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Dakota BT Bolt Tension Monitor
Product Description
The Dakota BT Bolt Tension Monitor uses ultrasound to precisely measure fastener elongation, time (nanoseconds), load, stress & %strain.
When nuts and bolts are fastened together under load the action of tightening the nut increases the force applied to the bolt causing elongation.
By using ultrasonics, bolt tension monitors are not affected by temperature, friction or resistance factors affecting the accuracy of standard torque measurement techniques – giving the Dakota BT1-DL Bolt Tension Monitor accuracy within 0.0001mm.
Using the gauge’s USB interface together with the optional shut off accessory the gauge can be programmed to automatically stop the tightening process when the appropriate load has been applied.
Applications
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Wind Turbines….. | Automotive Frames | Bridge Structures.. |
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Theme Parks…. |
Technical Specifications
Part Number | Description | Certificate |
Z-156-0008 | Dakota BT1-DL Bolt Tension Monitor (MiniMax) | ♦ |
Operating Temperature | -10 to 60ºC | |
Power Supply | 3 x AA batteries and via USB | |
Battery Life | Alkaline 35 hrs, Nicad 10 hrs, NI-MH 35 hrs | |
Gauge Weight | 383g – including batteries | |
Gauge Dimensions | 63.5 x 165 x 31.5mm |
● Certificate supplied as standard
Product Features
Model | BT1-DL |
Display Mode | |
Material thickness digits display | ♦ |
A-Scan | Rectified +/- (half wave view), or RF (full waveform view) |
Measurement Range | PE – 25.4 – 25,400mm |
Resolution | 0.001mm or 0.0001mm switchable |
Measurement Rate | |
Manual | 8 readings per second |
Velocity Calibration Range | 1250 – 13,995m/s |
Temperature Compensation | ♦ |
Limit Alarm Mode | ♦ |
Memory and Data Logging | 4GB internal memory Sequential and grid batching Bitmap graphic capture and capture viewer |
Calibration Options | Automatic, fixed, single and two-point |
Transducer Probe Type | Single element |
Transducer Frequency Range | 1 – 10MHz |
Display | 1/8” VGA greyscale display (240 x 160 pixels) Viewable area 62 x 45.7mm |
Units (Selectable) | mm, μs,°C |
LED Backlight | On / Off/ Auto |
Repeatability / Stability Indicator | ♦ |
Low Battery Indicator | ♦ |
Battery Save Mode | Auto |
Transducer Connector Type | Microdot, Lemo and BNC |
USB-C Interface | ♦ |
Temperature Sensor | 5 pin LEMO 1 |
Screen Refresh Rate | 30 Hz |
Timing | Precision TCXO timing with single shot 100 MHz 8 bit ultra-low power digitizer |
Pulser Type | Square Wave. Selectable 100, 150 and 200 volts. Selectable options Spike, Thin, and Wide. 80 to 400ns |
Damping | 50, 75, 100, 300, 600, & 1500ohms |
Frequency Band | Broadband 1.8 – 19 MHz (-3dB) filter |
Horizontal Linearity | +/- 0.4% FSW |
Vertical Linearity | +/- 1% FSH |
Amplifier Linearity | +/- 1 dB |
Amplitude Measurement | 0 to 100% FSH, with 1% resolution |
Delay | 25,400 mm at steel velocity |
Measurement Gate | One gate with audible and visual alarm. Amplitude 5-95%, 1% steps |
Setups | 64 custom user defined setups; factory setups can also be edited by the user |
Auto Set | Automates the detection, scope, and display setting process for each individual bolt |
Alarm Limits | Adjustable Hi/Low tolerances with visual LED’s and audible beeper |
Field Calibration | Vector or Regression correction curve for increased accuracy using Load & Stress |
Alarm Limits Bar | Hi & Lo alarm limits for displaying an acceptable tolerance range |
Detections | Zero Crossing |
Time | Nanoseconds |
Elongation | Change in length (mm) |
Load | Force load applied (pounds KIP, or megapascals MPa) |
Stress | Force for unit area stress applied (millimeters per millimeter) |
%Strain | Ratio of elongation to effective length |
Bolt Materials | Select types from a preset or custom list |
Glue-On | Available for short bolts with minimal/short elongations to eliminate transducer placement errors |
Data Sheet
Standards
Factory calibration traceable to NIST & MIL-STD-45662A
Accessories
1.8m RS232 ( DB-9 to lemo ) | ||
![]() | Part Number: | N-306-0010 |
USB to Serial Adapter | ||
![]() | Part Number: | N-402-0510 |
USB-C to USB TYPE A 1m data cable | ||
![]() | Part Number: | N-003-0330 |
Temperature Sensor with 1.8m cable | ||
![]() | Part Number: | A-156-8001 |
Packing List
Packing List | Z-156-0008 |
Unit | ♦ |
3x AA Batteries | ♦ |
Couplant | ♦ |
USB Type A to Type C Transfer Cable | ♦ |
Carrying Case | ♦ |
10’Lemo to Microdot Transducer | ♦ |
PC Untility Software (from website) | ♦ |
Operation Manual | ♦ |
Certificate | ♦ |
Part Numbers
Dakota BT1-DL Bolt Tension Monitor (MiniMax) | ||
![]() | Part Number: | Z-156-0008 |