Non Destructive Testing // Developers

DUBL-CHEK D-100 developer consists of refined white particles suspended in isopropyl alcohol that produces enhanced sensitivity for locating tight flaws. D-100 developer pulls flaw-entrapped penetrant to the part surface and creates a contrasting vivid white background. Complies with low sulphur and low halogen requirements. 

• QPL-AMS-2644 listing
• MIL-I-25135 Revisions C, D & E
• ASME Code NDT, Sec V
• SAE AMS 2644

1. Application: Apply penetrant only to clean, dry surfaces by spraying, flowing, brushing or dipping.  
2.Dwell Time: A 10-minute dwell time is suggested, although in many cases five minutes will suffice. When particularly tight cracks are suspected, or the part is especially critical, the dwell time may be extended to 30 minutes or longer. Allow the penetrant to drain from the part surface back into the penetrant tank to conserve material.  
3. Removal: Use the appropriate washing method to remove the excess penetrant from the surface.  
4. Drying:
a) A re-circulating oven set no higher than 71ºC is suggested. Leave the part in the oven just long enough to evaporate surface moisture. Drying is improved by using pressurised air to disperse and remove as much excess water as possible before placing the part into the oven.
b) When solvent remover is used, allow the surface to dry completely before applying the developer.
5. Developing: After agitating the D-100 suspension, evenly spray a light slightly wet coating of developer onto the dry surface of a part. An overly wet application will blur indications; an overly dry application lacks full developing action. Two or three light applications work better than a single heavy application. Too heavy an application may conceal indications. If D-100 is to be applied with a paint spray gun, the spray gun should have a vaporising tip, the spray tank should be pressurised to 15-30 pounds of pressure, and have a stirrer to keep the powder in suspension.  
6. Inspection: Inspect parts under appropriate light.