Dakota MultiMax – 4 Channel Bolt Tension Monitor

Overview

The Dakota MultiMax is a 4-channel ultrasonic bolt tension monitor built for continuous, simultaneous preload monitoring across multiple fasteners, using permanently installed glue-on transducers rather than a single handheld probe. It is used by asset-integrity teams and critical-machinery operators across Oman and the GCC who need ongoing, unattended tracking of bolt load on high-consequence joints rather than periodic spot checks.

Unlike the handheld BT1-DL or benchtop BT2-DL, which are used for on-demand spot measurements, the MultiMax is designed for permanent or semi-permanent installation, with each transducer bonded directly to its bolt so it can be monitored remotely and repeatedly without the placement variability of a handheld probe.

Operating Principle

The MultiMax uses the same pulse-echo ultrasonic elongation method as Dakota’s other bolt tension monitors, with zero-crossing detection for precise time-of-flight measurement, but multiplexes four channels through a single instrument, sequentially interrogating up to four glue-on transducers. Multiple MultiMax modules can be stacked together to expand the total number of monitored bolts on a single machine or structure, and the instrument includes automatic temperature compensation to correct for thermal expansion effects on the elongation reading.

Engineering Design of the Dakota MultiMax

The MultiMax measures fasteners from 1 inch to 50 feet (25.4 mm to 15.2 m), depending on material type and consistency, at a resolution of ±0.00001 in (0.0001 mm). Glue-on single-element transducers are available from 1 to 10 MHz across diameters from 1/8 to 1 inch, bonded permanently in place to eliminate the placement and movement errors possible with a handheld probe. Readings and RF waveforms are shown on an A-scan display with a large digital numeric readout, and data is archived automatically or manually to 4 GB of internal SD storage in both proprietary (.sm2) and CSV formats for later analysis.

Key Features

• 4-channel multiplexed monitoring, stackable for more channels
• Permanent glue-on transducers eliminate placement/movement error
• Bolt length range 1 in-50 ft (25.4 mm-15.2 m)
• Resolution ±0.00001 in (0.0001 mm)
• Automatic temperature compensation
• 4 GB internal memory, .sm2/CSV data export
• A-scan RF waveform display with large digital readout

Industrial Applications

Across Muscat, Sohar, and Salalah, the MultiMax is used for continuous preload monitoring on critical unspared machinery joints, flange connections, and structural bolting in power generation, oil and gas, and heavy-industrial facilities, where an undetected loss of bolt tension could lead to a safety or reliability incident. Its permanent transducer installation suits it to long-term condition-based monitoring programs rather than one-time inspection surveys.

The instrument is also specified for wind-turbine tower and foundation bolting and other structures where repeated re-inspection of the same bolts over time is required, since the bonded transducers guarantee measurement repeatability at the exact same point on each fastener.

Technical Specifications

Request a Quote for Dakota MultiMax – 4 Channel Bolt Tension Monitor

Seven Star LLC supplies the Dakota MultiMax 4-channel bolt tension monitor as an authorized channel partner to asset-integrity and industrial facilities across Oman and the GCC. Contact our engineering team for a formal quotation and guidance on permanent bolt-monitoring installations for your critical joints.