The Model 3714 Portable Torque Calibrator is a self-contained standards lab designed to generate, control, measure, and display the rotational forces applied to torque measuring instruments. Users can calibrate a variety of general purpose torque measur- ing instruments, such as wrenches, screwdrivers, T-handle drivers, and torque watches in the clockwise and counter-clockwise directions. Versions are available with a 250 ft-lbs maximum range and a 500 ft-lbs maximum range. Using the included adapters, the Model 3714 PortableTorque Calibrator can accommodate all direct reading dial and beam type, and click type micrometer torque measuring instruments. The system incorporates a unique precision torque loading system consisting of a hand wheel coupled to a torque measuring transducer via a double-reduction worm gear. The worm gear mechanism eliminates the potential for errors and inaccuracies introduced by variations in the load applied by the operator when conventional torque calibrators are used.
By precisely controlling the load applied to the unit under test, the Model 3714 Portable Torque Calibrator offers measurement accuracy of ±0.5% of reading from 10% to 100% of the transducer measurement range and repeatability of ±0.15% of reading or ±0.2 in-oz, whichever is greater. An electromagnetic brake prevents the hand wheel from turning when the calibration point is exceeded, protecting the unit under test from damage due to over-torquing. A torque reaction arm and restraining post prevent the handle of the unit under test from moving during calibration, while a removable Lexan shield protects the operator in the event of tool breakage.
Three operating modes are available. The TRACK mode displays instantaneous torque readings throughout the measurement range in real time in the upscale and downscale directions. The MAXIMUM mode displays ascending torque values in real time until the applied torque is backed off, at which the maximum torque is displayed until it is cleared. The FIRST PEAK mode is used for testing click type micrometer torque measuring instruments. In the FIRST PEAK mode, ascending torque values are displayed in real time until the click indicator releases. The first peak torque reading, representing the point at which the click indicator releases, will then be displayed until it is cleared. All components in the Model 3714 250 ft-lbs and 500 ft-lbs torque calibrator kits are conveniently stored in rugged and weatherproof transit cases. Everything required for operation, maintenance, and calibration packs quickly and neatly into a small amount of space, making the Model 3714 an ideal field standards lab for remote locations and other places where testing and maintaining torque measuring tools may be difficult.
Software-Driven Controls for Ease of Use
All aspects of the measurement process using the Model 3714 Portable Torque Calibrator are automated using custom-designed King Nutronics controller software running on a PC-compatible computer.
Measurement and test setup information is summarized in a comprehensive workscreen, which is also used to access controls and functions used during testing.
A status display in the workscreen prompts the operator through each step of the measurement process.
A numerical display in the workscreen displays instantaneous torque measurement readings, the directon of rotation, and the units in use. Available units are shown in a menu.
A Sequence grid in the workscreen displays the nominal test points and the test progress. The operator can repeat test points as necessary.
Test results, including the PASS/ FAIL status, the measured error, and the error tolerance, are displayed in tabular format in a second grid in the workscreen.
Test results can be viewed and print- ed within the application, or exported in tab-delimited format for statistical processing using MS Excel or other spreadsheet programs.
Test profiles for specific tools and measurement ranges can be created and saved by the operator for later use. Saved profiles can be quickly re-loaded when needed, reducing the time required for tool setup.
The control console software is connected to the calibrator stand using a standard RJ-45 terminated Ethernet cable. A small metal enclosure on the calibrator stand houses the system electronics, such as the digital-to-analog converter for the torque transducers and the brake trigger.
A Tools menu in the software configures the communication settings and accesses password-protected functions.
A password-protected Calibration tab is used to access controls needed during transducer calibration and standardization. Software prompts guide the operator through the calibration process, reducing errors and uncertainties.
Calibrates Direct Reading and Micrometer-Type Torque Wrenches
TRACK mode for beam-type wrenches
FIRST PEAK mode for click- type wrenches
Reaction Bar Extender for Small Torque Wrenches
Calibrates in-lbs, in-oz, and kg-cm torque measuring tools
Vertical Test Fixture and Specialized Adapters
Calibrates screwdrivers, T- handles, and torque watches