A method that consists of the following steps: depressuring and isolating the annular space; recording a first pressure and temperature prevailing in the annular space; injecting a given amount of a measuring gas into the annular space and isolating the annular space, the annular space remaining under negative pressure after the injection and isolation; measuring the given amount of measuring gas; recording a second pressure in the annular space after the isolation of the annular space; and determining the free volume of the annular space on the basis of the first pressure, the second pressure, the temperature, and the measurement of the given amount of measuring gas.

An integrity monitoring system for a lined pipeline is provided for monitoring the integrity of a polymer liner in a host pipe. Methods and apparatus are described by which a lined pipeline is provided with such an integrity monitoring system sensor cable is able to bridge a joint between sections of lined pipe, for example by routing the sensor cable across the joint via a channel in an electrofusion fitting or by connecting successive lengths of sensor cable via pass-throughs in an electrofusion fitting. Advantageously, the sensor cable is disposed within a continuous annulus between linings and host pipes, and the continuous annulus is maintained across pipe joints using electrofusion fittings.

In accordance with at least one aspect of this disclosure, a fluid system of an aircraft includes a primary fluid conduit that conveys a primary fluid, and a leak detection system disposed around at least a portion of the primary fluid conduit and forming one or more detection volumes. The leak detection system determines whether there is a primary fluid leak into the one or more detection volumes by sensing a pressure change in the one or more detection volumes.

In accordance with at least one aspect of this disclosure, a fluid system of an aircraft includes a primary fluid conduit that conveys a primary fluid, and a leak detection system disposed around at least a portion of the primary fluid conduit and forming one or more detection volumes. The leak detection system determines whether there is a primary fluid leak into the one or more detection volumes by sensing a pressure change in the one or more detection volumes.

An oil pipe assembly for a gas turbine engine. The oil pipe assembly includes a first pipe that defines a first fluid passage between an oil supply and a bearing chamber, and a second pipe that houses the first pipe and defines a second fluid passage between the first pipe and the second pipe that is supplied with cooling air. The oil pipe assembly also includes a restrictor that extends from the second pipe and restricts the passage of fluid from the second fluid passage before it flows into a breather. Pressure and temperature sensors) are located adjacent the restrictor to detect and measure changes in air pressure and air temperature adjacent the restrictor from which a controller identifies whether a leak has occurred in the first pipe or the second pipe. A method for detecting a leak in the oil pipe assembly, and a gas turbine are also described.

A coupling for connecting vacuum-insulated piping is disclosed. The coupling facilitates the detection of unwanted fluid ingress into the low pressure insulating outer portion of the vacuum-insulated piping and the detection of a leak from the central portion of the vacuum-insulated piping that is used to carry cold fluids. This is achieved by providing a first leak path from the central portion of the vacuum-insulated piping to a sensor outlet and a second leak path from the outer portion of the vacuum-insulated piping to the sensor outlet. One sensor may be used to detect unwanted fluid ingress into the low pressure insulating outer portion and also detect a leak from the central portion of the vacuum-insulated piping.

A pipeline including at least first and second portions, each comprising outer and inner pipes, at least one coupling system connecting the first and second portions and including at least a downstream flange ring connected to at least one of the outer and inner pipes of the first portion, at least an upstream flange ring connected to at least one of the outer and inner pipes of the second portion, connecting elements connecting the upstream and downstream flange rings, first and second annular seals interposed between the upstream and downstream flange rings and configured to delimit, with the upstream and downstream flange rings, a buffer space containing an atmosphere, the pipeline comprising at least one leak detection system configured to determine at least one characteristic of the atmosphere of the buffer space.

A fire sprinkler system according to one aspect of the present disclosure includes a pipe having a first pipe portion and a second pipe portion. The first pipe portion includes a wall having a first wall thickness, and the second pipe portion includes a wall having a second wall thickness that is greater than the first wall thickness. The fire sprinkler system further includes structure coupled to the pipe and defining a sealed chamber between the structure and at least the first pipe portion, and a sensor for sensing a pressure in the sealed chamber. Example corrosion monitoring devices and methods for monitoring corrosion in pipe systems, including fire sprinkler systems, are also disclosed.

A method that consists of the following steps: depressuring and isolating the annular space; recording a first pressure and temperature prevailing in the annular space; injecting a given amount of a measuring gas into the annular space and isolating the annular space, the annular space remaining under negative pressure after the injection and isolation; measuring the given amount of measuring gas; recording a second pressure in the annular space after the isolation of the annular space; and determining the free volume of the annular space on the basis of the first pressure, the second pressure, the temperature, and the measurement of the given amount of measuring gas.

Described herein is an autonomous fluid spill containment device for a pipeline which has a carrier conduit for transporting a fluid and a containment conduit located around the carrier conduit to define an interstitial space for receiving fluid spilled from the carrier conduit. The device includes a spilled fluid barrier for stopping spilled fluid flow. The fluid barrier is located in the interstitial space and extending between the carrier conduit and the containment conduit. A cable sensor is associated with the containment conduit for detecting spilled fluid flowing in the containment conduit.