US 4,450,711 A · Method of and device for remotely detecting leaks in a fluid-conveying pipe-line submerged within an ambient fluid and pipe-line provided with such a detection device

Abstract

A pipe-line for conveying a fluid submerged in an ambient fluid medium has an inner conveying tube surrounded by an outer tube radially spaced from the inner tube and defining a continuous annular space therebetween. A leak conductor communicating with a leak collector and surrounding the inner conveying tube conducts leaks of conveyed fluid to the leak collector. The leak collector has a reduced cross-section and is divided into adjacent sections isolated in a fluid-tight manner relative to each other and extending throughout the length of the tube. Each of the sections has at least a single valve automatically opened by predetermined pressure of the conveyed fluid leaks for providing communication with the annular space surrounding the inner tube. A leak detecting system in the annular space includes a sweeping device for sweeping the annular space with an auxiliary fluid and an analyzing device for analyzing the composition of the auxiliary fluid at one accessible end of the pipe-line and at spaced locations along the pipe-line. A warning device connected to the analyzing device is operable when the analyzing device indicates a predetermined condition.

Claims9

Dependent claims

A method for detection and location of fluid leaks in a pipe-line in an ambient fluid and having a tube conveying a fluid, said tube having a wall, said method comprising the steps of

surrounding the tube with a confined layer of sweeping auxiliary fluid interposed between the tube and the ambient fluid, said auxiliary fluid being a mixture of gases at least the main component of which is an inert gas at a pressure lower than the respective pressures of the conveyed fluid and the ambient fluid and being constantly kept flowing throughout the length of the pipe-line;
guiding any leak of conveyed fluid generally in a circumferential direction along the wall of said tube to accumulate said fluid into an accumulation volume divided into adjacent drain sections extending along said tube and isolated in sealing relationship from each other;
transferring the accumulated fluid to the auxiliary fluid when the pressure of the accumulated fluid within a drain section reaches a predetermined value;
sensing the presence of said conveyed fluid within said auxiliary fluid by continuous monitoring of the composition of said auxiliary fluid at one accessible end of said pipe-line and at spaced locations along said pipe-line;
and
emitting a signal indicative of the presence of said conveyed pipe in said auxiliary fluid as a result of said sensing.

3 more elements

A pipe-line for conveying a fluid submerged in an ambient fluid medium, said pipe-line comprising

an inner conveying tube surrounded by an outer tube radially spaced from said inner tube and defining a continuous annular space therebetween;
leak collecting means;
leak conducting means communicating with said leak collecting means and surrounding said inner conveying tube for conducting leaks of conveyed fluid to said leak collecting means, said leak collecting means having a reduced cross-section and being divided into adjacent sections isolated in a fluid-tight manner relative to each other and extending throughout the length of said tube, each of said sections having at least a single valve means automatically opened by predetermined pressure of the conveyed fluid leaks for providing communication with said annular space surrounding said inner tube;
leak detecting means in said annular space including sweeping means for sweeping said annular space with an auxiliary fluid and analysing means for analysing the composition of the auxiliary fluid at one accessible end of said pipe-line and at spaced locations along said pipe-line;
and
warning means connected to said analysing means and operable when said analysing means indicates a predetermined condition.

3 more elements

Dependencies are inferred from the claim text.

Method of and device for remotely detecting leaks in a fluid-conveying pipe-line submerged within an ambient fluid and pipe-line provided with such a detection device

Life of this patent

Method of and device for remotely detecting leaks in a fluid-conveying pipe-line submerged within an ambient fluid and pipe-line provided with such a detection device

Life of this patent

Abstract

Claims9