Screw Withdrawal Force Meter
Screw withdrawal force is an indicator of the strength, density and shear modulus of wood. Therefore, Fakopp Kft has developed a portable screw withdrawal force meter. The applied screw diameter is 4mm, the length of the thread is 18 mm. The screw withdrawal force is a local parameter, but selecting a representative location on a beam, it can provide useful information in wooden structure evaluation.
Drive the screw into the wood material, perpendicular to its surface.
Connect the cable of the force transducer to the display unit R320.
Switch on the unit by pressing the “ON” button for 3 seconds.
Select the Peak hold function.
Start the screw withdrawal process by placing the mechanics over the screw. Catch the screw head by the fork of the force transducer.
Slowly turn the handle clockwise until the screw is removed. The speed of the withdrawal should be approximately 0.5 mm/s.
Record the maximal force value and press the “Max” button before the next test to reset the display.
Screw withdrawal mechanics with force transducer
Display unit, R320
Screws and screwdriver
Rechargeable battery and charger
Aluminium carrying box
10 special screws
User manual
Specification |
Details |
|---|---|
Force transducer capacity |
5 kN (survives 10kN) |
Temperature sensitivity |
less than 0.005%/Ko |
Hysteresis error |
less than 0.05% |
Repetition error |
less than 0.03% |
Operating temperature |
-10 °C to +40 °C |
Resistance |
350 Ω |
Material |
steel |
Manufacturer |
Kaliber MM Kft., Budapest, Hungary |
Force meter resolution |
5 N |
Display unit operation temperature |
+10 °C to +40 °C |
Battery |
4 pieces of AA size 1.5 V battery |
