NEWS

East bursting for Expandit

15 Sep 2008

Our Expandit pipe bursting system is continuing to gain new licensees around the world and the first half of 2008 has seen three new licensees adopt the system, whilst enquiries have come in from several other countries. Expandit installs new, much larger pipes inside old sewers in disrepair.

Trenchless sewer renovation is gaining popularity in developing countries, allowing engineers to tackle problem sewers in urban areas. Where excavation is problematic, or too costly, pipe bursting is being used to install new sewers. Even in a size-for-size renewal,

Expandit succeeds where pipe lining would fail because of excessive structural deterioration of the existing pipe. Expandit is a hydraulic bursting mole that is designed to work from existing manholes or small excavations. It replaces damaged pipe with minimal environmental impact and disruption. Its hydraulic bursting action breaks up the pipe and forces the fragments into the surrounding earth, dealing with a range of pipe materials, including clayware, pitch fibre, concrete, asbestos cement, cast iron and uPVC.

The mole is kept on course by a chain winch, while a hydraulic ram pushes the device forward. Short pipe lengths, whether in clay, concrete, or polyethylene, are lowered into the manhole and jointed as they follow the bursting head along the course of the original sewer pipe. Typically lengths of up to 100m of pipe are installed in this way, although 300m sections have been achieved in favourable conditions.

The fact that the system works by hydraulics is significant. Conventionally, pipe bursting moles are operated by pneumatic pulses that produce vibration, noise and ground heave. In contrast, hydraulic operation is non aggressive. It is ideal in congested areas where other buried services could be damaged by pneumatic bursting.

Romania - In March our new Romanian licensee, MNS Cleaning Services took delivery of their new Expandit pipe bursting system. Our Expandit team flew out to the port city of Constanta to train MNS and assist with their first project. MNS’s roots are in sewer cleaning and jetting but with many of the city’s old, vitrified clay sewers needing rehabilitation, they expanded into CIPP lining in 2007. They wanted the Expandit system for sewers which are in too bad a condition to reline. The Expandit system fits well alongside MNS’s CIPP system, allowing them to offer a completely trenchless rehabilitation solution. Since March, MNS has successfully completed three more Expandit projects.

Egypt - Shortly after their return from Romania, the Expandit team flew out to Egypt; where our new Egyptian licensee Robou Construction, a directional drilling specialist which has diversified into sewer renovation, was due to start its first Expandit project. A number of critical sewers in Cairo’s heavily congested city centre are due to be replaced. Many of the city’s sewers are in excess of 8 metres deep. The vitrified clay pipes, which range from 8” to 24” ID, are in poor condition with partial collapses and deformations in many places. Robou chose Expandit because of its efficient operation and its ability to be used in areas of restricted access. The first project was to replace a 1 km section of 8” diameter pipe in Cairo city centre.

In the past few years Expandit technology has been licensed in Japan and Korea, as both countries have embarked on renewal programmes for ageing concrete sewers.