Our largest calibration rig, Mk15, was built to calibrate balances with load ranges typical for our T1500 wind tunnel. The high loads are applied automatically through pressurized air actuators and thus no dead weights are used. The model end of the balance to be calibrated is installed vertically in the center of the rig. A calibration sleeve is mounted to the sting end and to this sleeve several tension rods are connected.
Load cells are mounted on the tension rods between the calibration sleeve and the force actuators. The deflection of the calibration sleeve is measured and the applied loads are corrected for the deflections. Load application, data acquisition and balance matrix calculation are performed with a dedicated computer.
The load cells are calibrated in another dedicated rig, Mk10, where dead weights are used as reference. The dead weights are applied automatically through a lever with a 10:1 ratio.
To calibrate balances rated up to 6 kN we use our Mk6 calibration rig. In this rig manually applied dead weights are used. There is a lever with the ratio 5:1 between the load and the calibration sleeve. The balance and calibration sleeve are mounted vertically and the loads are applied in the model end of the balance. Slow moving actuators are used to reposition the calibration sleeve to its initial position due to balance deflection under load. Up to 6 components can be loaded simultaneously.
A third balance calibration rig is the Mk5 which is rated at 3 kN. In this rig the balance and calibration sleeve are mounted horizontally and all loads are from dead weights without any load amplification. Repositioning from load deflection is done manually. Although 6 components can be loaded simultaneously this rig is more labour intensive and for that reason used for more unusual applications that mostly use less than 6 components.
To calibrate quite small balances that are mainly used for stores testing our Mk8 calibration rig is used. This rig is used for both sting balances used in our two-sting rig and for pylon mounted balances. Up to 6 components can be loaded simultaneously. Loading is performed with dead weights. Slow moving actuators is used to reposition the calibration sleeve to its initial position due to balance deflection under load.
STARCS Mk15. Our Mk15 calibration rig uses 14 load actuators and load cells.
STARCS Mk10. A load cell is being calibrated in our Mk10 calibration rig.
STARCS Mk6. The vertically mounted balance and calibration sleeve together with repositioning actuators.