Please enable JavaScript.
Coggle requires JavaScript to display documents.
Developers (Developers Form (Form d - Nonaqueous Type 1 Fluorescent…
Developers
Developers Form
-
-
Form b - Water Soluble
• group of chemicals that are dissolved in water and form a developer layer when the water is evaporated away
• apply by spraying it on the part, can use Dipping, pouring, or brushing the solution on to the surface but less desirable
-
• an even, pale white coating formed
-
-
Disadvantages: coating is translucent and provides poor contrast (not recommended for visual systems), indications for water washable systems are dim and blurred
Advantages: ease of coating entire part, white coating for good contrast can be produced which work well for visible and fluorescent systems
Form d - Nonaqueous Type 1 Fluorescent (Solvent Based) & Form e - Nonaqueous Type 2 Visible Dye (Solvent Based)
-
• Since the solvent is highly volatile, forced drying is not required.
-
-
-
-
Disadvantages: difficult to apply evenly to all surfaces, more difficult to clean part after inspection
Advantages: very potable, easy to apply to readily accessible surfaces, white coating for good contrast can be produced which work well for visible and fluorescent systems, indications show-up rapidly and are well-defined, provides the highest sensitivity
-
Form a - Dry Powder
-
• by dipping parts in a container of developer,
by using a puffer to dust parts with the developer,
or placing parts in a dust cabinet where the developer is
blown around.
• least sensitive, inexpensive
-
-
Advantages: indicarions tend to remain brighter and more distinct over time, easily apply
Disadvantages: does not form contrast background so cannot be used with visible systems, difficult to assure entire part surface has been coated
Functions
to pull the trapped penetrant material out of defects and spread it out on the surface of the part, so it can be seen by an inspector.
to create a white background, so there is a greater degree of contrast between the indication and the surrounding background.
fine developer particles both reflect and refract the incident ultraviolet light, allowing more of it to interact with the penetrant, causing more efficient fluorescence.
-
-