UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 139
Default pneumatic compressor gas tightness question.

I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually gas
tight or do they have a normal amount of leakage back to the air inlet port?
  #2   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 6,938
Default pneumatic compressor gas tightness question.

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)

--
Tim Lamb
  #3   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 139
Default pneumatic compressor gas tightness question.

On 01/03/2021 12:55, Tim Lamb wrote:
In message , SH writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and
joints and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)


good question but I have never seen any small print to say that domestic
grade compressors must have their pressure vessels checked annually.....

That would also mean party balloons & bicycle tyres would have to be
checked as they are also technically pressure vessels! :-)
  #4   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,080
Default pneumatic compressor gas tightness question.

On 01/03/2021 13:22, SH wrote:
On 01/03/2021 12:55, Tim Lamb wrote:
In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80
psi whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and
joints and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are
expecting too much for a modestly priced device. 5 minutes for 40 psi
is rather a lot although the initial pressure will drop as the
compressed air cools.

Is your household insurer aware that you have a pressure vessel
subject to annual testing at your home?:-)


good question but I have never seen any small print to say that domestic
grade compressors must have their pressure vessels checked annually.....

That would also mean party balloons & bicycle tyres would have to be
checked as they are also technically pressure vessels! :-)


So is your pressure cooker - and that's a proper one with even a
"testable" safety valve.
  #5   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default pneumatic compressor gas tightness question.

On Mon, 1 Mar 2021 12:37:18 +0000, SH wrote:

I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually gas
tight or do they have a normal amount of leakage back to the air inlet port?


I have noticed 'leaks' from a couple of places in the past. One being
the water drain screw underneath and the other the pressure release
valve in the starter solenoid or the non return valve.

If you put the end of the outlet hose in a jar of water you should see
if it's leaking 'from' the system or leaking 'past' any non-return /
start back-pressure release valves etc (the one that goes 'Psssthhh!'
when the compressor shuts off when at full pressure).

Cheers, T i m


  #6   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 6,938
Default pneumatic compressor gas tightness question.

In message , Steve Walker
writes
On 01/03/2021 13:22, SH wrote:
On 01/03/2021 12:55, Tim Lamb wrote:
In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80
psi whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and
joints and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they
actually gas tight or do they have a normal amount of leakage back
to the air inlet port?

I have two compressors with the same feature. I think you are
expecting too much for a modestly priced device. 5 minutes for 40 psi
is rather a lot although the initial pressure will drop as the
compressed air cools.

Is your household insurer aware that you have a pressure vessel
subject to annual testing at your home?:-)

good question but I have never seen any small print to say that
domestic grade compressors must have their pressure vessels checked
annually.....
That would also mean party balloons & bicycle tyres would have to be
checked as they are also technically pressure vessels! :-)


So is your pressure cooker - and that's a proper one with even a
"testable" safety valve.


Don't insure with the NFU mutual is another answer:-)

--
Tim Lamb
  #7   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2
Default pneumatic compressor gas tightness question.

On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)




My understanding is that the requirement for annual testing is when
the pressure x volume exceeds 250 bar.litres

120 psi is less than 10 bar so no inspection in this case

John
  #8   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default pneumatic compressor gas tightness question.

On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

snip

I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)


AFAIK there is no (mandatory) requirement to have such placed under
the regulations if it's under 250 bar/l.

So, if the OP's compressor is 25l and 120psi (8.3 bar) then it's only
210 bar/l so well under the threshold (and likely why the regulations
are set at that level or compressors are made to that spec).

https://www.hse.gov.uk/pubns/indg178.pdf

It looks like the regulation applies to all pressure cookers though.
;-)

Cheers, T i m


  #9   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 62
Default pneumatic compressor gas tightness question.

Am 01.03.2021 um 15:29 schrieb T i m:
[..]

AFAIK there is no (mandatory) requirement to have such placed under
the regulations if it's under 250 bar/l.

So, if the OP's compressor is 25l and 120psi (8.3 bar) then it's only
210 bar/l so well under the threshold (and likely why the regulations
are set at that level or compressors are made to that spec).

nitpicking:
Bar*l not bar/l

  #10   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default pneumatic compressor gas tightness question.

On Mon, 1 Mar 2021 15:48:27 +0100, Matthias Czech
wrote:

Am 01.03.2021 um 15:29 schrieb T i m:
[..]

AFAIK there is no (mandatory) requirement to have such placed under
the regulations if it's under 250 bar/l.

So, if the OP's compressor is 25l and 120psi (8.3 bar) then it's only
210 bar/l so well under the threshold (and likely why the regulations
are set at that level or compressors are made to that spec).

nitpicking:
Bar*l not bar/l


Thanks, the '/' wasn't indented to indicate 'divide (or per) but just
as a separator between bar and it but could be confusing if not seen
along with the formal regs etc.

In the linked regs it was generally written out as 'bar litres'.

Cheers, T i m




  #11   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 25,191
Default pneumatic compressor gas tightness question.

On 01/03/2021 12:37, SH wrote:

I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.


That sounds rather excessive...

(I have a similar compressor, and it will typically not refire in many
many hours (days even) with no air demand.

However it does not take much of a leak to cause what you are seeing.
Typically if I have a nailer hooked up to it, and put it down on the
workbench between uses - sometimes you get a slight leak from the quick
connect PCL connector - depending on hose angle etc, and then a few mins
of that leak will be enough to prompt it to recharge.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.


Did you check the drain valve?

This then leaves the compressor pump bit itself... are they actually gas
tight or do they have a normal amount of leakage back to the air inlet
port?


It it an "oil free" using? If not has it got (enough) oil in it? Have
you checked all the hoses as well as the joins?



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #12   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 875
Default pneumatic compressor gas tightness question.

SH submitted this idea :
Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.


You have a leak somewhere, check the drain valve at the bottom of the
tank; any airlines you have attached. Tap water, with a drop of Fairly
liquid and a soft paint brush makes finding a leak easy.

My DIY garage compressor normally holds full pressure for days, with
nothing connected to it.
  #13   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 6,938
Default pneumatic compressor gas tightness question.

In message , John
writes
On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)




My understanding is that the requirement for annual testing is when
the pressure x volume exceeds 250 bar.litres

120 psi is less than 10 bar so no inspection in this case


Hmm.. £120/yr. potential saving. I'll check my volumes...


--
Tim Lamb
  #15   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,699
Default pneumatic compressor gas tightness question.

Yes, lots of dangerous stuff in the home. Remember CRTs? Now its more likely
a lithium battery burning the house down, or an exploding electrolytic
capacitor taking an eye out if you are working on an open PC.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"SH" wrote in message
...
On 01/03/2021 12:55, Tim Lamb wrote:
In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually gas
tight or do they have a normal amount of leakage back to the air inlet
port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)


good question but I have never seen any small print to say that domestic
grade compressors must have their pressure vessels checked annually.....

That would also mean party balloons & bicycle tyres would have to be
checked as they are also technically pressure vessels! :-)





  #16   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 8,019
Default pneumatic compressor gas tightness question.

On 01/03/2021 14:18, Tim Lamb wrote:


Don't insure with the NFU mutual is another answer:-)

I don't recall them having such a restriction on my house insurance.

I was mildly amused on shifting my car insurance to them that one of
their questions was "Would you ever carry more than 3000 shotgun
cartridges in your car".

I imagine it might be quite exciting if that quantity went off.
  #17   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 8,019
Default pneumatic compressor gas tightness question.

On 01/03/2021 16:46, Brian Gaff (Sofa) wrote:
Yes, lots of dangerous stuff in the home. Remember CRTs? Now its more likely
a lithium battery burning the house down, or an exploding electrolytic
capacitor taking an eye out if you are working on an open PC.
Brian

IME CRTs don't go off very spectacularly. Long long ago my father sought
to make one safe (while I watched) by wrapping it in multiple layers of
blankets and sacking, then lobbing bricks at it from a distance. After a
number of failed attempts, the gun extension just snapped off with no
detectable "bang". (By the end of the war he was training people in how
to blow stuff up. He won't have done a "stored energy" sum and, on
thinking about it, there's not much stored energy even in an old-style
45 degree tube).
  #18   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 6,938
Default pneumatic compressor gas tightness question.

In message ,
newshound writes
On 01/03/2021 14:18, Tim Lamb wrote:

Don't insure with the NFU mutual is another answer:-)

I don't recall them having such a restriction on my house insurance.

I was mildly amused on shifting my car insurance to them that one of
their questions was "Would you ever carry more than 3000 shotgun
cartridges in your car".

I think somewhere there is a limit related to carrying ammunition in a
shoot vehicle.

I imagine it might be quite exciting if that quantity went off.

Not sure if Tim would be pleased but there are moves afoot to cease
using lead for shot.

--
Tim Lamb
  #19   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 6,938
Default pneumatic compressor gas tightness question.

In message , John
writes
On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)




My understanding is that the requirement for annual testing is when
the pressure x volume exceeds 250 bar.litres

120 psi is less than 10 bar so no inspection in this case


Sadly my two are 100L and 150L if I have the sums right.



--
Tim Lamb
  #20   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 1,591
Default pneumatic compressor gas tightness question.

On 01/03/2021 18:24, Tim Lamb wrote:
In message ,
newshound writes
On 01/03/2021 14:18, Tim Lamb wrote:

Â*Don't insure with the NFU mutual is another answer:-)

I don't recall them having such a restriction on my house insurance.

I was mildly amused on shifting my car insurance to them that one of
their questions was "Would you ever carry more than 3000 shotgun
cartridges in your car".

I think somewhere there is a limit related to carrying ammunition in a
shoot vehicle.

I imagine it might be quite exciting if that quantity went off.

Not sure if Tim would be pleased but there are moves afoot to cease
using lead for shot.


I'm surprised its still in use. Certainly been banned for fishing for
quite a while.

What alternative, depleted uranium? I guess the Rolls Royce solution
will be Tungsten.




  #21   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 8,019
Default pneumatic compressor gas tightness question.

On 01/03/2021 19:46, Fredxx wrote:
On 01/03/2021 18:24, Tim Lamb wrote:
In message ,
newshound writes
On 01/03/2021 14:18, Tim Lamb wrote:

Â*Don't insure with the NFU mutual is another answer:-)

I don't recall them having such a restriction on my house insurance.

I was mildly amused on shifting my car insurance to them that one of
their questions was "Would you ever carry more than 3000 shotgun
cartridges in your car".

I think somewhere there is a limit related to carrying ammunition in a
shoot vehicle.

I imagine it might be quite exciting if that quantity went off.

Not sure if Tim would be pleased but there are moves afoot to cease
using lead for shot.


I'm surprised its still in use. Certainly been banned for fishing for
quite a while.

What alternative, depleted uranium? I guess the Rolls Royce solution
will be Tungsten.


It is banned over wetlands, not sure how effectively. A recent survey
showed that virtually all pheasants sold contained lead shot.

https://www.bbc.co.uk/news/science-environment-56158777

The only realistically affordable alternative is steel shot and that
does not have the same effective range.
  #22   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 25,191
Default pneumatic compressor gas tightness question.

On 01/03/2021 14:20, John wrote:
On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?


I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)




My understanding is that the requirement for annual testing is when
the pressure x volume exceeds 250 bar.litres


What about if you have multiple compressors that are individually under
the limit?


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #23   Report Post  
Posted to uk.d-i-y
jon jon is offline
external usenet poster
 
Posts: 434
Default pneumatic compressor gas tightness question.

On Mon, 01 Mar 2021 17:34:00 +0000, newshound wrote:

On 01/03/2021 16:46, Brian Gaff (Sofa) wrote:
Yes, lots of dangerous stuff in the home. Remember CRTs? Now its more
likely a lithium battery burning the house down, or an exploding
electrolytic capacitor taking an eye out if you are working on an open
PC.
Brian

IME CRTs don't go off very spectacularly. Long long ago my father sought
to make one safe (while I watched) by wrapping it in multiple layers of
blankets and sacking, then lobbing bricks at it from a distance. After a
number of failed attempts, the gun extension just snapped off with no
detectable "bang". (By the end of the war he was training people in how
to blow stuff up. He won't have done a "stored energy" sum and, on
thinking about it, there's not much stored energy even in an old-style
45 degree tube).


wrapping and breaking the neck with an axe is quite safe.
  #24   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2
Default pneumatic compressor gas tightness question.

On Mon, 1 Mar 2021 23:33:08 +0000, John Rumm
wrote:

On 01/03/2021 14:20, John wrote:
On Mon, 1 Mar 2021 12:55:05 +0000, Tim Lamb
wrote:

In message , SH
writes
I have a Stanley air compressor with a 25 litre storage vessel.

when I start it, it pumps up to 120 psi and then the motor cuts out.

Over typically 5 minutes, the air pressure will decay slowly to 80 psi
whereby the compressor motor restarts.

This happens when I am not using any air tools.

I have used a can of gas leak detector and tested all unions and joints
and I can confirm there are no leaks.

This then leaves the compressor pump bit itself... are they actually
gas tight or do they have a normal amount of leakage back to the air
inlet port?

I have two compressors with the same feature. I think you are expecting
too much for a modestly priced device. 5 minutes for 40 psi is rather a
lot although the initial pressure will drop as the compressed air cools.

Is your household insurer aware that you have a pressure vessel subject
to annual testing at your home?:-)




My understanding is that the requirement for annual testing is when
the pressure x volume exceeds 250 bar.litres


What about if you have multiple compressors that are individually under
the limit?


In that case as long as they are not linked to form a bigger system
then I think they are all not not subject to mandatory testing.

If these are owned by an employer it may be a case of checking with
the insurer, and also considering carrying out and recording a
systematic in-house check to look for any obvious faults.

Usual disclaimer IANAL.



--
Regards

John
  #25   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 870
Default pneumatic compressor gas tightness question.

newshound wrote:
On 01/03/2021 16:46, Brian Gaff (Sofa) wrote:
Yes, lots of dangerous stuff in the home. Remember CRTs? Now its more
likely
a lithium battery burning the house down, or an exploding electrolytic
capacitor taking an eye out if you are working on an open PC.
Brian

IME CRTs don't go off very spectacularly. Long long ago my father sought
to make one safe (while I watched) by wrapping it in multiple layers of
blankets and sacking, then lobbing bricks at it from a distance. After a
number of failed attempts, the gun extension just snapped off with no
detectable "bang". (By the end of the war he was training people in how
to blow stuff up. He won't have done a "stored energy" sum and, on
thinking about it, there's not much stored energy even in an old-style
45 degree tube).


CRTs can be energetic.

You just have to know how to tease them,
to max the output.

One of our fine grad students in the chem department,
decided the picture tube in his colour TV was "gassy".
That was the story that was told to me. He brings
the tube into work, sets it up on a bench at one
end of the lab.

He heats the neck of the tube with a torch. Presumably
this heating was done where there was a sealing
nipple or something. Well, he only got to apply the
torch for a few seconds, before the thing imploded.

It blew glass the length of the lab. There were flecks of
glass down at the other end of the lab, a distance of
around 50 feet.

I couldn't believe it. I wasn't there when this happened,
but I used that lab, and I was finding bits of glass
for several weeks afterwards, in all sorts of weird spots.
You'd find pieces in sinks and so on.

Most of the glass stayed up the head end of the room, but
there was still glass all the way down at the end. I just
couldn't imagine how the pattern ended up like that.

I've imploded picture tubes at the city dump (landfill)
back when I worked a maintenance job, and none of those
did anything spectacular. They were all duds. I put a
brick through the front of one and... nothing. Just loss
of vacuum and nothing thrown back at me.

And the guy who carried out this feat, I don't know
if he ever graduated. He would make one hell of a TV
repair man :-) I could see him bringing his Bunsen
burner over to your house now.

Paul


  #26   Report Post  
Posted to uk.d-i-y
Lee Lee is offline
external usenet poster
 
Posts: 698
Default pneumatic compressor gas tightness question.

On 01/03/2021 14:11, T i m wrote:
snip

I have noticed 'leaks' from a couple of places in the past. One being
the water drain screw underneath and the other the pressure release
valve in the starter solenoid or the non return valve.


snip

+1 Mechanic mate just changed both the unload valve and non-return valve
to cure same fault on a compressor.

I'd start with the non-return valve, they are cheap and it's the most
likely to be crudded up. Machine Mart is one of many places to get them,
if you have one handy.

Lee

  #27   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default pneumatic compressor gas tightness question.

On Tue, 2 Mar 2021 11:07:32 +0000, Lee
wrote:

On 01/03/2021 14:11, T i m wrote:
snip

I have noticed 'leaks' from a couple of places in the past. One being
the water drain screw underneath and the other the pressure release
valve in the starter solenoid or the non return valve.


snip

+1 Mechanic mate just changed both the unload valve and non-return valve
to cure same fault on a compressor.

I'd start with the non-return valve, they are cheap and it's the most
likely to be crudded up. Machine Mart is one of many places to get them,
if you have one handy.


I have a silent (Bambi) 25l compressor on a 25l cylinder compressor
and if left pressurised (and it holds it's pressure for ages (days /
weeks) the non return valve between the piston and the rest of the
system can become stuck (closed).

I just undo the body, release the rubber tip and do it back up and
it's good to go again.

I'm guessing it could easily also become contaminated, not allowing it
to seat properly and so allowing some 'leak past' that you may be
suffering (that wouldn't be traced as a conventional leak from any of
the system etc).

Good luck in your quest. ;-)

Cheers, T i m

Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Compression fitting tightness on plastic pipe? Mathew Newton[_2_] UK diy 15 April 20th 19 12:21 AM
Are gas fitters allergic to gas tightness testing? Tim Watts[_3_] UK diy 28 August 5th 14 04:23 PM
Natural Gas - Pictures and Diagrams of Natural Gas, Natural Gas Furnace, Natural Gas Grill, Natural Gas Heater, Natural Gas Water Heater and Natural Gas Vehicle [email protected] Home Ownership 3 June 18th 07 07:34 AM
Natural Gas - Pictures and Diagrams of Natural Gas, Natural Gas Furnace, Natural Gas Grill, Natural Gas Heater, Natural Gas Water Heater and Natural Gas Vehicle [email protected] Home Repair 1 June 18th 07 06:32 AM
Pneumatic Finish Nailer or pneumatic stapler Danny Home Repair 10 March 26th 05 06:09 PM


All times are GMT +1. The time now is 03:15 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"