Hi Harry
I could not agree more. Even elastic will only stretch to a certain
point to return to its original length one over stretched it is always
to slack.
I remember the classic Cockenzie boiler test in Scotland a number of
years ago I think the plate was 8 inch thick if my memory serves me
I think that there are possibly three reasons that the units are tested to
such pressures that don't necessarily have any metallurgical bearing:
1) Users may have a tendency to raise the pressure setting on their pressure
relief valves above what the factory intends. Since the majority of prv's
At 12:09 PM 3/14/05 -0600, you wrote:
1) Users may have a tendency to raise the pressure setting on their
pressure relief valves above what the factory intends.
A bad habit to get into, but even so this cannot justify a test
standard of 300% of WP.
2) Pressure gauges are not normally
Excellent commentary Harry. Much needed. If you would post (perhaps you already have) the the MLS and STIG sites, this would really get your words out. Whether or not they are heeded is another matter, but you got the word out and that is what is improtant.
Noel
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