Low cost transducer bonding tooling and techniques are provided which can be used to duplicate the quality of factory manufactured load indicating members, and to allow transducers to be attached to fasteners irrespective of their orientation. The bonding tooling and techniques can also be used to bond other small objects requiring precise placement and reliable bonding such as, for example, the bonding of identification labels to manufactured components or structures.

The present disclosure provides an apparatus and a method for predicting attenuation of a pre-tightening force of a bolt, which relate to the field of prediction on the pre-tightening force of a bolt. The apparatus for predicting attenuation of a pre-tightening force of a bolt includes a pre-tightening force coefficient measuring device, including a clamping assembly, a pre-tightening force detecting assembly, a tightening assembly and a time length measuring assembly. The clamping assembly is configured to fix a bolt to be detected; the pre-tightening force detecting assembly is configured to measure the pre-tightening force to the bolt; the tightening assembly is configured to apply the pre-tightening force to the bolt; the time length measuring assembly is configured to measure a time length of each sampling in the process of tightening the bolt.

A method and apparatus for measuring a preload of a fastener. The method, which may be practiced at least in part by the apparatus, includes establishing an initial value associated with an absence of the preload of the fastener and providing an adapter and a transducer rotatably coupled to the adapter. The transducer may be positioned in contact with the fastener. The transducer is caused to direct an incident ultrasonic wave to the fastener and to receive a reflected ultrasonic wave from the fastener. Data associated with the incident ultrasonic wave and the reflected sonic wave is used to generate a modified value associated with the preload of the fastener, and the preload of the fastener is calculated based on a difference between the initial value and the modified value.

A sensor unit for inducing and indicating ultra sonic sound waves in at least one threaded fastener by physical contact with an end surface thereof, wherein the sensor unit includes: a support casing, a sensor element with forward contact surface for engaging the fastener end surface and movable relative to the support casing between rest and active positions, and a bias spring between the support casing and the sensor element to urge the sensor element into the rest position as the sensor element is out of contact with the fastener end surface and to bias the contact surface of the sensor element into physical contact with the fastener end surface in the active position. The support casing includes a positioning socket, engaged by the sensor element in the rest position, having a non-cylindrical and non-circular cross sectional inner shape and congruent with an outer shape of the sensor element.

A method and apparatus for measuring a preload of a fastener. The method, which may be practiced at least in part by the apparatus, includes establishing an initial value associated with an absence of the preload of the fastener and providing an adapter and a transducer rotatably coupled to the adapter. The transducer may be positioned in contact with the fastener. The transducer is caused to direct an incident ultrasonic wave to the fastener and to receive a reflected ultrasonic wave from the fastener. Data associated with the incident ultrasonic wave and the reflected sonic wave is used to generate a modified value associated with the preload of the fastener, and the preload of the fastener is calculated based on a difference between the initial value and the modified value.

An wheel fastening inspection method includes: directly or indirectly applying vibration to a turbine shaft to be inserted to a bearing housing, the turbine shaft being provided with wheels at both ends protruding from the bearing housing, at least one of the wheels being fastened by a fastening member, and a rotary member being fastened by a fastening force generated by the fastening member to the turbine shaft to be integrally rotated with the wheel; measuring the vibration of the turbine shaft; and determining whether or not a vibration frequency at which a peak of the measured vibration of the turbine shaft is given is included in a setting range previously set.

A looseness detection sensor for detecting looseness of a bolt for fixing a component, including: a resonance unit arranged adjacent to a head portion of the bolt and made of an insulating material confining a high-frequency signal input externally; and a conductive member in conduction with the component across the resonance unit, wherein the conductive member is a cap put on the head portion of the bolt and includes a protrusion contacting a surface of the component.

A fastener strain measurement system employs a probe incorporating a laser emitter to provide a laser beam and an acoustic detection device. A system controller is configured to detect an acoustic wave resulting from the ablation created by the laser beam and calculate fastener strain based on the detected acoustic wave.

The invention relates to a method of measuring elongation of a fastener by means of minimum peak side lobe (MPS) coded ultrasonic signals, and a power tool configured to performing the method. MPS coded signals with different base frequencies are transmitted into the fastener and a corresponding set of reflected signals are received from the fastener. Each reflected signal is cross-correlated with the corresponding transmitted signal, and a quality attribute of each transmitted signal is determined from the cross-correlated signals. Based on the quality attributes at least one parameter of an ultrasonic measurement signal is determined and the measurement is performed by transmitting the ultrasonic measurement signal into the fastener, and receiving a reflected ultrasonic measurement signal.

Low cost transducer bonding tooling and techniques are provided which can be used to duplicate the quality of factory manufactured load indicating members, and to allow transducers to be attached to fasteners irrespective of their orientation. The bonding tooling and techniques can also be used to bond other small objects requiring precise placement and reliable bonding such as, for example, the bonding of identification labels to manufactured components or structures.