A company actively operating and developing electric submersible pump (ESP) systems limits their use for the production of fluids whose free gas volume fraction (GVF) at admission is not more than about 40%. However, the use of a helico-axial pump was proposed, with which such a limit can be exceeded, thus expanding the use of ESPs in oil exploitation.

In order to understand the characteristics and performance of an ESP string equipped with a helico-axial pump, a testing program was established, using oil and gas at the Núcleo Experimental de Atalaia (NEAT) experimental testing site in Aracaju, Brazil.

It was concluded that the use of the helico-axial pump allowed extending the 40% GVF operating limit up to 70% based on the existing test setup, even in the presence of a slug flow regime in the admission. However, it should be strongly noted that at high GVF values, the operation causes significant energy degradation for the pumping system.