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Runoff and Rainwater Harvesting
Published in Abrar Yousuf, Manmohanjit Singh, Watershed Hydrology, Management and Modeling, 2019
Junaid N Khan, Rohitashw Kumar, Abrar Yousuf
The crest gauge is designed to measure peak discharge in a channel reach during a flood event (Murthy 2013). A crest gauge consists of an ordinary staff gauge of sufficient width, to fit into a 2-inch galvanized pipe. This galvanized pipe is fitted with threaded pipe caps on either end. The holes of approximate diameter 0.25 inch are drilled in the galvanized pipe. The pipe is the installed vertically in the channel such that the bottom of the pipe is at the datum or bed of the stream. The staff gauge is inserted at the top of the pipe along with about a capful of ground cork and the top ventilated pipe cap is replaced. When the water flows in the channel, water enters through the lower holes and rises in the pipe and carries the ground cork with it. At the highest stage, the cork adheres to the wetter staff. As the water recedes, a visual record of the highest stage is indicated by the cork adhering to the staff. The operator only needs to remove the stall, read the high stage and wipe the staff clean for additional use (http://ecoursesonline.iasri.res.in).
Experiences with Modern Thread Lubricants
Published in A Strang, Performance of Bolting Materials in High Temperature Plant Applications, 2020
The paste has been tested in exhaust bends and pipes of diesel engines. Requirements of the thread paste include low levels of sulphur and halogens, a low scatter of friction coefficient and a friction level at a value which prevents self-loosening of nuts. The temperature of the bolts has been recorded as high as 600°C. The new paste fulfilled all these requirements and was specified to be used on connecting rods and threads of exhaust pipes and bends. In the chemical industry devices are being used to grow single crystals of silicon. The lubricants used on threads have to be ultra-pure and free of any metal. The temperature of the thread was 400°C. The new paste was tested here and was found to be suitable.In pyrolitic devices in the chemical industry, bolt temperatures as high as 950°C are found. In this case, performance at high temperature and high purity level was required. The ultra-pure paste passed these requirements and was approved.In aluminium motor blocks a threaded pipe is being screwed into pipe holes. The temperature in this case is 450°C. The lubrication of the aluminium threads posed a problem. The ultra-pure paste was used to successfully lubricate the aluminium threads at this temperature.Turbines operating at a temperature of 540°C also have to be lubricated by a high performance ultra-pure paste. Subsequently, threads could be disassembled, without any seizure, after a period of 6 months.
Transformer Installation and Maintenance
Published in Leonard L. Grigsby, Electric Power Transformer Engineering, 2017
Any oil leaks observed during mechanical maintenance should be corrected as these are the primary source for moisture and oxygen exchange with the insulation system. Leaks often originate from one of three sources as follows: Threaded pipe fittingsGasketing including valve packing glandsWelds
In-profile monitoring for cluster-correlated data in advanced manufacturing system
Published in Journal of Quality Technology, 2023
Peiyao Liu, Juan Du, Yangyang Zang, Chen Zhang, Kaibo Wang
In this case study, a motor drives a threaded pipe to tighten into a casing, where a spring is installed for buffering. Three sensors located on a backup tong are used to collect key process variables during the screw turning process, i.e., the number of turns, torque signal, and rotating speed signals. The first two sensors (S1 and S2) measure the mechanical deformation of the spring, which can be theoretically represented by the linear relationship between the number of turns (S1) and the torque (S2). Therefore, the intercept and slope of the fitted curve by S1 w.r.t S2 can be considered as two identified latent states of the process. In addition, it is the system power that influences the rotating speed (S3) which records the electrical property, and thus the system power is the third latent state. According to this domain knowledge, the state dimension is set to be three. In the actual manufacturing process, anomalies happen occasionally due to stripping of threads or slipping of pressure joints. This will influence the physical dynamics of the spring, which is further reflected in sensor signals. We have 98 IC samples and three OC samples, with slope shifts in S1 and S2, and step shifts in S3 since as Figure 1(b) shows. It should be noted that for different samples, their profile lengths vary from 350 to 650 due to unavoidable variations from the pre-tightening stage. For more detailed information about the background, please refer to Du et al. (2018).
Manufacturing a telescopic tube screw using a hydroforming process
Published in Materials and Manufacturing Processes, 2019
Hui Seok Jeong, Jae Hyun Ra, Sang Wook Han, Young Hoon Moon
Screw threads and threaded pipe joints have been widely used in heat exchangers, petroleum, mining, and civil structures.[12–15] A telescopic tube screw is a device that can provide an adjustable length feature and has been used in various applications for a secure and perfect fit. A variety of forming methods have been established for fabricating threaded and spiral parts. The screw is typically formed from a solid piece of material into desired rough shapes, and then machined into precise final desired shapes. Certain alternative methods, including roll-forming,[16,17] multi-stage cold forming,[18,19] and cross-wedge rolling of tubes,[20,21] have been used to form threaded and spiral parts. Table 1 compares different manufacturing processes to form threaded parts. As shown in the table, each manufacturing process is characterized by its own strengths and weaknesses, and because the formed product is significantly influenced by the manufacturing method, a reasonable compromise between process efficiency and product quality is required. The fabrication of threaded screw parts by using THF has been investigated due to its advantages of high efficiency, dimensional accuracy, and significant cost savings.