Service: Pump replacement

Client: Severn Trent Water

Problem
Severn Trent Water called upon IWS M&E to come up with a solution for a raw water intake pumping station, as it was experiencing multiple pump failures. The pumping station intakes water from the River Severn and the pump design was prone to blocking up due to the wear points on the pumps not reacting well to the dirty water, which included bits of debris from the river.

Solution
The team decided that the original equipment was not meeting their requirements, and it was time to try something different. Working in conjunction with the energy efficiency team at Severn Trent, they changed the design of the pump to remove the usual failure points and build its resilience.

The new design included a modified shaft protection system using a spider bearing configuration to help support the line shaft within the pump and provide a more reliable solution than the original shaft protection bearings.

Challenges
The new design went against the ordinary. The original pump set was heavily modified, and several brand-new components needed to be made for the new design, meaning that the team had to work closely with suppliers to provide an accurate brief.

The site consisted of two different pumping stations located in an upper and lower well and mobile cranes were needed to remove the pump in the lower well. However, the team found that this was limited by wind speeds, so they had to plan the work according to the weather forecast.

The team had to consider the health and safety of themselves and each other while carrying out the work, such as wearing Personal Protective Equipment (PPE) on site, using adequately trained crane operatives, adhering to correct manual handling practices, and keeping a clean and safe working environment.

Result
The project started in November 2022 with seven pumps in total needing replacement. So far, three pumps have been completed, with scope to replace more.

Severn Trent had previously spent money on a filter system for the river water and the new design doesn’t require this function, so the replacement pumps have resulted in cost savings, increased energy efficiency and improved operating efficiency.