Abstract: A small-sized submersible pump unit having a submersible motor, discharge module, pump housings which are connected by flangeless coupling is disclosed. The flangeless coupling is made using embedded ring segments. The coupled housings each have the covering and the covered parts, and the covered part of one of the housings contains a blind rectangle groove, and the covering part of another housing has a through rectangle groove, and the grooves form a cavity having an embedded ring segment.

Abstract: The invention relates to oil production equipment, more particularly, small-sized submersible pump units that are run in holes on a carrying cable within an additional pipe. The technical result is improvement of reliability of small-sized submersible pump unit in operation, elimination of submersible motor overheating, and simplification of the pump unit mounting. This result is achieved by a small-sized submersible pump unit having a submersible motor, foldable module, pump housings of which are connected by flangeless coupling wherein the flangeless coupling is made using embedded ring segments. The coupled housings each have the covering and the covered parts, and the covered part of one of the housings contains a blind rectangle groove, and the covering part of another housing has a through rectangle groove, and the grooves form a cavity having an embedded ring segment.