TM 1-1500-204-23-7
Table 3-1. Minimum Penetration Time For Penetrants
Water
Post
washable
emulsified
Type of
penetration
penetration
Material
Form
discontinuity
time (minutes)
time (minutes)1
Plastics
All
Cracks
5 to 30
5
Glass
All
Cracks
5 to 30
5
Carbide-tipped
Lack of fusion
30
5
tools
Porosity
30
5
Cracks
30
20
Titanium and
All
N/R
20 to 30
high tempera-
ture alloys
All metals
All
Stress or inter-
N/R
240
granular corro-
sion
1For parts having a temperature of 60 °F or higher.
2Precision castings only
(2)
Nonaqueous wet developers. Nonaqueous wet developers can be applied by one of the following methods:
Dipping
Spraying (whenever possible)
Dusting
Brushing (not preferred)
Flow-on
(3)
Dry developers. Dry developers can be applied by one of the following methods:
3-8
