Baffling Vickers-Armstrongs "thing" identification please!

[Aaamusements]

Another item that was received with all the fire/emergency/military comms stuff. This one has everyone baffled!
It hasn't so far been identified as Fire Service by some in the know... so probably specifically military?

The gauge measures pressure in Atmospheres, but does not seem to join up with the other bits ( but it was originally fastened/cable tied up to the wiring of the other item).

The large box has knurled, O-ringed knobs to get into it. It contains a couple of aluminium boxes, one sealed and one with mesh and possibly some foam remains. Inside smells of old soap! There appears to be a pressure switch on it with external connector.

The other bit looks as though it has speakers in, but I'm not sure if they are... not had a chance to dismantle it either.

The other plate has the same V.R.49/ and is then labelled "EP.523".
It also has no patent number (and no "Applied For" stamp either!)

This has baffled many people... can you solve the mystery please?

[Nuvistor]

The one with the atmospheric gauge, is it an air filter? On some of the computer disk drives I worked on they had an air filter and the way to test if it was serviceable was to use an atmospheric gauge.

[G6Tanuki]

I can't think of any computer disk-drive whose air-filter would involve pressures up to 200 Atmospheres!

[Radio Wrangler]

200 atmospheres would be the charged pressure of a steel or aluminium gas cylinder back in that era, or it could be the running pressure of some hydraulic systems.

The flexy hose probably rules out oxygen as not many materials are safe with it at those pressures.

David

Monitoring gas (air) expansion cooling of an IR camera?

[Nuvistor]

Did not look at the scale, but it was just a thought. The ports on the box don't look as though they would seal at that pressure.

The ports on the box don't look as though they would seal at that pressure.

The Banjo coupling does though.

[Aaamusements]

Just to reiterate that the pressure gauge was not physically connected to anything but the hose from it was cable tied to the wiring loom of the item on the left.

Also the banjo coupling was loose in a box when received but it does fit the pressure type elbow on the box perfectly.

[ex seismic]

Not sure about the hose but I don' think I'd want to put 200 atmospheres in that box. Not close up to it anyway!

Gordon

[Stockden]

My initial thought was pressurized antenna feeders but 200 Atmospheres is way too high for that. Indeed, as Gordon says, I wouldn't to be anywhere near that box if was pressurized to that extent!

Hugh

[Radio Wrangler]

I would expect antenna feeder pressurisation stuff to use standard cylinder-mounted regulators probably with two ordinary round bourdon gauges for cylinder contents and output pressure. It only needs to be a low outlet pressure and no one wants to put full cylinder pressure through any more fittings than necessary.

David

[Silicon]

Could it be part of a Halon fire suppressant system? Halon gas suppresses fire but does not damage books and expensive equipment.

The box with the loudspeaker could be an early Doppler movement detector to sense if people were in the room.

Brendan

[Aaamusements]

Some interesting possibilities. I'll have to dismantle the other part when I'm next over there and see what I find.

[Radio Wrangler]

The lower end of the pressure gauge is shaded red, which implies danger happens if it runs out of something rather than if the pressure goes too high. This would fit with fire suppression or feeder pressurisation. The pressure range seems a bit high for Halon (usually stored as liquid in thin-walled pressure vessels) So maybe CO2 or Argon/Nitrogen mix? Or dry nitrogen for cables? Most normal pattern gauges are marked with what material they may be used with for example I have a regulator with twin gauges marked "Argon or CO2"
Not all gauge materials are compatible with all gases... copper can catalyse explosive decomposition in acetylene for example, and greases and plastics are no-no's with high pressure oxygen.

David

[russell_w_b]

Feeder pressure is usually only a few PSI above atmospheric and would include a dehydrator, unless the feeder contains SF6.

CO2 fire-drench equipment is bottle-pressure: tested to 3360 PSI. Halon is similar (but is now banned, of course). None of the argon, halon or CO2 fire-drench equipment I've seen has gauges on or any sort of metering, as all that is required is to discharge the bottles as quickly as possible in the space protected.

[Radio Wrangler]

The Argon cylinders I use now come charged to 230 bar. BOC et al have been replacing their cylinder stock with better grade steel and the charge pressure has been increased several times while I've been using them.

But thatArmstrong equipment is quite old, I think. With a 200 bar pressure gauge, I'd expect the normal max pressure in the system to be 100 or 130 bar. That would fit with steel cylinder pools of 40 years ago.

Whatever it is, it's on something that running out is considered to be a not good situation. There's a red band at the bottom, not one at the top.

David

[russell_w_b]

Originally Posted by Radio Wrangler

Whatever it is, it's on something that running out is considered to be a not good situation. There's a red band at the bottom, not one at the top.

CO2 fire-drench on a vessel or location, perhaps, where normal 'leisurely' pressure-testing wouldn't be possible and a slow CO2 leak might go un-noticed other than via the gauge?

[emeritus]

I had a look on one of the patent database sites for all published UK patents filed by Vickers Armstrongs : 429 in total. Nothing obviously relevant, apart from some relating to hydraulic seals. Prior to 1978, patents were only published if they were granted. If the patent application had been withdrawn or refused, it would not have been published. Another possibility was it could have been filed under a different name.

[MotorBikeLes]

Some years ago, I had some unknown (well, un-remembered now) burglar alarm. It had two sound sensors (ultra sonic) separated by a similar distance to those "loudspeaker like" enclosures. I set it up in our living room and played about trying to fool it, by moving very slowly. I rarely got very far. However, what I did notice was that any sort of a fire would set it off very easily. Use as a flame detector rather than a movement detector as suggested earlier could be the design consideration.
Les.

[Aaamusements]

The plot thickens... on opening it up yesterday I found that it contained 2 massive, leaky NiCad batteries and some circuitry, in the two front "speaker" holes are 1 x speaker and what looks like a microphone.

Incidentally the casing of both units seems to be quite good quality aluminium.

Any further ideas?