12:04 Dec-05-2009 aldo Engineering Italy, Joined Jan 2009 39
performance mercury vapour lamp
I readed the parameters that have influence on life mercury vapor lamp...They are:
voltage fluctutations, dirt on filters, tarnishing of reflectors, etc..
The question is:
Can have influence the type or the quality of the isotope mercury uses in lamps?
I do not read nothing on this issue and i want the your opinion if is possible..
tanks and best regards
I think what we are looking at here are the factors that will affect the longivity and the detectability of defect using a Black Light. Anything that is inside the glass shell is out of your control. Not only that, those lamps were manufactured according to a proven and quality control process.
What is important for us in regards to MT or PT is that the lamp be clean to allow maximum light emission therefore increasing your chance of detection. Also, dirt on the lamp and or on the filter also decreases its life because of the hot spots that it will create on its surface. It may results in a filter cracking for example, which could be dangerous for anyone that happen to be looking at the light. Mind you, why should you be looking at the light in the first place?
I have done this question because in one quiz there was the answer where it spoke if the quality of isotope mercury has o has not any influence on quality and intensity black light and on its life...The correct answer was that on performance mercury vapour lamp was influence by type of isotope mercury....
I totally agree with you if you look at it this way. Unfortunately, some people (the ones writing those exams) seems to really like to split hair and as you can see, I don't have much to spare. But seriously, they are technically right, yet as a technician doing a PT inspection it is not something you have control over. Like I said previously, the bulb is made a certain way, under specific control in the manufacturer's plant. In other word, you get what you get. As long as you buy the buld that is design for the lamp you are using, everything should be fine. What we have control over and what will affect our inspection is what we spoke about previously ie. cleanilness of the bulb and filter. Yet that is something that I find very few technicians do.
It's not like what some people ask about UT instrument. They have rechargeable 'D' cell batteries that cost an arm and a leg from a supplier, but what appears to be the same one at a local story is a third of the price. In this case, it is different. The difference in price very often is tied in with the amperage rating. So you have a choice: a) you buy the cheap battery that will last only two hours or b) the expensive one that will last you eight hours?