Environment Agency extends condition monitoring

London - The Environment Agency is increasing its focus on condition monitoring (CM), as evidenced by its installation of an online system at a remote pumping station in Winestead, near Hull. The unit operates two 240kW vertical spindle, axial flow pumps that can each transfer 3,700 litres of floodwater per second back into the river.

Recent flash flooding incidents have highlighted challenges faced in maintaining pumping units that are not in continuous operation, explains Simon Thompson, operations engineer based at the EA's Hull office.

When Thompson joined the EA from British Sugar 18 months ago, there was only limited information on the condition of all the pumping stations under his remit. Some of the sites had been owned previously by other authorities and subsequently handed over to the agency, with little or no maintenance history.

"One of the major challenges for me was how to decide which pumps should be refurbished with little or no previous maintenance history to go on," said Thompson. "Very often we would be faced with a breakdown before one of our field engineers would be required to refurbish the unit."

Thompson was familiar with the application of vibration monitoring at British Sugar, where patrol monitoring was used to assess the condition of critical plant. However, due to the remote location of the Winestead facility, he opted for an online system - a FAG DTECT X1 system from Schaeffler.

According to Thompson, the monitoring system "has given me the confidence that the two pumps are doing what they should be doing. Without the system we could have one pump that is an hour away from a catastrophic failure, but we wouldn't know that."

However, a spokesman for the Environment Agency insisted that the body is proactive in monitoring the condition of its flood water pumping equipment and has been using the technology for several years. The use of CM, he said, is now core to our maintenance and design assessments and its use will be considered in every relevant project. 

"We recognise that techniques such as reliability centred maintenance (RCM) and techniques of condition monitoring achieve a high level of plant availability at least whole life cost through a risk based strategy," he said. " We assess all our assets for their impact should they fail and from this information form management and maintenance programmes to keep them fit for purpose within budget constraints."

According to the spokesman, the Hull Winestead pumping station (PS) reflects the wide-scale use of CM by the Environment Agency. The focus, he added, is to ensure that the benefits which accrue from the investment in the technology are positive and value for money is secured. 

Likewise, the Agency representative cited an application at the Lake 4 Pumping station in the Thames region where CM was installed in early 2006 on two large Archimedean screw pumps at the time of their removal for scheduled maintenance.

"Thermal imaging, oil analysis, power and vibration monitoring are all techniques available to our engineers. We use portable monitoring equipment on many of our smaller sites and we do consider the installation of permanent monitoring usually during initial design or refurbishment," the spokesman continued.

Environment Agency engineers do encounter certain limitations in the use of CM. Its pumps for example often operate on full load only during extreme rainfall events and even short periods of stable operation are rare, so obtaining a trend of condition indicators can be difficult.