Method and apparatus for monitoring pipeline expansion joint conditions

The combination of an apparatus for monitoring pipeline expansion joint conditions, and a pressure-balanced expansion joint, having a fluid flow path therethrough, the combination comprising:

• a pressure-balanced expansion joint connecting first and second pipe ends;
• at least one sensor operably configured to sense and respond to environmental conditions existing within pipeline fluid flow through the pressure-balanced expansion joint;
• the at least one sensor being further operably configured to generate a first signal corresponding to a particular value of at least one quantifiable characteristic of the environment existing within the pipeline fluid flow through the pressure-balanced expansion joint;
• a control apparatus, operably connected to the at least one sensor and configured to receive said first signal,
• the control apparatus being further operably configured to compare the first signal received from the at least one sensor with numerical values stored in memory corresponding to various potential environmental conditions of the pipeline fluid flow through the pressure-balanced expansion joint and determine the environmental condition to which the received first signal corresponds,
• the control apparatus further being operably configured, upon determination of the environmental condition to which the first signal corresponds, to generate a second signal;
• a source of compressible medium;
• a flow control valve, operably connected to at least the source of compressible medium and a variable enclosed volume defined by at least first and second balancing bellows of the pressure-balanced expansion joint,
• the flow control valve being further operably configured to have at least two operating positions, a first operating position preventing flow through the flow control valve, and a second operating position permitting flow between the source of compressible medium and the variable enclosed volume defined by the at least first and second balancing bellows of the pressure-balanced expansion joint;
• the second signal being configured to direct the flow control valve to one of the at least two operating positions, and depending upon the environmental condition to which the first signal corresponds, to, in turn, add compressible medium, remove compressible medium and/or maintain the mass of compressible medium within the defined variable enclosed volume.