THE SITUATION
A customer operating two critical Grundfos pumps on a chiller system faced rising energy costs and increasing concerns around asset reliability. Both pumps operated continuously on a duty/duty cycle, with no standby unit available, making them essential to maintaining production.
Having not been serviced for several years, the pumps were showing signs of age and reduced efficiency. To minimise operational risk while improving performance, the customer scheduled the refurbishment of one pump during the Christmas shutdown period.
THE SOLUTION
The pump was removed by the customer, collected by HAYLEY 247 DEXIS, and transported to our Dudley repair facility for a complete overhaul.
Following a full strip-down inspection, our engineers produced a detailed ‘as found’ condition report before carrying out the refurbishment. Key work included:
– Grit blasting the pump volute casing and stuffing box to prepare the internal surfaces.
– Applying Belzona 1341 Super Metal Glide coating throughout the pump’s internal water passageways to improve hydraulic efficiency.
– Testing the drive motor and replacing bearings, seals, gaskets and the mechanical seal.
– Checking and recording all internal clearances against both WIMES and OEM specifications.
– Repairing cavitation erosion found on the impeller inlet vanes using Belzona 1111, before applying Belzona 1341 and dynamically balancing the impeller.
– Completing a full performance test to BS EN ISO 9906, with results benchmarked against the original OEM performance curve.
Based on the operating conditions and energy tariff, the refurbishment was expected to deliver an 8% improvement in hydraulic efficiency, reducing annual energy costs from £42,136 to approximately £38,765.
THE RESULT
Performance testing confirmed a 1.4 kW reduction in absorbed motor power, demonstrating a significant improvement in pump efficiency.
The refurbishment is now delivering an annual energy saving of £3,188, while also restoring the pump to a reliable operating condition and extending the service life of a critical production asset. The project has provided the customer with lower running costs, improved reliability and greater confidence in the long-term performance of their pumping system.