Problem Solving Forum
April 11 - April 17, 2011
How clean must the compressed-air supply be for blast cleaning, blow down and painting? How is cleanliness of the air determined?
Selected Answers
From
Pongpawut Onkaew of Akzo Nobel Coatings on
June 16, 2011:
Conduct a blotter test in ...read more
Conduct a blotter test in accordance with ASTM D 4285, Acceptance criteria is no visible oil, water or other contamination allowed.
From
Aldrin Cordovez of Kuwait Oil Company on
May 28, 2011:
A compressed air free fro ...read more
A compressed air free from any form of contaminants is necessary before its usage. Its cleanliness shall be checked using the blotter test method. Any traces of water, oil and foreign matters shall not be visible on the blotter test paper before it can be utilized for such purposes.
From
Gary M of T & G Services on
April 14, 2011:
It is critical that the a ...read more
It is critical that the air supply is not contaminated with oil or water during all the processes you listed. To ensure that the air is dry and clean, conduct a blotter test prior to starting each work shift and at reasonable intervals throughout the day. If contaminants are evident on the blotter test, all filters and driers that should be present in the supply line must be opened and blown out until the air is clean and passes the blotter test. If you can't achieve a passing test, added filters can be used, or the air source should be replaced.
From
Carl Havemann of www.corrosioneducation.co.za on
April 14, 2011:
There are two contaminant ...read more
There are two contaminants to test for, oil and moisture. Check for oil using the Drager Oil Mist 1/a tube, Ref 6733031. Acceptance criteria is that no oil is allowed. To check for moisture, blow the compressed air onto clear glass for 30-60 seconds, then check for condensation. Acceptance criteriais that no moisture allowed. [A 5-minute test is too long, in my opinion]
From
Lee Edelman of Independant on
April 13, 2011:
The air supply must be fr ...read more
The air supply must be free of oil, water and other contaminants. Cleanliness is checked by doing a blotter test at the air manifold. The air supply should have moisture traps in-line and a proper aftercooler system.
From
remko tas of Futuro SRL on
April 13, 2011:
Expose a sheet of white p ...read more
Expose a sheet of white paper (taped to a board) at a distance of 1 meter for 1 minute to the airflow from the compressed air supply.There should be no visible oil stains on the white paper.
From
John Gascoigne of Puget Sound Coatings on
April 12, 2011:
The air needs to be clean. Test ...read more
The air needs to be clean. Test for cleanliness by blowing into a white rag or a clear glass or plastic container for 5 minutes.