Name: Kelly M.
Status: Student
Age: 14
Location: N/A
Country: N/A
Date: October 2003
Question:
What are the advantages of electrically charging an object before spray
painting it?
Replies:
Elactrostatic spraying is a common industrial method of coating. Usually the spray gun is
charged and the object is grounded. The operator must also be insulated from the charged
spray gun. The reverse (grounded gun / operator) can also be used. The principle is that
the particles of coating (either liquid or powder) are charged with a charge opposite that
of the object being coated. The advantage is that since opposite charges attract the
coating will be more efficiently deposited on the object being sprayed.
"Over spray" -- spray that does not hit the object -- is minimal because of the
electrostatic charging. More even distribution of the coating also occurs, because the
spray particles can get into cracks, and scratches. In fact, the "back side" of the
object is coated with almost the same efficiency as the "front side" because spray
particles that miss the object "wrap around" the object and are deposited on the rear
of the article.
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