Gradient Structures in Thin-Walled Metallic Tubes Produced by Continuous High Pressure Tube Shearing Process

2017 ◽  
Vol 19 (11) ◽  
pp. 1700345 ◽  
Author(s):  
Rimma Lapovok ◽  
Yuanshen Qi ◽  
Hoi P. Ng ◽  
Laszlo S. Toth ◽  
Yuri Estrin
Keyword(s):  
High Pressure ◽  
Pressure Tube ◽  
Thin Walled

Innovative Manufacturing Process for Defect Free, Affordable, High Pressure, Thin Walled, Hydraulic Tubing

2010 ◽  
Vol 20 (7) ◽  
pp. 1206-1218 ◽  
Author(s):  
W. Miranda ◽  
G. Takiguchi ◽  
T. Shimabukuro ◽  
L. McLennan ◽  
C. Agajanian ◽  
...  
Keyword(s):  
High Pressure ◽  
Manufacturing Process ◽  
Thin Walled

Repair of Leaks in Thin Wall High Pressure Pipelines Using Composite Reinforcing Technologies

2020 ◽  
Author(s):  
Chris Alexander ◽  
Salem Talbi ◽  
Richard Kania ◽  
Jon Rickert
Keyword(s):  
High Pressure ◽  
Operating Conditions ◽  
Thin Wall ◽  
Nitrogen Gas ◽  
Composite Repair ◽  
Pressure Cycling ◽  
Thin Walled Pipe ◽  
Corrosion Defects ◽  
Thin Walled ◽  
Pipe Materials

Abstract A study was conducted to evaluate two composite repair technologies used to reinforce severe corrosion and thru-wall leaking defects in thin-walled pipe materials; conditions where the welding of conventional Type B steel sleeves cannot be conducted. This program involved the reinforcement of simulated 85% corrosion defects in 6.625-inch × 0.157-inch, Grade X52 pipe materials subjected to cyclic pressure and burst testing. The test matrix also included repaired pipe samples with thru-wall defects that were pressurized using nitrogen gas and buried for 90 days. The program was comprehensive in that it evaluated the following elements involving a total of 81 reinforced corrosion defects. • Corrosion features with a depth of 85% of the pipe’s nominal wall thickness in thin-walled pipe material (i.e., 0.157 inches, or 4 mm). • Thru-wall defects having a diameter of 0.125 inches (3 mm). • Repairs made with leaking defects having 100 psig (690 kPa) internal pressure. • Strain gage measurement made in non-leaking 85% corrosion defects; it should be noted that the remaining “15%” ligament was 0.024 inches (0.6 mm); to the author’s knowledge, no high-pressure testing has ever been conducted on such a thin remaining wall. • Long-term 90-day test that included pressurization with nitrogen gas, followed by relatively aggressive pressure cycling up to 80% SMYS followed by burst testing. This is the first comprehensive study conducted by a major transmission pipeline operator evaluating the performance of competing composite technologies used to reinforce severe corrosion features with thru-wall defects. The reinforcement of leaks has not been accepted by regulatory bodies such as the Canadian Energy Regulator (CER), or the U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA). A goal of the current study is to validate composite repair technologies as a precursor to regulatory approval. The results of this study indicate that viable composite repair technologies exist with capabilities to reinforce leaks in pipelines that experience operating conditions typical for gas transmission systems (i.e., minimal pressure cycling).

Vibration resistant high pressure tube fitting

1987 ◽  
Vol 81 (2) ◽  
pp. 581-581
Author(s):  
Leonard J. Kowal ◽  
Albert J. Schwarz
Keyword(s):  
High Pressure ◽  
Pressure Tube

Stress and strain gradients in high-pressure tube twisting

2012 ◽  
Vol 66 (10) ◽  
pp. 773-776 ◽  
Author(s):  
A. Pougis ◽  
L.S. Tóth ◽  
O. Bouaziz ◽  
J-J. Fundenberger ◽  
D. Barbier ◽  
...  
Keyword(s):  
High Pressure ◽  
Pressure Tube ◽  
Stress And Strain ◽  
Strain Gradients

Numerical and Experimental Damping Assessment of a Thin-Walled Friction Damper in the Rotating Set-Up With High Pressure Turbine Blades

2006 ◽  
Author(s):  
J. Szwedowicz ◽  
C. Gibert ◽  
T. P. Sommer ◽  
R. Kellerer
Keyword(s):  
High Pressure ◽  
Contact Stiffness ◽  
Turbine Blades ◽  
Mode Shapes ◽  
Friction Damper ◽  
High Pressure Turbine ◽  
Friction Forces ◽  
Normal Contact ◽  
Contact Behaviour ◽  
Thin Walled

Under-platform friction dampers are preferably solutions for minimizing vibrations of rotating turbine blades. Solid dampers, characterized by their compact dimensions, are frequently used in real applications and often appear in patents in different forms. A different type of the friction damper is a thin-walled structure, which has larger dimensions and smaller contact stresses on a wider contact area in relation to the solid damper. The damping performance of a thin-walled damper, mounted under the platforms of two rotating, freestanding high pressure turbine blades is investigated numerically and experimentally in this paper. The tangential and normal contact stiffness, that are crucial parameters in optimal design of each friction damper, are determined from three-dimensional finite element (FE) computations of the contact behaviour of the thin-walled damper on the platform including friction and centrifugal effects. The computed contact stiffness values are applied to non-linear dynamic simulations of the analysed blades with the friction damper of a specified mass. These numerical analyses are performed in the modal frequency domain with a code, which is based on the Harmonic Balance Method (HBM) for the complex linearisation of friction forces. The blade vibrations are characterised by a set of the lowest FE mode shapes of one freestanding blade without damper. The dynamic results of the calculated blades with the damper are in good agreement with the measured data of the real mistuned system. In the analysed excitation range, the numerical performance curve of the thin-walled damper is obtained within the scatter band of the experimental results. For the known friction coefficients and available FE and HBM tools, the described numerical process confirms its usability in the design of under-platform dampers.

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