FIRE WATER NETWORK LOSS INVESTIGATION
According to the contract on business and technical cooperation between NMAqua sp Banja Luka and Hydra d.o.o Sarajevo, during November, a fault test was performed on the water supply network for fire protection. After the determined loss of the pipeline for fire protection on the section of the highway A1 Sarajevo - Mostar, we were hired by our business partners to carry out an inspection, inspection and try to find the problem.
It was about a section of the 110mm pipeline with a length of about 600m, where it was determined that there was a loss by manipulating the sector closures. For this work, it was necessary for us to have an ultrasonic flow meter and an acoustic sound detector - a geophone.
After we let water into the pipeline, which was closed, through the reduction valve, we got a pressure that was satisfactory for working with the geophone. We were informed by colleagues who had done preliminary preparation in terms of determining the part of the pipeline where there is a large loss, that by releasing that part of the network, the tank empties very quickly.
Because of all the above, it was important for us to carry out the inspection and investigation of losses as soon as possible.
In order to get the most accurate picture of the situation and narrow the circle to the shortest possible distance, we first measured the flow with an ultrasonic flow meter at several measuring points along the mentioned section of 600 mm.
When we determined the approximate location of a possible uncontrolled discharge, because we received information on the flow meter about the size of the discharge of about 18.00 m³/h, we listened to that part of the pipeline.
The specificity was that a good part of the section for which we assumed that there was a pipeline protrusion was under the viaduct, past which the road for one part of the settlement passed. By controlling the noise on the pipeline with an acoustic detector, we found a very weak noise and a small vibration on the bridge in a length of about ten meters.
Given the location of the failure, it was clear that a visual inspection of the pipe, which was placed on the supports for the structure on the underside of the bridge, had to be carried out, because the outflow of water would have to be visible.
Through visual inspection, we determined during the tour that it was a protrusion from the 50 mm profile pipe, which served as a winter outlet for the discharge of the hydrant fire protection pipeline. There was a 2" valve ball rupture at the end of the pipe and therefore an uncontrolled discharge, which was difficult to see from a greater distance due to its position next to the concrete pillar of the bridge.
Given the circumstances that we had to react quickly due to time constraints and emptying the tank, we had another very successfully completed job behind us.
