The Low Shear centrifugal pump is a product from years of development work through several Joint-Industry-Projects, financed by oil companies and the Norwegian Research Council. Particularly, work has focused on comparative studies with commercial pumps. Figure 2
presents an example of a comparison test between a Low Shear pump and a commercial single-stage pump. This test reflects typical results achieved with an API 44 crude (highly shear sensitive) at concentrations of 200 and 600 ppm. Generally, the shear-performance of the Low Shear pump is a design factor. Hence, a well-designed pump will simultaneously match both the hydraulic duty point and the required droplet performance. The Typhonix Low Shear Pumps are BB4 style, built according to API 610. The photo of Figure 2 shows a Low Shear API 610 pump during a factory test at Typhonix.
Figure 2. Left: Example of typical test results of the pump development project. Right: API 610 Low Shear Pump during factory test at Typhonix. (Click to enlarge figure)
Field installation and experience
In 2017, two Low Shear pumps were installed on a platform offshore Malaysia. The pumps deliver produced water to a filter system and was acquired to improve separation performance. The platform reports (October 2019) that the pumps are still running fine after more than two years in continuous operation. Figure 3
shows, at the left, the results of a Droplet Performance Test done at Typhonix in 2017, upon delivery. The pumps were designed to not give any droplet break-up of oil droplets of 15 µm or below. The right diagram is the result of an offshore verification test executed by the end-user some months later. Operating conditions OiW concentration 200 to 1000 ppm, API 42 crude, high concentration of corrosion inhibitor.
Figure 3. Left: Results of Droplet Performance Test at Typhonix upon pump delivery. Right: Results of offshore verification test executed by end-user on site. (Click to enlarge figure)