Water and Effluent Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/917412
Putting the pressure on leakage With traditional leakage detection techniques having failed, could PIPA's inspection technology do the trick? This had a major knock-on e ect, as the client could not proceed with a localised repair solution, and a road closure of the main carriageway may also have been required. Upstream losses were identi• ed as 2Mld however the client needed to fully understand its pipe con- • guration and also undertake a full internal leakage sweep. The client installed a through-bore style • re hydrant for API to undertake an internal pressurised pipe assessment. API uses PIPA technology that includes a pressure rated camera – the Hydrocam – and a hydrophone capsule (Pipe- pod) tethered to a 105m semi rigid rodding to give the opera- tor live video and recorded audio data during an inspection. The system enters a pipe- line via a 2in tapping, and is fully chlorinated during its insertion using a registered designed seal housing; the sys- tem works on a live basis, with no interruptions to customers services and with several sur- veys undertaken this innova- tive product can cover a dis- tance of up to 1km a day. The technology, available from PIPA (Pipe Inspection Products & Accessories), is the latest live water main inspec- tion system on the market being fully battery-powered and only requires a two-man team for its implementation. During the survey a full leakage sweep was undertaken with no leak identi• ed, how- ever an unknown pipe branch was located with heavy water Š ow identi• ed. API successfully delivered a full leakage sweep of the asset, and also identi• ed an unknown 6in pipe branch. All were later validated by client. The tethered insertion technol- ogy system also allowed for precise identi• cation of the unknown branch location. The acoustic system is very responsive, and the operator was able to identify that the missing 2Mld was not a leak- age issue. The client traced back the pipe branch identi- • ed and isolated a buried valve which in turn resolved the water loss issue. It would have been very dif- • cult and expensive for con- tractor to • nd the remaining issues within the water main. The CCTV and acoustic capa- bility proved indispensable for locating issues and trouble shooting. API completed the inspec- tion in one working day, and o ered a full solution identify- ing true pipe con• guration and ONSITE LEAKAGE DETECTION also by ruling out leakage issues. The contractor resolved the ongoing issue by removing the guess work at a fraction of the cost and time invested in other methods in previous weeks. A spokesman for API says the project was a great S ervice delivery company API was contacted recently by a UK water utility client which had identi• ed a leak on a cast iron pipeline in a sensitive tra" c area. The water company, using traditional techniques, could not fully understand the issue or pinpoint the leak's exact location. The pipeline is an old 9in CI pipe with 3bar pressure and was installed more than 50 years ago with unmapped location and con• guration. The client utilised an in-house leakage team and searched for leaks over several months with the following methods: • Noise correlators: four leaks were identi• ed along the main. However, these resulted in four dry dig excavations • Listening stick: the pipe- line was sited below a busy tra" c carriageway so this technique was not feasible 8 WET NEWS JANUARY 2018 success, ideal due to pipe loca- tion and material and also a great case study for the com- pany. "The contractor had exhausted all other pipeline inspection avenues, and was more than relieved when we o ered a solution." PROJECT SPECS Identify and locate a leak on a cast iron pipeline Prevent 2Mld upstream losses Prevent road closure while carrying out work TECHKNOW A pressure rated camera – the Hydrocam – and a Pipepod hydrophone capsule were used These were tethered to a 105m semi rigid rodding to give live video and recorded audio data during the inspection The system enters a pipeline via a 2in tapping, and is fully chlorinated during its insertion THE VERDICT "The contractor had exhausted all other pipeline inspection avenues, and was more than relieved when we o' ered a solution" API NEED TO KNOW 1 The pipeline is an old 9in CI pipe with 3bar pressure and was installed more than 50 years ago 2 A full leakage sweep was undertaken with no leak identi— ed 3 A through-bore style — re hydrant was installed for an internal pressurised pipe assessment