Posted: 26 September 2013
Comments (1)

Innovation is key

It’s saving time, money and minimising disruption for the public – Ian Hopper talks about National Grid’s pioneering keyhole technology for street works.

Share Share on Facebook19Share on LinkedIn0Tweet about this on TwitterShare on Google+0Email this to someone

Innovation is key

Innovation is key

"This sort of innovation is important because the money we save in road closures should help minimise costs to energy consumers."

Ian Hopper, National Grid’s Technical Officer


Since being introduced to British roads in 2009, keyhole technology has shaved hundreds of days off repair times.


Many of us have sat in traffic jams complaining about lane closures caused by roadworks. Now there’s some relief on the way thanks to National Grid’s investment in pioneering ‘keyhole for roads’ technology for street works. Technical Officer Ian Hopper explains how it’s saving time and money, and minimising disruption for the public.


Every year we have to repair hundreds of leaking joints on gas mains under the road. Traditionally this sort of job means closing a lane and manually digging a hole using jack-hammers and shovels. Teams then climb inside the hole and make the repair, before contractors move in to reinstate it. It’s a process that can typically take up to five days.

But for the past six years, we’ve been researching and developing keyhole technology that will carry out this type of repair.

Put simply, we cut a 600mm diameter core hole out of the road and then vacuum the material underneath until we expose the gas main. Repairs are made using long-handled tools and we backfill the hole with the material we sucked out. The core is then fitted back into place and we can open the lane to traffic. The whole process takes about four or five hours.

In September, we unveiled our second-generation fleet of machines to carry out this work. Previously we used two lorries – one to cut the core, and the other to vacuum the spoil. Now our ‘combined’ vehicles are fitted with machinery that can do both of these operations in one.

We’re introducing six new units, four of which will be deployed in London and the South, while two will be used in the North West. Once they’ve proved themselves, we’ll transfer our first generation fleet of six vehicles out of London and into our networks in the Midlands and the North East.

I’ve been involved in the development of the new vehicles so I feel very proud and excited to see them driving into action. They’re more efficient, more powerful and better for the user. The suction hose, for example, is remote-controlled, so operators won’t need to manually pull the equipment into place.

They’re monitored by computer, so we can record and analyse items such as their running time, the amount of fuel they use and how much spoil they move. In certain cases, we can even fix faults and reset parameters remotely, even from a smart phone.

And the units can do much more than fix leaking joints. When fitted with other specific items of tooling, a two-person team has the capability to carry out other duties, such as water extraction, mains connections and repairs.

Because they’re quick and easy to use, these machines can also be deployed out-of-hours in certain situations, so we can start a job at 8pm and be finished by 4am. In cases like this, we normally communicate with residents via letter and use acoustic screening to reduce the noise.

This sort of innovation and flexibility is important because it can cost up to £2,500 per day to close a lane of a road, depending on who owns it. If we can reduce the time work takes, we should also reduce costs, which may ultimately save money for energy consumers.

National Grid is committed to developing better ways of doing the essential work for which we are responsible. We hope customers and communities see this new innovation as a small part of the company’s desire to continuously improve its operations.

Driving forward with the next stage of our keyhole technology will also give us a positive public image. We’re saving costs, we’re demonstrating innovation and efficiencies and we’re being more productive, which is what RIIO is all about.

I’ve worked at National Grid for 36 years and I believe we’re the only utility company in the UK using this combined technology on one vehicle. With a bit of adaption, I strongly believe that it can be used by other utilities. Water companies in particular have already started to show an interest.

So the technology is out there and it’s getting a lot of focus in the trade press. Going forward as we develop it still further, I think it will become a standard way of working, not just in the UK, but across Europe as well.

To find out more

Click here for more information about keyhole technology.

Gas innovation in full flow