Innovation Exchange challenge: Safely making probe holes for subterranean gas inspection

When determining the presence and existent of gas from leaks, it is necessary to form a series of small holes through hard surfacing materials to then insert a small gas detection probe. Currently this hole is formed by a hardened steel tool driven by a manually lifted drop-weight, the tool is termed a Bar-Holing tool or Searcher bar.

Bar-Holing is one of the first steps in verifying and identifying possible gas leaks from underground pipes. The tool is operated by a single worker and is carried in their service van. Typically, between 15 and 30 holes are required to verify the presence of a leak and to pinpoint the likely source. The holes are 15mm diameter to allow insertion of a 10mm gas detection probe and are 200mm deep in the footway and 380mm deep in the carriageway.

The holes can be required in a variety of common construction materials from reinforced concrete, dense bitumen macadam (road construction), sub-base and compacted soils and stone. It is observed that the time to create a hole varies from a minute or less in softer materials to as much as 10 minutes or more in concrete. In instances where 20+ holes are required, this can represent a significant time cost.

There is an ergonomic hazard when using the current tool due to the tool weight of 10kg, its natural imbalance during use and position relative to differing physiques. Repeated use can also be uncomfortable for the operator due to the percussion.

Cadent are keen to explore alternative tools or devices which can significantly reduce employee health and safety risk without a loss of efficiency and without substantially increasing the weight/bulk to be transported.

Because of the risk of striking underground cables the tool is 22kV isolated, the tool is also considered intrinsically safe with low risk of sparking, which could cause an explosion risk. Solutions must be similarly intrinsically safe; when considered in the past, this has precluded the use of electrical power tools due to the heightened likelihood of sparking at the cutting bit.

We require a device that can create 15mm diameter holes to 200mm and 380mm controlled depth in various substrates (reinforced concrete being the hardest) that does not create a spark hazard, is intrinsically safe to 22kV, is comfortably usable by all able-bodied operatives, mitigates vibration shocks and is as readily transported as the current tool.

For full functional and technical requirements and operating conditions, please visit the Innovation Exchange site at the link below.

Entrants to this competition must be established businesses, academic institutions, start-ups, SMEs, or individual entrepreneurs, who are UK based or have the intention to set up a UK base.