Electromagnetic Acoustic Transducer (EMAT) 

  Double-wave Bolt Stress Gauge (Model: ST100)

ST100 bolt stress gauge adopts EMAT dual-wave technology to measure the in-situ axial force of bolt in service without knowing the original length of each bolt. There is no need to smear couplant on the bolt, nor to polish the bolt surface. Measurements can be also taken for some bolts with protruding text on the bolt head, studs with thin diameter, bolts with inner hexagonal hole and bolts with concave surface. The stress gauge is widely used in the area of the check and acceptance of pre-tightening force of installed bolts during large-scale equipment manufacturing and assembling, treatment of bolt faults of large-scale equipment in service, independent verification of bolt installation technology and bolt axial force line-cruising technology of large-scale equipment in service.

＜＜＜Products

＜＜＜Product Description

• Global first EMAT double-wave bolt axial stress gauge (patent No. ZL201810893704.4);
• Technology that truly works for engineering application because it is capable of sensing bolt axial stress in situ without couplant or sample surface polishing;
• Portable design with replaceable lithium battery power supply; High brightness display with 5" screen; Special-designed  key position for one-handed operation;
• The device is iterative optimized for the field operation purpose with automatic wave selection, automatic result generation, one-key saving and delivering results within a few seconds;
• Integrated and concise design for easy access to narrow places such as fan wheel hub absence of traditional heavy equipment boxes or computer;
• The data in device can be imported into the computer and into the mobile phone through Bluetooth. The data can be uploaded to the company’s bolt cloud or the relevant configuration and data downloaded from the company’s bolt cloud;
• The powerful bolt cloud database supports equipment applications;

＜＜＜Technical Parameters

*Bolt condition as illustrated in GB/T 38952-2020. Another alternative more detailed condition: Roughness is less than 0.1mm for the two end faces. The included angle between one of the two end faces and the bolt axis is within π/2+±0.15R/L radian, where R is the radius of the bolt, L is the length of the bolt, and the thickness of the anti-corrosion paint is no more than 0.3mm.  

Note: the actual testing accuracy depends on the combination of repeated detection accuracy and the bolt calibration parameters input by the user.

＜＜＜Application Industries

• Wind power industry, such as axial force test of the wind turbine tower bolts and blade bolts;
• Bridge industry, such as axial force test of the connecting bolts on bridges;
• Power tower industry, such as axial force test of the connection bolts of communication base station; 
• Railway industry, such as axial force test of track bolts;
• Bolt design industry, such as high-strength bolts test, high-strength bolt installation technology, high-strength bolts R&D; 
• Automobile industry, such as for axial force test of engine bolts;