Quantitative Quality Indicator Test Piece Shims (QQI)
Quantitative Quality Indicators (QQI) are magnetic particle test piece shims with artificial defects used to verify field direction and relative strength. QQI's are also used to balance multi-directional fields and to increase productivity by minimizing magnetizing shots. The QQI indicator shims are packaged in sets of five.
Part Numbers (all QQIs come in a set of five shims)
Remove the corrosion-resistant film from the QQI before use. Solvents such as SKC-S, acetone, or an adhesive remover (Goof-Off or equivalent) are recommended. Use caution when handling to prevent damage or distortion. QQIs must be placed in intimate contact with the notches facing inward towards the part surface. Permanent adhesive such as cyanoacrylate (super glue or equivalent) is recommended. Attach the QQI conforming to the part surface with no gaps or loose areas. No adhesive should remain on the outer inspection surface after the QQI is attached. Cellophane tape (Scotch Brand 191, 471, or 600 series) may be used to attach QQIs. Care should be taken to only cover the edges of the QQI so that the central notched area is clear. If the tape becomes loose, completely remove the QQI, clean and reattach with new tape.
Multi-directional applications are determined by setting the amperage of each direction individually, then balancing the fields when applied together.