Investigations into decoating and recycling of pipeline elements using the on-site high-pressure water jet technique

Author(s):  
A W Momber

The paper describes investigations into the application of the high-pressure water jet technique for the recycling of coated pipeline elements. The paper starts with the introduction and definition of the process parameter 'selectivity'. After this, a review about the general principles of jet cutting technology, including tools, is given. Finally, the author reports on the decoating and demolition of covered steel pipes by plain and abrasive water jets. High-pressure water jets are versatile tools for the complete and partial decoating of steel pipes. Abrasive water jets can be used successfully to cut steel pipes including different coating systems.

2006 ◽  
Vol 120 (7) ◽  
pp. 600-601 ◽  
Author(s):  
M Ahmad ◽  
K Midwinter ◽  
R Capper

We report a case of upper airway obstruction following high-pressure water jet injury to the pharynx incurred from a car wash jet. Injuries from high-pressure water jets are relatively rare and, to the best of our knowledge, airway obstruction as a result has not been reported. Since this unusual injury may be associated with life-threatening complications, it must be promptly recognized and treated.


2020 ◽  
Vol 12 (10) ◽  
pp. 168781402096229
Author(s):  
Jinliang Zhang ◽  
Yongchang Li ◽  
Yuansheng Zhang ◽  
Fengwei Yang ◽  
Chao Liang ◽  
...  

The concept of tunnel boring machine (TBM) disc cutter rock breaking coupled with high-pressure water jets has been proposed to overcome the difficulties that occur when TBMs encounter extremely hard rocks. Thus, to meet actual engineering requirements for the TBM construction of tunnels as part of the Wan’anxi water diversion project in Longyan City (Fujian Province, China), experiments were conducted on high-pressure water jet-assisted TBM disc cutter rock breaking. By varying kerf depth and width under different water jet parameters and performing disc cutter rock breaking tests on rock surfaces with no kerf, single kerf, and double kerfs, the effects of different kerf depths on the disc cutter rock breaking process, load, and efficiency were examined. The test results showed that high-pressure water jets can generate the regular kerfs required for the coupled disc cutter rock breaking of granite. Employing the coupled rock breaking method also resulted in a decrease in specific energy and an approximately 40% decrease in the normal force of the disc cutter, thereby significantly improving rock breaking efficiency. These results provide key technical parameters for the design and manufacture of high-pressure water jet-assisted rock-breaking TBMs and serves as a reference for similar processes.


2012 ◽  
Vol 557-559 ◽  
pp. 2221-2224 ◽  
Author(s):  
Hua Lin Liao

It is important to make sure the stress distribution in the media under high pressure water jet as to improve jets utilities. A numerical analyzing model of stress distribution about interaction of high pressure water jets impinging solid material is established according to fluid-structure interaction theory. Standard k-ε equations model and controlled volume method for the water jets, and elastic orthotropic continuum and finite element method for the solid are adopted. The stress distributions in the fluid field and inside solid material with different water jetting velocities were computed using the model and method. Numerical results show that the stress distributes obviously on the part solid material under water jets impingement. The impinging area is subjected to compression stress, and the maximum tensile stress is located on impacting surface and the maximum shear stress being under impacting center about half nozzle diameter away. It concludes that by controlling the jet velocity and distance, jet cutting, breaking, decoating, surface processing efficiencies could be improved.


2021 ◽  
Vol 14 (13) ◽  
Author(s):  
Zeng-qiang Yang ◽  
Chang Liu ◽  
Feng-shuo Li ◽  
Lin-ming Dou ◽  
Gang-wei Li ◽  
...  

1988 ◽  
Vol 4 (4) ◽  
pp. 340-343 ◽  
Author(s):  
John H. Posselius ◽  
Jr.. Glenn T. Conklin

2011 ◽  
Vol 462-463 ◽  
pp. 774-779
Author(s):  
Hu Si ◽  
Xiao Hong Li ◽  
Yan Ming Xie

The high pressure waterjet is widely applied for mine industry, mechanical manufacture, environmental engineering, and medicine field due to its particular characteristic. Recently, the application of high pressure waterjet for gas drainage in mine has been receiving increasing attention with the development of exploitative technology. The micro-damage mechanism of coal under high pressure water jet is key to drain gas effectively. Based on damage mechanics and rock dynamics, the paper analyzed the micro-structure deformation and damage of rock and the impulsive effect under high pressure water jet and developed the dynamic model. Further, on the assumption of that rock was homogeneous and isotropic, a computational model was established based on the Arbitrary Lagrangian Eulerian (ALE) fluid-solid coupling penalty function method. The rock damage under high pressure water jet was simulated by the dynamic contact method. The results showed that the damage and breakage of ruck was mainly attributed to impacting effect and was characterized by local effect, and the evolvement of rock breakage went through three stages and the figure of rock breakage trended a funnel. On the whole, numerical results agreed with experimental results.


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