Specification for polyethylene pipes (type 50) in metric diameters for general purposes

1984 ◽  
Keyword(s):  
2017 ◽  
Vol 3 (3) ◽  
pp. 77-80
Author(s):  
V.V. Kovriga ◽  
V.G. Kolbaya ◽  
T.F. Oreshenkova ◽  
N.V. Prokopev ◽  
D.A. Chernikov ◽  
...  
Keyword(s):  

2021 ◽  
Vol 1827 (1) ◽  
pp. 012108
Author(s):  
Lv Hai-zhou ◽  
Sun Ming ◽  
Xu Yu-bin ◽  
Wu Yun ◽  
Sun Long-long

2009 ◽  
Vol 131 (6) ◽  
Author(s):  
Jianfeng Shi ◽  
Jinyang Zheng ◽  
Weican Guo ◽  
Ping Xu ◽  
Yongquan Qin ◽  
...  

With the increasing application of electrofusion (EF) welding in connecting polyethylene (PE) pipes for gas distribution, more effort has been invested to ensure the safety of the pipeline systems. The objective of this paper is to investigate and understand the temperature distribution during EF welding. A one-dimensional transient heat-transfer model was proposed, taking the variation in the rate of power input, the phase transition of PE, and the thermal contact conductance between heating wire and PE into consideration. Then, experiments were designed to verify the power input and the temperature. The measured values of the power input were shown to be in good agreement with the analytical results. Based on ultrasonic test (UT), a new “Eigen-line” method was presented, which overcomes the difficulties found in the thermocouples’ temperature measurements. The results demonstrate good agreements between prediction and experiment. Finally, based on the presented model, a detailed parametric study was carried out to investigate the influences of the variation in the power input, the physical properties of PE, and the thermal contact conductance between heating wire and surrounding PE.


2020 ◽  
pp. 46-52
Author(s):  
N.P. Aleshin ◽  
D.M. Kozlov ◽  
L.YU. Mogilner

The reliability of ultrasonic testing (UT) of the quality of welded joints of polyethylene pipelines, made end-to-end with a heated tool, is considered in comparison with mechanical tests and radiography. The greatest detection of solid defects is provided by ultrasonic inspection with the use of chord tipe probes (not less than 90 %). When detecting defects translucent for ultrasound (lack of penetration, lack of fusion, etc.), the reliability decreases to 70÷80 %. Keywords: welding, polyethylene pipeline, quality control, ultrasonic testing, chord tipe probe. [email protected]


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