Protective Air Vessels for Rising Pipe Lines

1945 ◽  
Vol 153 (1) ◽  
pp. 15-23 ◽  
Author(s):  
A. M. Binnie

A long rising pipe line should be protected against the damage due to shock (or “water hammer”) which might ensue if the pumps suddenly failed. The most satisfactory method is to fit an air vessel on the delivery side of the pumps. The connexion between the air vessel and the pipe line should be constricted so that the oscillations of the water-level in the air vessel are damped. An approximate method is described in the paper for calculating the maximum expansion and pressure of the air, and its predictions are shown to be in satisfactory accord with experiment. The onset of water hammer, observed when damping was carried too far, was found to occur at velocities somewhat greater than theory suggests.

CORROSION ◽  
1958 ◽  
Vol 14 (8) ◽  
pp. 37-38

Abstract Recommended minimum characteristics of an asphalt wrapped underground pipe line coating system are given. Included are physical characteristics of primer, enamel and wrapping, testing methods for primer and enamel. 6.4.5


1937 ◽  
Vol 4 (2) ◽  
pp. A68-A74
Author(s):  
G. B. Karelitz ◽  
J. H. Marchant

Abstract The authors present a method for the numerical computation of the end forces and couples in a three-dimensional pipe line. The method takes care of a pipe line with any number of straight parts connected by bends. A procedure of computation is also shown when parts of the pipe line are skewed. The ends of the line may be partially or completely constrained against rotation and translation. A construction for the analysis of stresses in the pipe bends is given. The method is illustrated by a sample computation of the end forces and couples in a steam main which is restrained against thermal expansion.


Author(s):  
Robert A. Leishear

Water hammer during multi-phase flow is rather complex, but in some cases an upper limit to the pressure surge magnitude during water hammer can be estimated. In the case considered here, a two mile long pipeline with a single high point was permitted to partially drain. Due to gravitational effects, air bubbles up through the pipe line to its highest point, but the time required for air to reach the top of the pipe is rather long. Consequently, some transients caused by valve operations are affected by air entrapment and some are not. The intent of this research was to investigate the complex interactions between air, water vapor, and liquid during water hammer in a long pipe with one end of the pipe open to atmospheric conditions. To understand the system dynamics, experimental data was obtained from a long pipeline with an open end and also from a short, transparent tube. Transient calculations were performed for valve closures and pump operations as applicable. The limitations of available calculation techniques were considered in detail.


1984 ◽  
Vol 27 (228) ◽  
pp. 1182-1187
Author(s):  
Eiji KATO ◽  
Minoru SUITA ◽  
Masaaki KAWAMATA ◽  
Masumi YUDA

Irriga ◽  
2007 ◽  
Vol 12 (4) ◽  
pp. 439-455 ◽  
Author(s):  
Camilo De Lelis de Andrade ◽  
Bruno Leite Teixeira Perroni ◽  
Paulo Emílio Pereira de Albuquerque ◽  
Gabriel Roberto Oliveira ◽  
Fernando Falco Pruski ◽  
...  

DESENVOLVIMENTO E AVALIAÇÃO DE DISPOSITIVOS DE CONTROLE DE VAZÃO DERIVADA EM CANAIS DE IRRIGAÇÃO  Camilo de Lelis Teixeira de Andrade1; Bruno Leite Teixeira Perroni2; Paulo Emílio Pereira de Albuquerque1; Gabriel Roberto Oliveira1; Fernando Falco Pruski3; Flávio Aparecido Gonçalves31Embrapa Milho e Sorgo,  Sete Lagoas, MG,  [email protected] de Engenharia, Universidade Federal de Lavras, Lavras, MG3Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, Viçosa, MG  1 RESUMO Em comportas que operam como orifícios retangulares, a variação do nível da água no canal afeta a vazão do orifício, o que provoca erros na estimativa do volume de água derivada. Objetivou-se com esse projeto desenvolver e avaliar dispositivos que possibilitem melhor controle da derivação de água para os lotes. A comporta tipo Módulo de Máscara XX1, comumente utilizada no perímetro,foi aferida no local e suas características hidráulicas comparadas com os dados do fabricante. Três tipos de dispositivos de derivação de água foram desenvolvidos e avaliados, todos baseados na manutenção do nível da água sobre um orifício. No protótipo 1, procura-se manter o nível da água fechando ou abrindo uma portinhola que atua contra o fluxo de entrada de água. No protótipo 2, uma portinhola atua no sentido do fluxo de água como em um carneiro hidráulico. No protótipo 3 o nível da água é mantido constante fechando ou abrindo a saída de um mangote flexível. O módulo de 10 Ls-1 da comporta XX1 apresentou erros de até 20% da vazão nominal quando submetida a níveis de água no canal acima ou abaixo do valor recomendado, conforme reportado no catálogo do fabricante. Dos três protótipos desenvolvidos, o que proporcionou melhor resultado foi de número 3. Testes com o protótipo 3 indicaram que variações máximas de 3,4% na vazão derivada foram observadas para oscilações de30 cm no nível do canal. UNITERMOS: comporta, orifício, medição de água.  ANDRADE, C. L. T.; PERRONI, B. L. T.; ALBUQUERQUE, P. E. P.; PRUSKI, F. F.; OLIVEIRA, G. R. DEVELOPMENT AND EVALUATION OF IRRIGATION CANAL DEVICES FOR WATER TURNOUT CONTROL  2 ABSTRACT In water turnouts that operate by gravity as a rectangular gate, variation on the canal water level affects the estimated discharge to plots. This work objective was to develop and evaluate devices for a better water turnout to plots. An existing commercial gate model XX1, was evaluated in situ and its hydraulic characteristics compared to manufacturer´s data. Three types of water turnout devices were developed and evaluated, all of them based on the principle of maintaining a constant water level over an orifice. In prototype 1, water level is maintained by opening or closing a gate against the inlet water flow. In prototype 2, the gate is positioned in the flow direction, like in a water hammer. In prototype 3, water level is kept by opening or closing a flat hose outlet. The 10 Ls-1 module of a XX1 gate causes errors of up to 20% of the nominal discharge when operated under water levels above or below the recommended value by the manufacturer. Considering three developed prototypes, a better water turnout control was obtained with prototype 3. Tests with prototype 3 indicated that a maximum of 3.4% of the derived discharged was observed for fluctuations of up to30 cm on the canal level.  KEYWORDS: gate, orifice, water measurement.


CORROSION ◽  
1957 ◽  
Vol 13 (4) ◽  
pp. 75-77

Abstract Descriptions are given of various systems using asphalt, physical characteristics of primers and coatings, means of testing characteristics, recommended application criteria and handling of material after coating. An appendix gives a test for settlement of mineral filler in tilled asphalt pipe line enamels. 5.4.5


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