The bolt fastening axial, pre-tightening force, axial stress can directly be measured in real time through ultrasonic. The value of time difference which between the intelligent bolt system launch and receive ultrasonic pulse signal being calculated is called acoustic time difference.
The bolt axial force ultrasonic tester is widely applied in assembly testing domains such as automobile, aviation, aerospace, railway, wind power and nuclear energy. It has become a necessary testing instrument for bolt fastening system test and bolt assembly technology, providing strong guarantee for the R&D and design of bolt products as well as real-time testing and monitoring for the change of axial force.

Scope of Application
•Calibration of the assembly process;
•Field measurement of clamp force in important position;
•Real-time monitoring of several bolt clamp forces;
•In batch assembly, 100% of bolt tightening monitoring;
- Test range: M6-∞
- Measuring length: ≥3D, ≤1500mm
-Working temperature:-10°~60°
- Frequency range of transducer: 1-10MHz
- Type of transducer: magnetic/non-magnetic
- Stress range: 0-1100MPa
-Measurement unit: time-ns, elongation-mm/mm, load-KIP/KN, stress-KS/MPa, strain-%
-Length display resolution:0.0001mm

Requirements for testing bolt:
Both ends of the bolt must have reflective surface, at least the flat parallel plane is required.There is no problem with the processing of bolt headThe end of the bolt must be polished for a flat and smooth surface.