Objective: Re-rating Spare Pumps to Meet New Pipeline Process Requirements
Westpower was awarded a re-rate project for a major pipeline client, to re-rate 3 spare pumps based on the customer’s new pipeline process requirements. The entire project took 24 weeks from start to delivery. Westpower’s stringent hydraulic design practices allowed for the pumps to be supplied without factory testing, which drastically reduced the project lead time and cost.
The advantages of a hydraulic re-rate were shorter lead times when compared to purchasing new equipment as well as cost savings due to this solution being a drop-in replacement requiring no modifications to the client’s existing system. It allowed the client to obtain peak hydraulic efficiency, reduce energy consumption and maximize the life of their equipment.
Solution & Results: Hydraulic Re-rating & Customized Pump Redesign
Based on customer supplied site data, it was discovered that two of the three pumps were operating in series at 310 m3/h. The first pump was operating at 297m differential head and 3172 RPM, and the second pump was operating at 274m differential head and 3043 RPM.
Two additional RPM curves were added to match the site VFD readings and are shown in the figure below. The efficiency was within +2% of initial calculations. The sales curve would indicate the head at 3172 RPM and 310 m3/h is 295.5 M (actual head 0.5% high). The sales curve would indicate the head at 3043 RPM and 310 m3/h is 269 M (actual head 1.8% high).
Westpower customized three pumps based on the client’s requirements and this project was delivered on time and on budget. As a result of Westpower’s successful hydraulic engineering re-design, the pumps are currently operating at their optimal design conditions.
