High Viscosity Test Of A Crude Oil Pump

Abstract

In 2014 a full scale high viscosity pump performance test was performed for a 2-stage vertically suspended (VS1) API610 pump. The high viscosity test scope was part of an ongoing EPC project and exclusively conducted for industrial purposes. The objective was to simulate real field operation with crude oil and qualify the pump for the given field conditions and requirements. Furthermore, the reason for conducting this test scope was the uncertainties in published methods of predicting high viscosity fluid pump characteristics, limited available literature, hence reduce field operation risks. The official test scope was divided into two main scenarios: 1) Start-up test at minimum. flow and a viscosity of 3075 cP, 2) Pump performance test with an intermittent duty point (reduced flow) of 850 m3/h-125 m (3654 USgpm- 410 ft), and a viscosity of 1075 cP. Internal tests with various viscosities from 480 cP to 3075 cP were also done in preparation for the official tests. Measured results were then compared to published methods for pump characteristics viscosity correction. The objective for these additional analyzes was to evaluate possible alternative approaches in order to improve uncertainties with viscous prediction and ultimately reduce the number of tests/test scope in future projects. It should be emphasized that this comparison is simply for discussion within the industry and not for validation of published methods of viscosity correction for pump characteristics. The test results provide valuable insight on the effects of high viscosity on centrifugal pump performance curves, allowing a more accurate rating and possibly a better optimization of the process equipment, e.g. electrical motor, valves, cooling system, by improving the flow characteristics predictions.