WORKING MEMBER OF A BORE HOLE MULTISTAGE PUMP (VARIANTS)

摘要

The invention relates to multistage pumps for extracting oil from wells. The inventive working member of a downhole multistage pump comprises a working wheel (4) and a guiding unit (5). Said working wheel (4) and a guiding unit (5), each or both, are made either of an aluminium alloy, or steel or iron and are provided with a ceramic Al₂O₃ coating which is applied to the steel or iron surface and consists of at least two layers. A highly adhesive polymer coating is applied to the ceramic coating. Said invention makes it possible to increase the corrosion stability of the working members, the wearability thereof, to reduce salting deposits, asphaltene-paraffine precipitations, the weight and vibrations.