Gardner Denver UK Achieve Environmental Impact Award

Gardner Denver UK Ltd. and Brit-Tip combined with OSDS Ltd. to achieve: Winner of the Environmental Impact Award for the development & manufacture of the 7,5Ton GVW Combined Core & Vac. machine.

Repairs to underground Gas and Water Pipes are difficult to access and complete, in a timely cost effective manner. Using traditional methods, can involve sending three vehicles to the same job. The first vehicle will carry the barriers to cordon off the repair area. The second vehicle will dig out the surrounding ground area and make the repair. The final vehicle, will then in-fill the hole and repair the Tarmac surface. A typical repair can take over a week, whilst these individual units wait for each other to finish their work. In addition to the above costs, local Councils will charge the Contractor up to £15k per lane per day, for closing or reducing the width of the road.

With this in mind, Steve Dunmoore of OSDS Ltd, had an initial idea to combine all these functions onto one truck and keep the weight of the truck under 7.5ton GVW, so that it can be driven by someone with a normal car licence. Steve approached Gardner Denver UK and Brit-Tip bodybuilders, to help in developing this new concept vehicle.

With the Core & Vac vehicle, specialist equipment detects the underground leak. This can be through ‘sniffing’ the ground or passing a camera/microphone along the pipe, which looks and listens for leaks. Once detected, the operator knows exactly how far the camera has travelled, which is then marked on the surface of the road. Using a rear mounted camera, the driver can reverse the vehicle into exactly the right position, over the leak. 

A patented stabilising device steadies the vehicle, whilst a 100mm diameter cutter, drills an initial hole through the top road surfaces. When extracted, this small core shows the exact depth of the top surfaces. This is then marked on the side of a 600mm cutter and a larger hole is then cut. Once through the top surfaces, a sleeve is inserted into the 100mm hole and the entire 600mm core extracted.

Gardner Denver compressors are used to power ‘air picks’ and drills, to remove the sub-surface, which at the same time is Vacuumed into a tank on the back of the vehicle. Most leaks are on pipe joints and special ‘long handle’ tools are used to carry out the repair. This eliminates the operator from entering the hole, which is a very dangerous task. With traditional methods, a further team would be needed to shore-up the sides of the hole, to make it a safe place to work.

Once the pipe has been repaired, the original sub-surface is put back into the hole and compacted to the original compaction rates. This avoids a future pot-hole, or ‘hump’ in the road. Using a special fast setting grout, the original core is then placed back in the hole, to finish the repair. The road can be re-opened in less than 1 hour from this stage. With Core & Vac, it is not unusual for one team to carry out 3 repairs in a day.

Additional features on the vehicle, are a water jetter, hydraulic power for drills, etc and hand wash facilities. We have even ducted the air from the GD Hydrapk into a small drying compartment, to take care of operators ‘wet gear’.

Gardner Denver UK Ltd are the main contractor in the build of the vehicle and each unit is supported by a Gardner Denver – Repair and Maintenance Contract. Core & Vac has only been in production for 2 years, but Scotia Gas Networks have already seen the benefits of this machine and have seven units on the road. Other Utility companies such as Northern Gas Networks and Wales and West Utilities are now very close to ordering the Core & Vac.

When you take into account lost time through traffic congestion, pollution caused by stationary traffic, faster repairs, health and safety of workers and the elimination of at least 2 vehicles per repair, it is easy to see how we won the ‘Environmental Impact Award’ at the UK Eneregy Innovation awards ceremony.