Abstract: A leakage detection arrangement has a membrane sheet wrapping a pressure boundary joint. First and second adjustable bands tighten around the membrane sheet forming a gas enclosure around the joint. A gas flow arrangement enables gas flow into or out of the gas enclosure. Gas flow measuring arrangement signals indicate gas flow rate. An electronic control unit monitors the gas flow rate indicative signals and changes an output signal when the gas flow rate indicative signal varies beyond a predetermined amount. A leakage detection apparatus vacates or inflates the enclosure to a steady state pressure. Initial or baseline state can be recorded during steady state with pressure system depressurised. Pressure system can be pressurised and pressure and/or flow rate and/or other parameter(s) indicative of pressure or flow rate can be compared to the initial or baseline state. Any difference indicates leakage of the joint.

Abstract: A reaction torque limiting backup wrench arrangement (1) has at least one fastener engaging means e.g. spanner (6) or socket (170), for a pressure boundary bolted joint nut (5) of a respective fastener (3). The backup wrench arrangement provides a reaction torque up to a threshold above which rotation allowed by motion of the fastener engaging means is determined by a magnitude of the reaction torque and force deflection characteristic of a biasing arrangement acting directly or indirectly on the fastener engaging means. Tension in the flexible tension element e.g. chain (7) urges the spanner (6) onto the nut (5) of the fastener permitting the spanner to displace when torque transmitted through a bolt to the nut or bolt head within the spanner exceeds a threshold torque, enabling the nut or bolt head to rotate, helping prevent bolt over-tightening, and helping indicate the bolt seizing or galling.

Abstract: A bolt load measuring arrangement 31 has a bolt 4 with a reference pin 10 extending from the root 12 of a hole 11 in the bolt. Shoulder 23 of a bore 22 defines a strainable portion datum shoulder located within the strainable portion 7 of the bolt 4. Strain datum sleeve 32 can have a strain datum surface 16 at its outer end. The strain datum sleeve 32 has a hole 33 to allow it to pass around the reference pin 10 which extends to the end of the strain datum sleeve. The reference datum 15 is on the outer end of the reference pin 10 and the strain datum 16 is on the outer end of the strain datum sleeve 32. The outer end of the strain datum sleeve includes an alignment protrusion 34 over which the measuring tool 40 engages. Fit between the alignment protrusion and the tool 40 is essential to achieving the alignment accuracy for accurate datum relative position measurements and therefore accurate load measurement.

Abstract: A reaction torque limiting backup wrench arrangement (1) has at least one fastener engaging means e.g. spanner (6) or socket (170), for a pressure boundary bolted joint nut (5) of a respective fastener (3). The backup wrench arrangement provides a reaction torque up to a threshold above which rotation allowed by motion of the fastener engaging means is determined by a magnitude of the reaction torque and force deflection characteristic of a biasing arrangement acting directly or indirectly on the fastener engaging means. Tension in the flexible tension element e.g. chain (7) urges the spanner (6) onto the nut (5) of the fastener permitting the spanner to displace when torque transmitted through a bolt to the nut or bolt head within the spanner exceeds a threshold torque, enabling the nut or bolt head to rotate, helping prevent bolt over-tightening, and helping indicate the bolt seizing or galling.

Abstract: A member (10), for bearing a load, including a load receiving portion (12) at which the load is applicable to the member. A strainable portion (14) is connected to the load receiving portion to be strained by the load. A datum (16a) is defined and an elongate portion (18) defines another datum (18a). The datums are arranged such that relative displacement therebetween indicates an amount by which the strainable portion is strained. The strainable portion defines the datum.

Abstract: A bolt load measuring arrangement 31 has a bolt 4 with a reference pin 10 extending from the root 12 of a hole 11 in the bolt. Shoulder 23 of a bore 22 defines a strainable portion datum shoulder located within the strainable portion 7 of the bolt 4. Strain datum sleeve 32 can have a strain datum surface 16 at its outer end. The strain datum sleeve 32 has a hole 33 to allow it to pass around the reference pin 10 which extends to the end of the strain datum sleeve. The reference datum 15 is on the outer end of the reference pin 10 and the strain datum 16 is on the outer end of the strain datum sleeve 32. The outer end of the strain datum sleeve includes an alignment protrusion 34 over which the measuring tool 40 engages. Fit between the alignment protrusion and the tool 40 is essential to achieving the alignment accuracy for accurate datum relative position measurements and therefore accurate load measurement.

Abstract: A member (10), for bearing a load, including a load receiving portion (12) at which the load is applicable to the member. A strainable portion (14) is connected to the load receiving portion to be strained by the load. A datum (16a) is defined and an elongate portion (18) defines another datum (18a). The datums are arranged such that relative displacement therebetween indicates an amount by which the strainable portion is strained. The strainable portion defines the datum.