Bolts are the most commonly used parts in engineering structures. Accurate monitoring of the working condition of bolts is essential to ensure structural safety, but there has been a lack of effective technical approaches in the market.In order to solve the long-standing engineering challenge of monitoring bolt loads and looseness in real time, we offer wired instrumentation bolts with sensitive elements (strain sensors) integrated into the screw head and remote measurement conditioners with modulated analog output signals.For the EI range, the measurement conditioner (memory and measurement) outputs an analog signal.The third series is called TM-FAST-W，and uses wireless technology. Our latest prototype uses point-to-point communication via NFC (Near Field Communication).

 I. Products

TM-FAST-TH-EM

  TM-FAST-TH-EM Instrumentation Screw with Strain Sensor and Remote Measurement Conditioner, TM-FAST offers in its TH series a wired instrumentation screw with the sensitive element (strain sensor) integrated in the screw head and a remote measurement conditioner with a modulated analog signal output.This version, called EM, stays wired and does not create separation between the screw heads. The strain transducer uses the sensitivity of a strain gauge to measure the strength of the tensile effect on the screw. The pressure gauge is fixed inside the screw head, minimizing the loss of mechanical strength of the screw.

TM-FAST-TH-MC

  TM-FAST-TH-MC Instrumentation Screw with Strain Sensor, Remote Measurement Conditioner and Magnetic Connector TM-FAST offers in its TH series a wired instrumentation screw with the sensitive element (strain sensor) integrated in the screw head and a remote measurement conditioner with a modular analog signal output.This version, called MC, contains a magnetic connector on the screw head. The strain transducer uses the sensitivity of a strain gauge to measure the strength of the tensile effect on the screw. The pressure gauge is fixed inside the screw head, minimizing the loss of mechanical strength of the screw.

TM-FAST-TH-CO

  TM-FAST-TH-CO Instrumentation Screw with Strain Sensor and Remote Measurement Conditioner, TM-FAST offers in its TH series a wired instrumentation screw with the sensitive element (strain sensor) integrated in the screw head and a remote measurement conditioner with a modular analog output.This version, named CO, contains an adhesive connector between the screw head and the regulator. The strain sensor can be used to monitor strain changes in various structures over long periods of time. The strain gauge sensor uses the sensitivity of the strain gauge to measure the strength of the tensile effect on the screw. The pressure gauge is fixed inside the screw head, minimizing the loss of mechanical strength of the screw.

TM-FAST-EI-MC

    TM-FAST-EI-MC Instrumentation Screw with Strain Sensor, Integrated Measurement Conditioner and Magnetic Connector TM-FAST offers in its EI series a wired instrumentation screw with a sensitive element (strain sensor) integrated into the screw head and a measurement conditioner (memory and measurement) with analog signal output.This version, called MC, incorporates a magnetic connector on the screw head. TM-FAST-EI-MC works in conjunction with TM-FAST-EIAST, which provides an additional layer that allows the analog values to be filtered and converted to provide a serial link via USB.The strain gauge sensor uses the sensitivity of the strain gauge to measure the strength of the tensile effect on the screw. The pressure gauge is fixed in the screw head to minimize the loss of mechanical strength of the screw. Computational intelligence is embedded in the screw head with built-in memory.

TM-FAST-W

  TM-FAST-W self-powered instrument screw with strain sensor, integrated measurement regulator and NFC wireless technology TM-FAST offers in its W series a wireless instrument screw that integrates the sensitive element (strain sensor) into the screw head and the measurement regulator (memory and measurement).This version named W has an NFC chip integrated in the screw head in order to restore power to the reader during reading. The application developed for this purpose can read the digital values transmitted by the regulator and convert them into loads.

II. Working Principle

  Through the fiber optic grating sensor buried in the finished bolt, the load changes in the bolt working condition can be monitored in real time, and the collected data can be analyzed and processed by the background software, which can show the user the tensile force, shear force value, change curve in the bolt working condition, parameter preset for overload, alarm when the overload condition is reached, and also judge the bolt loosening. The system can provide APP remote information pushing function, which is convenient for users to monitor from a distance.

User monitoring interface presentation:

  The product has already started to be applied in the ship industry with remarkable effect, solving the problem that the state of bolts in key structural parts of ships cannot be monitored for a long time, thus reducing the safety incidents caused by excessive fracture and loosening of bolts due to excessive loads existing during the navigation of ships. The technology can provide solutions in many fields such as shipbuilding, construction safety, rail transportation, road and bridge, petrochemical facilities, wind power equipment, power grid safety, and automobile manufacturing.