26 January 2023

A large UK power station started a project to service and repair 3 cooling water units. Work was required to be completed during three outages, all carried out in 2022.  A fully trained 10 man Corroserve site team, working a 24hr rota, was provided in order to complete the work to the required completion date.

Due to the nature of the Penner System at the plant, and the length of the pipe spool, which spanned over 15m, the project required specialist equipment. This included a crane, slings and lifting equipment. It also required a confined space rescue team, associated access equipment, as being able to ensure safety on site was a key parameter in securing the contract.

 

Pipework

In order to gain safe access, the main cooling water pipeline, the team removed 4 off 54” butterfly valves. Within the contract these valves where then inspected and repaired as required. Over 3 tonnes of silt and other contaminants where then cleared from the pipes.

Ultra high-pressure water cleaning units were  used to remove the existing rubber lining. The rubber lining was found to be in poor condition, The lining showed signs of erosion on the bends and main stream pipework, and undercutting in some of the flange areas.

The pipes were inspected prior to abrasive blasting to prepare the substrate for coating application. The specified coating system of Polyglass VEF and Corrocoat Armagel were applied to protect the substrates from seawater with a high silt content.

 

 

Condenser Cleaning

Manway doors were removed to improve access. The condenser water-boxes were ultra-high pressure cleaned, to remove the existing lining. The condenser tubes where then cleaned using “tube bulleting”. Nylon brushes were used to remove all material from 18000 condenser tubes. The tubes were then dried using foam projectiles. A light test was carried out to identify any blockages.

 

 

After protecting the condenser tubes against damage, the condenser tube face and water box were blasted,  prior to application of Polyglass VEF. This provided full corrosion protection against the seawater.

 

Mechanical Works

104 anodes were removed, inspected and replaced where required. This included the anode holders. The waterbox shell, handles, doors and drains were also inspected and replaced or repaired as required.

 

All work was completed on time, to budget and with no safety issues, another project successfully completed by Corroserve.