Methodology for Analyzing the Actual Technical Condition of Downhole Pumping Equipment

Abstract

The reducing in the pressure characteristic of the submersible pump during operation occurs as a result of the combined action of a number of reasons. Pumping equipment wears out due to waterjet destruction of flow channels. The characteristics of submersible pumps are captured at the factory on special stands. At large group groundwater intakes, wells are equipped with an automated control system that allows testing the pump at the workplace and promptly making a decision on its replacement if the pressure characteristic is unacceptably reduced. The actual pressure characteristic of the pump H н = f (Q) can be plotted directly in the well with a sufficient degree of accuracy. To determine the degree of wear of the pump, its pressure characteristics are compared before installation and at the time of taking readings. The article describes a well strapping scheme for measuring the specific flow rate and pressure characteristics of a submersible pump. The purpose of the study is to derive a dependency for constructing the flow-pressure characteristics of a submersible pump at its workplace and to develop a method for accounting for its wear during operation, which allows predicting a decrease in well productivity over time. An expression is proposed to describe the characteristics of the pump at any time, calculated from its installation in the well. The analysis of the reducing in the pressure characteristics of pumps produced by various manufacturers in the wells of the existing water intake of underground water is presented. It is confirmed that the intensity of the pressure reduction depends on the duration of the pump operation in a given well, the material of the pump impellers and the sand content in the pumped water.

Keywords

• submersible pump
• pressure reduction
• downhole pump wear
• pump test at the workplace
• pressure gauge