MSc. Sergio Caicedo
Artificial Lift Expert at UPC Global
There are many Electro Submersible Pumping (ESP) wells continuously growing with a significant percentage of global oil production, however, it is amazing the large number of misconceptions that still exist related with this equipment.
Based on a misconception there is the possibility of having an over-expectation and therefore the decision is made to use an ESP in a well and then face with the operational reality whose conditions make it impossible to achieve the production target and/or to achieve an acceptable run life. The opposite may also happen, that the prediction is very pessimistic therefore the ESP is not installed, but then studying experiences of other colleagues from other companies we learn of successful field tests under the same conditions. It is for this reason it is very important to understand how these equipment work because the decision to employ or discard them are based on misconceptions or misunderstood communications between management and engineers.
Among the misconceptions commonly related with ESP are the following
- ESP delivers pressure in a manner analogous to Sucker Rod Pump and PCP.
- Critical variables for each equipment component are understood.
- The pump will produce its capacity at the operating frequency.
- A high gas-to-oil ratio GOR rules out the use of ESP.
- With the available field experiences, it is possible to make conclusions and definitive decisions.
- The decision is economically justified.
- The ESPs are always associated with high electricity consumption (HP KVA)
- The most influential variables in the production process with ESP are clearly identified.
- High viscosity corrections are simple.
- Surveillance consists of acquiring and monitoring the variables.
- Operational practices of other methods are applicable.
In this article we will discuss each of these to show both at the managerial and engineering level the need to fully understand the operating principles of each of the components of the ESP in order not to have erroneous expectations either because they are overly optimistic or pessimistic.