Post-emulsifiable ZL-27A is a Level 3, high-sensitivity Type 1 penetrant designed for inspections which require maximum process control and reliability, such as safety-critical aerospace testing.
Since ZL-27A is not water soluble, there is minimal risk of this penetrant being removed from a fine or shallow defect through over-washing to provide the highest reliability of any penetrant inspection method.
ZL-27A has a high flash point and provides long tank life when used in open dip tanks, but this penetrant can also be applied in a variety of other ways, including electrostatic spray.
To remove surface ZL-27A penetrant before developer application, use ZE-4E Method B lipophilic emulsifier or ZR-10E Method D hydrophilic emulsifier can be used.
ZL-27A is listed on the QPL SAE AMS 2644 Qualified Product List and is approved for use by Pratt & Whitney.