Forum Technical Discussions      Re: PT dwell time variations in reference to temperature extremes Posted by: Michel Couture (PID_2805), E-mail: Address, on December 27, 2008 at 19:59 : In Reply to: Re: PT dwell time variations in reference to temperature extremes posted by : S.V.Swamy , E-mail: Address, on December 27, 2008 at 00:50 : Hi Jim, I totally agree with Swamy. Even more I do remember 20 years ago when I got into NDT and dealing mostly with Military Standard that we (in the Canadian Air Force) used MIL-I-6868 to select the penetrant and developer that was compatible with the job we had to do. I do know if it still exist today or if it has been superseded by another code. But, in the end, if you consult the manufacturer's spec. for a product and stay within the temperature range of the code your working to, you shouldn't have any problem. Remember keep it simple and don't try to reinvent the wheel. Many people have spent countless hours to come up with with is already establish and it work. Cheerio's Michel ----------- Start Original Message ----------- : What is vague about them? And the manufacturers provide enough literature, if needed. If the temperature is too low, viscosity will be too high and penetration will not take place properly. If the temperature is too high, the penetrant will dry out and will again not penetrate. If in doubt, use test coupons at the same temperature and see whether you are able to pick up the needed indications. : Swamy : NDT Guru : Hyderabad, India : : Does anybody have....... or know where i can find.... a table outlining penetrant and developer dwell times with regards to temperature? I know certain codes and standards provide guidelines but I'm looking for something less vague. ------------ End Original Message ------------ Follow Ups: Re: PT dwell time variations in reference to temperature extremes Justin Lehmann 23:31 Jan-06-2009 (0) Post a Followup: Name: E-Mail: Subject: Comments: ----------- Start Original Message ----------- : Hi Jim, : I totally agree with Swamy. Even more I do remember 20 years ago when I got into NDT and dealing mostly with Military Standard that we (in the Canadian Air Force) used MIL-I-6868 to select the penetrant and developer that was compatible with the job we had to do. I do know if it still exist today or if it has been superseded by another code. But, in the end, if you consult the manufacturer's spec. for a product and stay within the temperature range of the code your working to, you shouldn't have any problem. Remember keep it simple and don't try to reinvent the wheel. Many people have spent countless hours to come up with with is already establish and it work. : Cheerio's : Michel : : What is vague about them? And the manufacturers provide enough literature, if needed. If the temperature is too low, viscosity will be too high and penetration will not take place properly. If the temperature is too high, the penetrant will dry out and will again not penetrate. If in doubt, use test coupons at the same temperature and see whether you are able to pick up the needed indications. : : Swamy : : NDT Guru : : Hyderabad, India : : : Does anybody have....... or know where i can find.... a table outlining penetrant and developer dwell times with regards to temperature? I know certain codes and standards provide guidelines but I'm looking for something less vague. ------------ End Original Message ------------ Optional Link URL: Example: "http://www....html". Alternative write "http://www.ndt.net/wshop/attach/filename.htm" if you transfered a filename.htm via FTP Page Title: is important! Optional Image URL: http://www....gif Attention! Please click the button only once. This may take a moment to process Forum Technical Discussions Help