labour costs for its uninterrupted functioning.

3 cl, 1 dwg