Study on the pressure pipe length in train aerodynamic tests and its applications in crosswinds

2022 ◽  
Vol 220 ◽  
pp. 104880
Author(s):  
Tang-Hong Liu ◽  
Lei Wang ◽  
Zheng-Wei Chen ◽  
Hong-Rui Gao ◽  
Wen-Hui Li ◽  
...  
Keyword(s):  
Pipe Length ◽  
Pressure Pipe

The Parameter Performances and Simulations of Nitrogen-Inflating Hydraulic Breaker Based on AMESim

2014 ◽  
Vol 988 ◽  
pp. 625-629
Author(s):  
Yu Wan Cen ◽  
Liang Wu ◽  
Xiao Hua Ye ◽  
Ye Ye
Keyword(s):  
Flow Rate ◽  
Concrete Structure ◽  
Hydraulic System ◽  
Theoretical Foundation ◽  
Entire System ◽  
Pipe Length ◽  
Pressure Pipe ◽  
Pressure Feedback ◽  
Working Principle ◽  
At Home

After analyzing the technology of hydraulic breakers at home and abroad, this paper develops a new nitrogen-inflating hydraulic breaker based on the pressure feedback. Its concrete structure, the working principle and the hydraulic system are discussed. Then the entire system is built and simulated by using AMESim software. Impact performances are studied when some factors such as feedback pressure, pipe length and flow rate are changed. With all the achievements mentioned above, it provides a theoretical foundation for a further understanding of the hydraulic breaker.

Design of Prestressed Concrete Pressure Pipe

PCI Journal ◽  
1965 ◽  
Vol 10 (4) ◽  
pp. 69-82
Author(s):  
Harold V. Swanson
Keyword(s):  
Prestressed Concrete ◽  
Pressure Pipe

EXPERIMENTAL STUDY ON FLAME PROPAGATION IN A STRAIGHT PIPE

2016 ◽  
Vol 78 (8-3) ◽  
Author(s):  
Siti Zubaidah Sulaiman ◽  
Rafiziana Md Kasmani ◽  
A. Mustafa
Keyword(s):  
Experimental Study ◽  
Flame Propagation ◽  
Experimental Work ◽  
Diameter Ratio ◽  
Straight Pipe ◽  
Pipe Length ◽  
Operating Condition ◽  
Consistent Trend ◽  
Length To Diameter Ratio

Flame propagation in a closed pipe with diameter 0.1 m and 5.1 m long, as well as length to diameter ratio (L/D) of 51, was studied experimentally. Hydrogen/air, acetylene/air and methane/air with stoichiometric concentration were used to observe the trend of flame propagation throughout the pipe. Experimental work was carried out at operating condition: pressure 1 atm and temperature 273 K. Results showed that all fuels are having a consistent trend of flame propagation in one-half of the total pipe length in which the acceleration is due to the piston-like effect. Beyond the point, fuel reactivity and tulip phenomenon were considered to lead the flame being quenched and decrease the overpressures drastically. The maximum overpressure for all fuels are approximately 1.5, 7, 8.5 barg for methane, hydrogen, and acetylene indicating that acetylene explosion is more severe. 

Comparison of the Limit Loads Between Defected Pressure Pipes With an Internal Pit and an External Pit at High Temperature

2013 ◽  
Author(s):  
Changyu Zhou ◽  
Bo Wang ◽  
Zhigang Sun ◽  
Jilin Xue ◽  
Xiaohua He
Keyword(s):  
High Temperature ◽  
Power Plants ◽  
Structural Integrity ◽  
Load Condition ◽  
Relative Length ◽  
Limit Load ◽  
Relative Depth ◽  
Corrosive Media ◽  
Pressure Pipe ◽  
Pressure Pipes

High temperature pressure pipes are widely used in power stations, nuclear power plants, and petroleum refinery, which always bear combined effects of high temperature, high pressure, and corrosive media, so the local pits are the most common volume defects in pressure pipe. Due to various reasons, the defects usually appear on the internal or external wall of pipe. In this paper, the dimensions of a defect were characterized as three dimensionless factors: relative depth, relative gradient and relative length. The main objects of study were the pipe with an internal pit and pipe with an external pit. Orthogonal array testing of three factors at four different levels was applied to analyze the sequence of the influence of three parameters. In present study, when the maximum principal strain nearby the location of the defects reaches 2%, the corresponding load is defined as the limit load, which is classified as two kinds of load type: limit pressure and limit bending moment. According to this strain criterion and isochronous stress strain data of P91 steel, the limit load of high temperature pipe with a local pit was determined by using ABAQUS. And in the same load condition of the pipe with the same dimensionless factors, the limit load of the internal defected pipe was compared with that of the external defected pipe. The results of this study can provide a reference for safety assessment and structural integrity analysis of high temperature creep pressure pipe with pit defects.

scholarly journals Residual Stress State of X65 Pipeline Girth Welds Before and After Local and Furnace Post Weld Heat Treatment

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Yao Ren ◽  
Anna Paradowska ◽  
Bin Wang ◽  
Elvin Eren ◽  
Yin Jin Janin
Keyword(s):  
Heat Treatment ◽  
Residual Stress ◽  
Residual Stresses ◽  
Outer Surface ◽  
Post Weld Heat Treatment ◽  
Pipe Length ◽  
Stress Profiles ◽  
Girth Welds ◽  
Welded Pipe ◽  
Weld Heat

This research investigated the effects of global (in other words, furnace-based) and local post weld heat treatment (PWHT) on residual stress (RS) relaxation in API 5L X65 pipe girth welds. All pipe spools were fabricated using identical pipeline production procedures for manufacturing multipass narrow gap welds. Nondestructive neutron diffraction (ND) strain scanning was carried out on girth welded pipe spools and strain-free comb samples for the determination of the lattice spacing. All residual stress measurements were carried out at the KOWARI strain scanning instrument at the Australian Nuclear Science and Technology Organization (ANSTO). Residual stresses were measured on two pipe spools in as-welded condition and two pipe spools after local and furnace PWHT. Measurements were conducted through the thickness in the weld material and adjacent parent metal starting from the weld toes. Besides, three line-scans along pipe length were made 3 mm below outer surface, at pipe wall midthickness, and 3 mm above the inner surface. PWHT was carried out for stress relief; one pipe was conventionally heat treated entirely in an enclosed furnace, and the other was locally heated by a flexible ceramic heating pad. Residual stresses measured after PWHT were at exactly the same locations as those in as-welded condition. Residual stress states of the pipe spools in as-welded condition and after PWHT were compared, and the results were presented in full stress maps. Additionally, through-thickness residual stress profiles and the results of one line scan (3 mm below outer surface) were compared with the respective residual stress profiles advised in British Standard BS 7910 “Guide to methods for assessing the acceptability of flaws in metallic structures” and the UK nuclear industry's R6 procedure. The residual stress profiles in as-welded condition were similar. With the given parameters, local PWHT has effectively reduced residual stresses in the pipe spool to such a level that it prompted the thought that local PWHT can be considered a substitute for global PWHT.

Pipe stick problems of deep well drilling

2021 ◽  
Vol 66 (05) ◽  
pp. 192-195
Author(s):  
Rövşən Azər oğlu İsmayılov ◽  
Keyword(s):  
Drilling Fluid ◽  
Drill Pipe ◽  
Drill String ◽  
Differential Pressure ◽  
Drilling Mud ◽  
Fluid Circulation ◽  
Well Drilling ◽  
Deep Well ◽  
Pressure Pipe ◽  
Bottomhole Pressure

The aricle is about the pipe stick problems of deep well drilling. Pipe stick problem is one of the drilling problems. There are two types of pipe stick problems exist. One of them is differential pressure pipe sticking. Another one of them is mechanical pipe sticking. There are a lot of reasons for pipe stick problems. Indigators of differential pressure sticking are increase in torque and drug forces, inability to reciprocate drill string and uninterrupted drilling fluid circulation. Key words: pipe stick, mecanical pipe stick,difference of pressure, drill pipe, drilling mud, bottomhole pressure, formation pressure

Research of the flow procedures in a pressure sewer system

2003 ◽  
Vol 47 (7-8) ◽  
pp. 351-356
Author(s):  
C. Dohse ◽  
H. Eckstädt
Keyword(s):  
Land Reclamation ◽  
Flow Conditions ◽  
Sewer System ◽  
Flow Meters ◽  
Initial Information ◽  
Pressure Pipe ◽  
Pumping Stations ◽  
Hydraulic Conditions ◽  
Measuring Section ◽  
The University

At the Institute of Land Reclamation, Hydrology and Sanitary Engineering of the University at Rostock the pressure and flow ratios are examined within a measuring section in the pressure dewatering system on the Darfl peninsula. The objective of the research project is the knowledge upgrade about the highly unsteady hydraulic conditions in a pressure sewer system. This paper firstly presents the method and the dimensioning of pressure dewatering systems, which can be done using either the peak effluent method or the statistical method; the examination program will be explained. The examination includes pressure difference measuring with two pressure meters and flow data measuring via magnetic-inductive flow meters. Additionally the pump running times of 15 pumping stations, as well as the compressor action of the pressure pipe rinsing station are continuously and temporarily recorded and saved. Finally the measuring results which provide initial information about the pressure and flow conditions in a pressure dewatering system will be presented. The effects of the rinsing, the low pressure differences, the air cushions, the seasonal differences as well as the daily development graphs of the wastewater production are all clearly visible.

Exhaust-Pipe Effects in a Single-Cylinder Four-Stroke Engine

1940 ◽  
Vol 143 (1) ◽  
pp. 109-127 ◽  
Author(s):  
G. F. Mucklow
Keyword(s):  
Full Range ◽  
Exhaust Pipe ◽  
Valve Timing ◽  
Pipe Length ◽  
Exhaust Port ◽  
Single Cylinder ◽  
Wide Range ◽  
Different Diameters ◽  
Theoretical Considerations ◽  
Stroke Engine

The paper deals with an investigation of the fluctuations of pressure, due to piston motion on the exhaust stroke, which occur in the exhaust pipe of a single-cylinder four-stroke engine. Indicator diagrams of exhaust-port and of cylinder pressure, and measurements of air consumption were recorded, using exhaust pipes of three different diameters at three standard engine speeds; the exhaust pipe length was varied over a wide range in each case. In the light of the data thus obtained, the effects on air consumption of progressive alterations in valve timing were studied under known conditions of exhaust port pressure. Further trials were then carried out in which the valve timing which gave the maximum air consumption was determined for the full range of conditions of speed and exhaust pipe dimensions. The experimental results are discussed, and a method is derived by which the pressures in the exhaust port throughout the cycle may be obtained from theoretical considerations; the method is also directly applicable to induction pipe conditions.

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