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Modelling The Leakage Rate And Reduction Using Minimum Night Flow Analysis
Published in Taha Mohammed AL-Washali, Water Loss Assessment in Distribution Networks: Methods, Applications and Implications in Intermittent Supply, 2021
Zarqa water network serves 160,000 customers (as in 2017) which accounts for approximately one million consumer based on an average of 6.3 people served per customer. About 57% of the water comes from some 99 groundwater wells while the remaining 43% is piped long-distance from the Disi aquifer. The length of the network mains (pipes > 100 mm) is 2,447 km according to the GIS records. These represent only 30% of the network, and the remaining 70% are service connections. Various pipe materials are used, including: polyethylene, galvanised iron, ductile iron, cast iron, and steel. The network is almost fully pumped with average pressures from 10 to 60 m, except for small sections of gravity or combined supply. The water is supplied to customers through interlinked distribution areas located within five administrative zones: Rusaifah, Al-Azraq, Beerian, AL-Hashimia, and Dhulail. The water supply in Zarqa is intermittent with an average of 36 hr per week, usually during 2 days in the week. The volume of non-revenue water (NRW) in Zarqa changes every year following the fluctuations of the production level of Zarqa water utility (AL-Washali et al. 2019a), but the unnormalised average NRW volume (over the last 10 years) is 29.2 ±7.1 million m3 per year, which accounts for 57% ±4% of the supplied water.
Classification of Steel
Published in Vladimir B. Ginzburg, Metallurgical Design of Flat Rolled Steels, 2020
Steel tubular products can be generally classified into the two broad classifications of tubes or pipes. Although the use of the terms pipe and tube is not always consistent, the term pipe is commonly used to describe cylindrical tubular products made to standard combinations of outside diameter and wall thickness. Pipe is also distinguished from tubing by the fact that it is produced in relatively few sizes and, therefore, in comparatively large quantities. Pipes can be divided into the following named use groups [3]: Standard pipeSpecial pipeLine pipeOil country tubular goodsWater well pipePressure pipe. Tubes can also be divided into the following named use groups: Pressure tubesStructural tubingMechanical tubing.
Corrosion
Published in Mavis Sika Okyere, Mitigation of Gas Pipeline Integrity Problems, 2020
In some circumstances, the most cost-effective and/or safest way to repair a pipeline defect is to remove the affected segment of pipe and replace it. Removal requires that the pipeline be shut down or that the affected segment be isolated and depressurized. When the pipeline is shut down, it is cleaned and flushed with an inert gas to remove crude oil and reduce any explosive conditions. To isolate the affected segment without removing the product, operators can shut valves on either end of the defective segment. Operators sometimes use a freeze plug for the same purpose. A freeze plug is a procedure that uses liquid nitrogen to freeze the product before and after the segment that is to be replaced. Once the product has been removed or isolated, the pipeline is cut out as a cylinder and replaced by an already hydrostatically tested pipe to ensure it can withstand the operating pressure. After the tie-in welds are inspected, the product flow may resume. Operators may elect to remove a pipeline, while the product is still in the line using a method known as a hot tie-in. By maintaining a low positive pressure in the pipeline, specially trained personnel can weld and cut the pipeline without explosions while igniting the escaping product. Removal repair is one of the costlier repair options; however, it is considered a permanent fix for any pipeline defect (Table 3.28).
Environmental assessment of construction and renovation of water distribution networks considering uncertainty analysis
Published in Urban Water Journal, 2020
Mohsen Hajibabaei, Sina Hesarkazzazi, Mayara Lima, Florian Gschösser, Robert Sitzenfrei
In WDNs, various factors such as operational (e.g., pressure management and installation conditions), environmental (e.g., temperature and soil moisture), and pipe-intrinsic factors (e.g., diameter and quality of materials) can influence the life span and failure rate of water pipes (Sanjuan-delmás et al. 2014; Barton et al. 2019). Because these factors vary for different cases, few reliable data can be found for the actual life span of water distribution pipe materials. Sanjuan-delmás et al. (2014) assumed a life span of 50 years for assessing the environmental impacts of 200 mm DI pipe with a design pressure of 10 bar. In addition, some studies have considered average life spans of PVC and HDPE to be 25 ± 5 and 40 ± 10 years, respectively (Morera et al. 2016). In this study, based on the information obtained from the TPWWC and pipe producers (TPWWC 2019), average life spans of 25 years, 50 years, and over 50 years were adopted for PVC, HDPE, and DI pipes, respectively.
Experimental study and numerical simulation of the influence of vent conditions on hydrogen explosion characteristics
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Ning Zhou, Peng-Fei Ni, Xue Li, Xu-Wei Li, Xiong-Jun Yuan, Hui-Jun Zhao
The experimental system used in this paper is shown in Figure 1. The experimental system was composed of experimental pipes, gas distribution system, vacuum pump, data acquisition system, and ignition device. The pipes were made of type 304 stainless steel. The inner diameter of the pipe was 125 mm. The wall thickness was 5 mm. The total length was 7.2 m. The maximum pressure that the pipe can withstand was 6 MPa. Pressure sensors (model CY400) and flame sensors (model CKG100) were installed on the pipe. P1 to P8 were pressure sensors and S1 to S9 were flame sensors. The distance of P1 to P8 pressure sensor to the ignition end was 0.75, 1.5, 2, 2.85, 3.6, 4.2, 5.2, and 6.2 m, respectively, and the distance of S1 to S9 flame sensor to the ignition end was 0.75, 0.95,1.5, 2, 2.85, 4.2, 5.2, 6.2, and 6.7 m, respectively. In order to ensure the air tightness of the pipe, tetrafluoro gaskets was used to seal the flange joint of the pipe. Eight operating conditions were carried out to analyze the influence of the position and number of the vent on the combustion and explosion characteristics of hydrogen-air premixed gas, as shown in Table 1. The vent was set at the top of the pipe and the diameter was 38 mm. The vent was sealed with film material which was made of polyethylene terephthalate during the experiment. The hydrogen-air premixed gas with a concentration of 29.6% (stoichiometric) was used in each test. The ignition mode was selected by high voltage pulse ignition, and the experimental ignition energy was 1 J. The experiment was carried out in spring, so the indoor temperature was kept at 15–20°C and the initial pressure was 0.1 MPa. Each experiment was repeated three times in each working condition to ensure the accuracy.
Development and thermodynamic analysis of a novel heat pipe vacuum tube solar collector with sensible heat storage
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Anshul Sachdeva, Chandrashekara M., Avadhesh Yadav
Flexible stainless steel (SS-304) hoses have been used to connect the components and guide the flow of HTF in the solar collector. These pipes can withstand a temperature up to 400°C. The headers, sump, and rotary gear pump are connected in series with the connecting pipes using hexagonal bolts press fitted into the pipe ends. The pipes are insulated to minimize convective heat loss to the surroundings.