InfrastructureDetecting buried plastic pipes

Published 8 July 2010

As the utility infrastructure ages, metal pipes, such as cast iron gas mains, are rapidly being replaced with plastic ones; buried plastic pipes are notoriously difficult to detect using current methods which are expensive, inefficient, and in many cases do not produce the quick and accurate results required; an Oxford University spin-out offers a solution

Difficult to find underground, despite its size // Source: kwhpipe.ca

Sensor and tagging technology that can accurately detect plastic pipes buried deep beneath the ground has been developed by Oxford University spin-out, Oxford Electromagnetic Solutions (OXEMS).

The technology is a response to the growing levels of plastic being used in the utility infrastructure to replace older, degrading metal pipes. The group estimates that there is currently four million kilometers of buried pipes and cables in the United Kingdom, of which 100,000 kilometers is in need of replacement.

The pipes in the ground at the moment are quite difficult to detect because existing methods are either too expensive or ineffective,” said Rakesh Roshan, a project manager at Oxford University’s technology arm, Isis Innovation. “Our device has a high level of accuracy and we expect it to reduce the cost of street works by at least 40 percent.”

Ellie Zolfagharifard writes that OXEMS’ solution uses a combination of radio-frequency identification and detection (RFID), and passive low-frequency tags that are attached to individual pieces of buried plastic pipe. These tags act as a barcode and, when scanned from surface, are able to provide information about the pipe’s location, its function and its state of health.

Professor David Edwards of the Department of Engineering Science led the founding team comprising Dr. Harvey Burd, Dr. Christopher Stevens, and Dr. Tong Hao that developed the technology at Oxford University. Edwards said: “We originally started working on the problems industry faced in this area as part of the ‘Mapping the Underworld’ call from the Engineering and Physical Sciences Research Council (EPSRC), which led to the domain ‘barcode’ approach. Our previous work in underwater pipe detection enabled us to model the response from wet environments and develop the OxEmS technology based on a long history of working on long range detection and positioning systems.”

Kevin Gooding, chief executive of OXEMS, said: “One of the major benefits to utility firm of the OSEMS solution is that the ’intelligent’ part of the technology is on the surface, so that the buried tagging units are simple, leading to significantly reduced unit costs, as well as increased reliability and longevity.”

Roshan added that the technology could be used in other applications, such as identifying contaminates in the water supply or detecting cracks in cement. Talks are currently underway with two major utilities and the technology is expected to be commercialized in the near future.