State-of-the-art Engineering Equipment

EM 309.01 | Screw Efficiency Apparatus

  • Length: 450 mm
  • Width: 400 mm
  • Height: 260 mm
  • Weight: 27 kg
Technical Specification
The main element of the unit is a slotted, elastically deformable steel block. By tightening the bolt joint, the slotted area is deformed, thereby generating an axial tension force in the bolt. The resulting deformation is recorded by a mechanical dial gauge, and is directly related to the bolt tension force generated. The bolt joint is tightened and slackened using a special torque wrench, which can be set sensitively with the aid of a threaded spindle. By using an axial bearing, the head friction of the bolt can be largely excluded, so that only the friction of the threaded joint is measured.
Experimental Capabilities
  • Axial tension force in a bolt joint dependent on the tightening torque or the elastic deformation of a slotted block.
  • Measurement of the breakaway torque, including for different fitting situations of the bolt joint.
  • Measurement of thread friction and overall friction.
Scope of Delivery
  • 1 experimental unit.
  • 1 set of bolts in transparent container.
  • 1 set of instructional material.
  • Experiment on the correlation between the tension force and tightening torque of bolts.
  • Bolt size M8x100, wrench jaw size 13mm.
  • Elastic deformation of a slotted block by the bolt.
  • Determining the tightening and breakaway torque with a mechanical torque measuring device.
  • Two dial gauges.
  • Sensitive torque setting by hand wheel.
Tension force
  • 40kN.
  • Force/travel constant:
  • 20kN/mm (on slotted block).
  • Tightening torque
Torque/travel constant
  • 10Nm/mm (on torque measuring device)
  • Dial gauge:
  • 0…10mm.
  • Graduation: 0.01mm.