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Model MZ Base Unit

$ 4,250.00
The Model MZ Manual is available for download!

IMPORTANT NOTE:  This unit will not function independently.  Please review our adapter sets to find the specific diameter(s) you need or purchase one of our MZ Kits.


The Model MZ Bolt Tension Calibrator Allows You to Verify:

  • Fasteners meet minimum bolt tension specifications.

  • Impact wrenches are properly calibrated to achieve proper tension in the bolted joint.

  • Tension-control fasteners sheer off at the correct tension.

  • Direct Tension Indicating (DTI) washers are indicating at proper tension

  • Bolting crew understands how to achieve proper tension in all types of fasteners

  • You have the right installation tools and equipment.

If you have any questions or need more information request a free quote today.

Capacity: 126,000 lbs. Of Bolt Tension

The MZ-100 can be used with our adapter kits to test the following bolts sizes:

1/2" bolts
5/8" bolts
3/4" bolts
7/8" bolts
1" bolts
1-1/8" bolts
1-1/4" bolts
as well as metric equivalents M12, M14, M16, M18, M20, M22, M24, M27, M30.X


For Accurate Measurement of Bolt Tension In Short Structural Fasteners
Two developments in construction practice have created a demand for the Model MZ bolt tension calibrator: thinner sections of structural steel and the use of tension-control bolts. Designed to accept shorter grip length bolts, the Model MZ provides all the features and capabilities of our standard Model M and MS calibrators.

Whether calibrating power wrenches or testing fasteners, you need no special training, no additional equipment. Simply clamp the calibrator to a beam or column and insert your fastener. Tightening it gives a direct dial pressure reading equivalent to the tension created in the fastener—guaranteed accurate within 1% every time.


For Economical Quality Assurance
With a Skidmore-Wilhelm Model MZ, you can accurately simulate joint conditions, then transfer your tightening procedure to the joint itself. Result: consistent tightening to bolt tension specifications.

The Research Council on Structural Connections recommends that a tension measuring device such as the Model MZ be available at every job site.* Obsolete torque checking methods will not let you meet approved bolt tension specifications.


Avoid Costly Rework and Re-inspection.
How do you give the best evidence of properly installed fasteners? First demonstrate with the calibrator that your tightening procedures produce proper bolt tension. Then consistently apply these procedures to the job itself.

Skidmore-Wilhelm Bolt Tension Calibrators let you build the inspection into your selected bolt tightening procedure. Proof of correct bolt tightening is right on the Model MZ calibrator dial.

*Research Council On Structural Connections, "Specification for Structural Joints Using ASTM or A490 Bolts." * Research Council On Structural Connections, "Specification for Structural Joints Using ASTM A325 or A490 Bolts."