Locals like to say that everything is bigger in Texas and this is certainly true of the world’s largest pneumatic pipe ramming hammer. Unveiled by manufacturer HammerHead Trenchless Equipment at the Underground Construction Technologies expo in Houston, the 34 inch (860mm) device can install pipe casing up to 180 inches (4500mm). This is hot news for Underground Utilities magazine which sent me to visit the exhibition and find out what is new in the world of underground construction.
For those of you (like me) who are not expert in pneumatic hammers the technology is mainly used to ram steel casing through ground in locations where opening up a trench is not an option such as a road, a railway or a river. The significance of the new piece of equipment is that it can be used to install a much larger diameter pipe casing underground than HammerHead’s earlier 24inch (61mm) hammer. It can also push the casing over longer distances through the ground and enable quicker installation than smaller heads.
HammerHead CEO Brian Metcalf tells me that the hammer was created in response to clients that had requested the company provide larger solutions. After a recent field test in Ontario where it successfully placed a 185ft (62m) of 72inch (183mm) steel casing the product has now been released for production.
Beyond pipe ramming the event has also highlighted some other important issues in the underground construction sector,. Contractors working in the field of Horizontal Directional Drilling (HDD) revealed that clients are increasingly asking for real time monitoring of the HDD drill head as it bores its underground trajectory. They also highlighted the challenges of undertaking a bore without ground investigation, which is more common than I had realized. Coming from an engineering background I expected that any significant HDD bore would be carried out in ground that had been investigated to properly engineer the drive. However a lot of projects do not undertake this step and do not take core samples, instead they rely on the considerable expertise of the contractors who in many, many cases successfully deliver a new pipeline thanks to their experience with local conditions. Unfortunately there are also many projects where the ground turns out to be different to what was expected or contain obstructions that were not expected and contractors fail to place the new pipeline as planned. “One or two $5000 bore holes could save the client $200,000 in construction cost,” said one participant.
One of the biggest challenges of this event has been working out what to attend. There were 11 educational sessions running simultaneously on subjects from cured in place pipe to HDD, pipe bursting and regulatory updates. Day 2 is no different and I will be finding out more about microtunnelling, manhole repair, drilling in hard rock and keyhole technologies.