Fewston Reservoir | 140-Year-Old Valve Repair and Refurbishment
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Blackhall

140-Year-Old Valve Refurbished and Re-manufactured

What's the story?

Fewston Reservoir, originally built in the period between 1876 and 1879 is located in Washburn valley to the west of Harrogate in Yorkshire, England. The capacity of the reservoir is 3.5 million cubic metres and is adjoined with the 3.9 million cubic metre capacity Swinsty reservoir. In 2011 during a statuary inspection, concerns were raised by the reservoir's panel engineer on the leaking valves that controlled the outflow from Fewston to Swinsty. Over recent years the valve had started to leak, and was progressively getting worse. The original valves had 9" square teak shafts, were over 54ft long and sandwiched between two 1.5" thick wrought iron plates. These along with the cast iron valve gates were calculated to weigh just over 9 tonnes each. The Blackhall valvologists were called in to inspect and diagnose the problem and conduct feasibility studies to provide the best possible refurbishment options.

Valve Inspection, Condition and Survey Report

An internal inspection survey was carried out by our confined-space-trained personnel to determine the condition of the valves. The inspection reports detailed the cause of the excessive leakage and concluded that critical failure of the valves was imminent should they be left unrepaired. On receiving the reports, Yorkshire Water proceeded to entrust Blackhall Engineering Ltd in carrying out the full removal, overhaul and refurbishment of these 140-year-old valves. The refurbishment plan, which combined both repair and replace elements, was a financially and environmentally conscious one, and in-keeping with the importance of heritage to Blackhall.

Valve Removal and Lifting Services

One of the main challenges in the valve refurbishment programme was actually crafting lifting equipment capable of accessing such a narrow space in order to remove the 9 tonne valves from the 59ft (18 m) deep enclosure at the base of the valve tower. The safe removal of the valves took 3 days from start to finish.

Valve Strip and Inspection Report

The valves were then delivered to our Brighouse facility to be stripped and inspected. A detailed report was presented to the customer and refurbishment commenced. This is where the process of bringing the valves back to life began.
 

"We would like to thank Blackhall for their engineering and on-site services on the Fewston Project. Another competent and Great Job by the Blackhall Team!"

Craig Burgon
Project Engineer-Asset Integrity
Yorkshire Water

Valve Refurbishment and Remanufacturing

Reverse engineering was carried out on the valves via detailed examination of their construction and material composition. Their overall condition was reasonably sound, however, redesign using the latest advancements in technology meant the valve's overall robustness and longevity could be enhanced. Design modifications included changing the valve stem material to stainless steel and increasing the diameter of the shaft to improve strength, while stress calculations indicated how the valves would work under pressure.

Patterns were developed using 3D Solidworks in order to remanufacture castings in the UK's leading ISO approved Foundry. The seat door was also refurbished and re-lapped, while the door frame seat ring was remanufactured and re-lapped to match the existing door. A laser alignment test was performed to check the straightness of the shaft. The valves were shot-blasted and finished with a WRAS-approved paint prior to final assembly.

Back to site

The newly upgraded valves were returned to Fewston Reservoir and safely reinstalled into the 59ft (18m) deep enclosure. Today, both valves are running soundly with no leakage detected, and should be fit for another 150 years.”