SmartBolts® Direct Tension Indicating Fasteners

Rhino Assembly Corporation and SmartBolts® have formed a partnership to offer DTI fastener systems technology to manufacturing facilities in North America.  DTI SmartBolts® from Stress Indicators, Inc.indicate whether a bolted joint is loose or tight with a clear, visible indicator that gradually darkens from bright red when loose to near black as the fastener is tightened. SmartBolts are simple. There are no wires, instruments or complex procedures. The SmartBolts indicator works on the most accurate principle for tension measurement – actual fastener elongation under load.
 
SmartBolts® Provide Visual Indication of TENSION 
 
FACT: It is tension, not torque that securely fastens your bolted joints together.
FACT: In most cases, torque wrenches cannot measure bolt tension accurately.
FACT: Unknown friction factors can dramatically reduce the accuracy of using torque measurement to establish proper bolt tension.
(And can ‘fool’ the installer into thinking the joint is tight!)

The use of torque wrenches to establish bolt tension may only be accurate to +/- 30% at best, because of unknown variations of the coefficient of friction. Factors affecting this coefficient include the material and size of the bolt, nut and washer, type of plating, surface smoothness, machining accuracy, corrosion or wear on the threads, presence and type of thread lubricant, the number of times a bolt has been previously tightened, and many other factors.  Fastener manufacturers often provide torque specifications for tightening various bolts to establish a required tension. However these torque specs are only accurate for one coefficient of friction and thus cannot account for inevitable changes in friction. Worse, even these potentially misleading specs are often not available in field applications, or their use is impractical or poorly administered.  Direct tension indicators, in contrast, respond to fastener tension ONLY, excluding the many factors affecting torque. Tension (also called preload or clamp force) is the one critical component ensuring your bolted joint is securely “tight”. 
 

Benefits

  • Easy to use – visual indication – no contact with the fastener required
  • Measures tension, a more accurate measure of “tightness” than torque
  • Accurate to +/- 10% of design tension
  • Reusable
  • No special tools or training required
  • Long service life
  • Design Tension customizable in design phase

See Product Demo - Click Below

HexHead Capscrew DTI SmartBolts Characteristics*

  • Size Ranges: 7/16″ (M10) to 1 1/4 “ (M32)
  • Available Grades: Grade 5, Grade 8, Class 8.8, Class 10.9 — for others contact us
  • Available Finishes: Clear zinc, black oxide, yellow zinc, for others contact us
  • Threading: Partial or full
  • Grip lengths: Minimums apply to fully threaded bolts, contact us
  • Design tension range: 40-90% of Proof Load
  • Accuracy: +/- 10% of design tension
  • Operating temperature range: -20 degrees C to 75 degrees C / -4 degrees F to 167 degrees F
  • Strength reduction as a result of modification: Generally only in smaller and fully threaded bolts.

*Contact us if you’re interested in other externally wrenched bolt designs or for possible stud designs.