Lanes Group has used a newly developed lining system for the first time to seal four large-diameter pipes that are vital for keeping a seaport operational.
The pipes feed water from a pump house to refill the dock basin behind sea locks at Shoreham Port, West Sussex. If they had not been rehabilitated, they were at risk of failing.
Lanes Group, the UK’s largest drainage and water utility company, worked in partnership with lining supplies specialist RSM Lining Supplies and UK seal and gasket manufacturer VIP-Polymers to complete the innovative project.
Space limitations in the pump house and on the dockside, sharp bends in all four pipes, plus the need to keep the port continuously operational, meant the new system was the only practical pipelining solution.
A series of inter-connecting rubber seals combined with short cured-in-place-pipe (CIPP) liners, called patch liners, were used to fully line all four cast-iron pipes with lengths from 20 metres to 42 metres.
Brian Rousell, Director of Engineering at Shoreham Port, said: “Lanes Group really took the effort to understand the criticality and working conditions for this project. It then delivered on-specification, on-time, and on-budget to keep the port’s infrastructure working well into the future.”
Gary Carey, Technical Manager of Lanes Group Reline, the company’s lining division, said: “Shoreham Port came to Lanes Group because it needed a long-term, cost-effective maintenance solution to futureproof the pump system, which is critical to its operational and commercial success.
“We’ve shown we can provide asset owners with a new option that overcomes significant challenges when rehabilitating hard-to-reach pipes, where replacing them would be enormously disruptive and costly.
“It’s also a very good example of partnership working between three expert service providers. Our solution has a design life of over half a century, helping to safeguard the port’s future.”
VIP-Polymers Sales Director Jim Shaw said: “The project was perfect proof that our new system works, so gave us a real sense of achievement. The product was tested in one of the most difficult environments it will ever be installed in.”
RSM Lining Supplies is an international supplier of equipment and materials for trenchless rehabilitation and has worked as a trusted partner with Lanes Group on numerous projects for nearly 20 years.
The company’s Technical Business Development Manager, Richard Wortley, recommended bringing VIP-Polymers into the project. He said: “This was a major undertaking, completed under exacting time pressure.
“More than 500 seals were installed, and a total of 126 metres of pipe were lined. It succeeded because the right technology was combined with Lanes Group’s operational excellence and determination.”
The four pipes take seawater from the dockside pump station and feed it into a 500m-long underground channel that outfalls in the dock basin to replenish water lost when the sea locks are open.
The pipes, each with a flow rate of up to 8,500 tonnes of seawater per hour, had been found to be leaking. This was increasing the cost of water pumping and putting the long-term integrity of the system at risk.
Gary Carey and Richard Wortley agreed, during a site inspection, that conventional hot water or ultraviolet light cured in place pipe (CIPP) lining were not viable solutions.
However, VIP-Polymers, a global leader in design and manufacture of pipe sealing systems, had just developed a new lining system called VIP-WECO CONNECT that turned out to be an ideal solution.
The product, based on the company’s long-established VIP-WECO seal system, allows interlocking rubber seals, held in place by stainless steel rings, to be connected together to create a hybrid liner system of any desired length.
The system was combined with the installation of patch liners at four 20-degree bends in each pipe.
Lanes Group completed the lining programme in just six weeks, meeting a firm deadline set by the port, and overcoming an unforeseen technical challenge along the way.
Shoreham Port’s engineering team installed scaffold platforms in a 10-metre-deep pump chamber to give the lining team access to pump lines, which run two metres below ground.
The 1335mm-diameter pipes were first cleaned using high-pressure water jetting to remove deposits of rust and scale. This created the smooth surface needed for the lining system to form a watertight seal.
Lanes Group then implemented a smart system of work to ensure its four-person team stayed safe and worked as productively as possible, while being monitored at all times by a three-person confined space rescue team.
Two of the four pipes had to be operational at all times. This left the other two free for the lining operatives to work on, but only when not flooded by an incoming tide twice each day.
To overcome this problem, divers brought in by the port sealed the pump shaft serving one of the lines with a steel plate, supported by a back-up pump system to remove seeping water. This allowed the lining team to work continuously on one pipe.
The second pipe had to remain unsealed in case it was needed at short notice to replace one of the operational pipes. Because of this, it could only be worked on when tide levels allowed.
Lanes Group consulted tide charts to plan shifts so operatives could safely maximise time spent in the unsealed pipe. When the tide rose to a specific height, they moved into the sealed pump line to work alongside their colleagues.
A second challenge was the discovery, once the pump lines had been cleaned, that each one narrowed by 125mm over a 10-metre length as they left the pump house.
The solution was for VIP-Polymers to manufacture a series of nine bespoke rubber seals, each one stepping down in diameter, based on measurements supplied by the Lanes Group lining team.
Four sets of the seals, one for each pump line, were delivered to Shoreham Port as they were needed. When combined with a flexible patch liner, the diameter change could be accommodated.
Lanes Group’s team was also helped by another innovation introduced by VIP-Polymers – a locating lip incorporated into each seal.
By simply running a finger along the locating lip, Lanes Group’s operatives could feel that the seals were connected properly, not just see they were.
Jim Shaw explained: “The VIP-WECO CONNECT system is installed in pipelines which, by their nature, are dark and confined spaces even though 110v portable light sets are used, as was the case here.
“Given the restrictions caused by tidal flows, speed of install was one of the major design considerations for this project, and this innovation enabled a 50% increase in installation speed.”
It was an aid they were shown when they visited the manufacturer’s factory in Huntingdon, Cambridgeshire, to train how to fit the seals in a mocked-up pipe.
Jim Shaw said: “The raised sealing lip gave the Lanes operatives the edge, literally. They did a brilliant job of choreographing a way to fit the seals in very difficult conditions.
“Their determination to get the job done was hugely impressive, and a big part of the project’s successful outcome.”
Shoreham Port handles around two million tonnes of cargo and manages 14,000 leisure boat movements a year. It has EcoPort status due to its commitment to decarbonisation, which includes use of wind and solar power generation.
The 110-acre site is also home to an industrial cluster with 175 small and medium-sized businesses, many related to the port’s activities. It is also the location for the 420MW Southwick gas-fired power station.