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  1. Bolt Tension Monitors

Dakota Ultrasonics Mini-Max Bolt Tension Monitor

Ultrasonically measures the actual elongation produced by tightening a threaded fastener.

Dakota Ultrasonics Mini-Max Bolt Tension Monitor
Dakota Ultrasonics Mini-Max Bolt Tension Monitor
Retired products cannot be ordered
The Dakota NDT BT1-DL Handheld Bolt Tension Monitor is the recommended replacement

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Part Number
  • Z-156-0006
Manufactured
  • By Dakota NDT
Includes
  • FREE Ground Shipping
  • FREE Lifetime Tech Support
Product Manual Product Specs
Questions?
Call 1-800-884-4967 or email sales@instrumart.com. Open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET.
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Overview

Features

  • Range: 1/2in up to 50ft (15.24m)
  • Resolution: ±0.00001 inch (0.0001 mm)
  • Auto calibration for system zero
  • Built in load calibration toolkit
  • Large 110 dB gain range
  • 4GB internal SD memory
  • Display options: A-scan, large digits, alarm limits bar
  • Hi/Lo alarm limit used for for tolerances

What's in the Box

  • Couplant
  • 10ft Lemo to Microdot cable
  • AA batteries
  • USB Cable
  • Manual
  • Carrying case

Description

The Dakota Ultrasonics Mini-Max bolt tension monitor can ultrasonically measure the actual elongation produced by tightening a threaded fastener. This bolt tension monitor allows you to effectively monitor your bolts during periodic shutdowns over the service life of the fastener and visually compare the unloaded and loaded waveforms. The Mini-Max can measure bolts 1/2″ up to 50 ft (15.24m). The square wave pulser is selectable in 100, 150 and 200 volts. It features a large 110 dB gain range and a resolution of ±0.00001 inch (0.0001 mm).

Documents

Spec Sheets

  • Dakota Ultrasonics Mini-Max Bolt Tension Monitor Datasheet PDF (313 KB)

Manuals

  • Dakota Ultrasonics Mini-Max Bolt Tension Monitor Manual PDF (821 KB)

Accessories

Required Components

These additional components are required for the operation of your product. We strongly advise you to purchase these components unless you already own them or own a suitable alternative.

Dakota NDT Single Element Contact Transducers
Dakota NDT Single Element Contact Transducers

Magnetic and non-magnetic single element contact transducers for BT1-DL bolt tension monitors.

Starting at $375.00
Dakota NDT A-156-8001 Temperature Sensor
Dakota NDT A-156-8001 Temperature Sensor

Temperature sensor for the Mini-Max Bolt Tension Monitor.

$570.00

Calibration

Dakota NDT Calibration Bars
Dakota NDT Calibration Bars

Steel calibration bars for ultrasonic bolting equipment.

Starting at $370.00
Dakota NDT X-000-0008 Glass Calibration Blocks
Dakota NDT X-000-0008 Glass Calibration Blocks

Glass calibration blocks (1in, 2in and 3in) for ultrasonic bolting equipment.

Call for pricing

Accessories

Please consider these optional accessories.

Dakota NDT Couplant
Dakota NDT Couplant

Acoustic couplant to apply to the sensor face to ensure a complete acoustic pathway between the sensor and material being measured.

Some Models in Stock
Starting at $20.00
Dakota NDT Single LEMO 00 to Pin Fixture Cable
Dakota NDT Single LEMO 00 to Pin Fixture Cable

4 foot cable for Dakota NDT BT1-DL and BT2-DL tension monitors with selectable connection types .

Starting at $225.00
Dakota NDT Single LEMO 00 to Microdot Cable
Dakota NDT Single LEMO 00 to Microdot Cable

Cable for Dakota Ultrasonics FX70, FX80, PMX2-DL, CMX, BT1-DL, and BT2-DL series.

Starting at $80.00
Dakota NDT Instrument Case
Dakota NDT Instrument Case

Nylon case with clear plastic front, snap closure, and neck strap.

$90.00

Applications

This product can be used in the following applications:

  • Automotive
  • Building Inspection / Restoration
  • Oil, Gas and Petrochemical
  • Power Generation
  • Preventative Maintenance

Here's how some of our customers use this product...

Extreme Precision Bolt Lengthening

The Background: Our customer is an aerospace company that needs to monitor the elongation of a new type of bolt under stress as part of their testing protocol.

The Problem: The bolt is a proprietary alloy designed for optimal strength to weight ratio. The engineers need to test bolt elongation down to less than one thousandth of an inch (~0.00099-inches).

The Solution: The Dakota Mini-Max Bolt Tension Monitor will meet this resolution requirement. Given the length of this bolt, about 5 inches, this will require the customer to eliminate all possible error effects due to transducer placement and installation. For these extreme applications, Dakota has developed glue-on transducers that remain firm once the glue sets. This removes the human element of holding the transducer still and with constant pressure. The glue can easily be softened with a solvent so the transducer and, more importantly, the bolt can be put back into service.

Monitoring Bolt Elongation in Critical Assets

The Background: Our customer is a power plant that needs to monitor the large bolts that hold together the steam turbines for signs of stress

The Problem: The steam turbines, perhaps the most critical part of a power plant, utilize a number 2-inch bolts that hold the turbine together. As the turbine spins and generates electricity, these bolts are subject to a huge amount of force. Failure of a bolt would be catastrophic so our customer wants absolute certainty that the bolts are structurally sound.

The Solution: This is a typical application for the Dakota Ultrasonics Mini-Max Bolt Tension Monitor. The MiniMax measures the actual elongation produced by tightening a threaded fastener and includes temperature compensation probe which creates a constant temperature reference point for all measurements. With all variables removed, the change in bolt length can be accurately interpreted by the customer.

The MiniMax is available with both magnetic and non-magnetic style probes to help reduce human error where possible. The magnetic probes hold steady in place while the measurement is made, further reducing error on ferromagnetic based bolts.

A complete kit would typically consist of a combination of magnetic and non-magnetic probes, temperature compensation gauge and calibration bars. With a complete kit, the customer can accurately monitor their bolts and determine when they need to be replaced.

Need Help? Call a Waygate - Borescope (Flow) engineer at 1-800-884-4967

We're open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET

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Dakota Ultrasonics Mini-Max Bolt Tension Monitor
Dakota Ultrasonics Mini-Max Bolt Tension Monitor
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