Damaged Air Tank

[pavman]

I have an old divers type air tank used to refill an air arms rifle, the shut off valve is damaged and can no longer operate. The bottle contains a charge of pressure, looking for ideas as to how to discharge the pressure and get the valve repaired?

 

pavman

[Axe]

Take it to a local dive shop, i'm sure they will be able to help you out.

 

Regards,

 

Axe.

[roblade]

how much test is left on it?

 

may be best to take it to the dive centre you have it filled at they are probably the best qualified to deal with this problem

 

DO NOT ATTEMPT TO REMOVE TO SERVICE IT YOURSELF!!! these cylinder contain up to 300bar and can ause seriouse daamage if anything goes pear shaped

 

ROB

[1 of 5]

Definately a job I'd be more than happy to pay someone-else to do given the risks of large explosions.

 

Have a peek here for that big bang feeling

[lurcherboy]

Ouch!!!!!!!!!!!!!!!!!!

[Axe]

Double ouch! I was brought up around these tanks, my father was a very keen diver. He taught me to be careful around the gear particularly the tanks. I've always appreciated the damage that one could cause but have never seen it. Ouch!

 

Regards,

 

Axe.

[SNAKEBITE]

I take it you are not going to buy a new one then throw the old one on the bonfire?

[pavman]

Bonfire, theres an idea!

 

I have found a local dive shop and they said bring it in, sound advice of which I will follow.

 

pavman

[Evilv]

What's wrong with a stirrup pump then? No need to pay £600 a year for that pass to the local gym, either, beats those rowing machines hands down.

 

[pavman]

guys,

 

The tank is now ok, it cost £100 in total, that inc drill out old bushing in valve to release pressure, re test and fit new valve and fill. The test is good for 2 years.

 

It would have cost £30 to scrap as it would need to be cut into 3 bits to ensure it could not be used again.

 

pavman

[SNAKEBITE]

What's wrong with a stirrup pump then? No need to pay £600 a year for that pass to the local gym, either, beats those rowing machines hands down.

 

:yp:

I hear moisture is the downfall with pumps.

 

WHAT DAMAGE CAN BE DONE AND HOW LONG DOES IT TAKE TO OCCOUR IF YOU USE A PUMP?

[SNAKEBITE]

It would have cost £30 to scrap as it would need to be cut into 3 bits to ensure it could not be used again.

That seems a bit steep!

Still at least you didn't just dump it in a lay-by. It might have clashed with the new indigneous species "fridge tree" or "washing machine bush"

[Axe]

What's wrong with a stirrup pump then? No need to pay £600 a year for that pass to the local gym, either, beats those rowing machines hands down.

 

I hear moisture is the downfall with pumps.

 

WHAT DAMAGE CAN BE DONE AND HOW LONG DOES IT TAKE TO OCCOUR IF YOU USE A PUMP?

The problem with styrup pumps is that they tend to create moisture from thge heat in the transfer valves etc. This can be over come by using a filter and allowing the heat to disapte when filling. That will also allow you to catch your breath. :yp:

 

As for the damage, well moisture will cause corrosion anywhere it reaches. Which inaffect is all the internals of a PCP. How long this takes depends on the usage and the number of times it is used. IF you fill correctly you shouldnt have too much trouble. Regualr servicing will avoid this too.

 

Axe.

Edited September 7, 2005 by Axe

[roblade]

The problem with styrup pumps is that they tend to create moisture from thge heat in the transfer valves etc. This can be over come by using a filter and allowing the heat to disapte when filling. That will also allow you to catch your breath. :yp:

 

As for the damage, well moisture will cause corrosion anywhere it reaches. Which inaffect is all the internals of a PCP. How long this takes depends on the usage and the number of times it is used. IF you fill correctly you shouldnt have too much trouble. Regualr servicing will avoid this too.

 

Axe.

axe you got the main ideas right just how it gets there worng LOL

 

the moisture comes from the air mositure content (humidity) and as the air is comressed to high pressure it condenses the moisture vapor to water and thats what causes the water to get inside the rifle. its not really anything to do with heat.

 

The filters you mention do take away a lot of this but i dont think any moisture trap will elliminate 100% water vapor.

 

now i would be the first to admit i could be totaly wrong about the above LOL

 

 

the best way to fill using a pump is to use the bleed vavle at least 3 times during a fill on a rifle, the more you use the vavle the better.

 

theres a lot to be said for pump, low maintencae low costs, very versatile, will never run out of and as long as you have your rifle fully serviced (not just seals) every couple of years will give you many years of good service.

 

Given a choice over a bottle or a pump i would have to say get a bottle if at all possible. But it is not always possible eg using public transport is not good when you have top lug a 23KG bottle about with you as well as all shooting gear. so you would have to have a think about would a pump or a bottle be best for you to get.

 

costs:bottle+ charge adaptor £200

refils (5 years 1 every two months) £150

retest (once 2.5 years) £60

petrol to dive shop £150

total cost for 5 years of use £560

 

pump £150

filters (x5 years) £150

total cost for 5 years £300

 

 

if your going to be choosing a bottle theres no two ways about it, it would have to be a 300bar bottle the larger the better. As there are a lot of rifle s out there now that are charged above 200 bar, so using a 232 bar bottle would probably give you 2 maybe 3 full charges to the rifle before you start filling below 200 bar wont make any difference to power just means you wont get so many shots out of it before needing to fill again.

 

ROB

 

PS snakebite as for what damage moisture can do once inside you rifle, just pop a steel washer into a glass of water for a few days to see for yourself, though i would have thought working in engineering you would have known what moisture can do to metal parts already.

Edited September 7, 2005 by roblade

[Axe]

As long as we reach the same point its all the same. I'm no expert Rob and accept the correction :yp: . Maybe a little of both as heat against cold metal will surely create condensation.

 

Axe.

 

PS Did ya get muh Ice Cream?

[Evilv]

I'm filling my new Axsor with a Hill's pump. I think I may have spotted a flash of water spray at the muzzle when firing the gun the other day. Does that sound reasonable? Is there any way 'dry' firing the thing might empty it of water? Maybe if I held it vertical so that water drained down to the firing valve and then let off a few 'dry' shots I might clear it out... What do you think chaps?

Edited September 7, 2005 by Evilv

[roblade]

I'm filling my new Axsor with a Hill's pump. I think I may have spotted a flash of water spray at the muzzle when firing the gun the other day. Does that sound reasonable?

 

Is there any way 'dry' firing the thing might empty it of water? Maybe if I held it vertical so that water drained down to the firing valve and then let off a few 'dry' shots I might clear it out... What do you think chaps?

the flash of water you think you saw is perfectly normal, I think you may even find thats its not water. I have seen this on rifles filled with bottles and pumps so nothing to worry about there.

 

as for trying to fire the water out of your rifle, i think the only way you can get rid of it once oits in is top strip the resevoir down and give it a good clean out, though this i would leave to a competant gunsmith if you do give it a go your self.....

 

MAKE SURE THE RESEVIOR IS EMPTY!!!!! DRY FIRE UNTIL EMPTY!!!

 

ROB :yp:

[SNAKEBITE]

PS snakebite as for what damage moisture can do once inside you rifle, just pop a steel washer into a glass of water for a few days to see for yourself, though i would have thought working in engineering you would have known what moisture can do to metal parts already.

I was aware that things would corode :yp: BUT I was wondering if the internals had been plated or some other means of protection used in anticipation of this problem.

Making the internals fron Stainless would eliminate this problem. Titanium would be better and then you can get into all the incalloys and exoctics but obviously costs would rocket.

[Evilv]

MAKE SURE THE RESEVIOR IS EMPTY!!!!! DRY FIRE UNTIL EMPTY!!!

 

ROB :yp:

 

 

 

Yes indeed....

 

Never attempt to open or fiddle with a CHARGED rifle or air tank...

 

BANG!!!!

 

Now shocked and blinded victim of traumatic amputation staggers away from his work bench with blood pouring from stumps of fingers and half empty eye sockets - well empty except for the strings of bloody nerve tissue dangling out onto his cheek.

 

My Axsor is pumped up to over one and a quarter tons per square inch.

 

An important reminder Rob - and thanks for the other info too.

Edited September 8, 2005 by Evilv

[Axe]

Tis very true indeed 2000psi is alot, but Evilv, did ya have to be so graphic! :yp:

 

Axe.

[SNAKEBITE]

eeerrrrrrr.......

 

For sale 1 AA410.

(No blood stains........ yet)

 

What the hell have I just bought? Maybe a hand grenade would have been safer! :yp:

[roblade]

I was aware that things would corode :yp: BUT I was wondering if the internals had been plated or some other means of protection used in anticipation of this problem.

Making the internals fron Stainless would eliminate this problem. Titanium would be better and then you can get into all the incalloys and exoctics but obviously costs would rocket.

stainless , not sure if this has been done but dont think i would be too happy lugging a 90% stainless action about for a couple of hours in the field. though think i might have heard about a stainless rifle somewhere.

 

Titanium, already been done, just have a think about the falcon Ti, am fairly certain that had a titanium resevoir on it.

 

as for all the others, i guess they do what they can, but even dive tanks corode eventualy so guess theres not a lot that can be done to stop it

 

ROB

[hawkeye]

I was aware that things would corode  :yp:  BUT I was wondering if the internals had been plated or some other means of protection used in anticipation of this problem.

Making the internals fron Stainless would eliminate this problem. Titanium would be better and then you can get into all the incalloys and exoctics but obviously costs would rocket.

stainless , not sure if this has been done but dont think i would be too happy lugging a 90% stainless action about for a couple of hours in the field. though think i might have heard about a stainless rifle somewhere.

 

Titanium, already been done, just have a think about the falcon Ti, am fairly certain that had a titanium resevoir on it.

 

as for all the others, i guess they do what they can, but even dive tanks corode eventualy so guess theres not a lot that can be done to stop it

 

ROB

You are correct ROB the falcon T-Bird has a titanium resevoir i have one thinking of getting rid, too many guns have to cut down.

[deadeye ive]

Are not Most Air gun resovoirs made from similar material to a modern shot gun barrel (Where it as to be Lightweight)with the internal surface plated to resist corrosion or in the case of a shot gun .....wear as well.Both senarios encounter high levels of stress :blink: or be it in different formats

One of the reasons PCP are so expensive is because they are built to allow for such Hazzards but as the regs which apply to having your divers bottle checked every 2 / 5 years there are no such regs with pcps but it's good advice to have the gun serviced by the maker as as been mentioned.

 

Let's take Air Arms for example ........it's commpany name and image are vital to its survival and futre prosperity and i imagine cleverer people than you and i design these guns with the idiots in mind .THEY CAN,T RISK THE SENARIO OF ONE EXPLODING!!!!!!!!!!!!!!!!!!Whilst being used in the correct manner.Imagine the publicity Maintaining the brand name is vital at all cost.

 

 

I know of no such incident where a PCP has exploded in the operators hands whilst it was being used correctly OR INCORRECTLEY.

 

 

Air Arms charged me £90 for my sevice.........Best money i've ever spent :o

 

 

Gas cylinders (Divers Bottles ) are drop forged .Their thick guage and heavy weight construction are there to withstand pressure but as for corrosion they have a certain shelf life ,HENCE The regs requiring you to have them checked.A recent photo on this forum indicates the consequences caused by ignorence.

 

Cheers Ive

 

No doubt from reading this response people will surf the web looking for a exploding PCP

[roblade]

I know of no such incident where a PCP has exploded in the operators hands whilst it was being used correctly OR INCORRECTLEY.

The only ocurance of this happening that i know of is when a theoben rapid was filled with a gas other than air. I know someone who has seen the pics of what happend but they are not available on the web.

 

But if anyone would like to see the rifle (or whats left of it), I have heard that Ben Taylor woudl welcome any one along to his shop to have a look at it.

 

NO AIR RIFLE SHOULD BE FILLED WITH ANY FORM OF GAS OTHER THAN THAT WHICH IT WAS DESINGED TO USE (usually air or Co2) Even a normaly inert gas can be dangerouse at high preasure levels!!!!

 

another accident waiting to happen, though again user error, is the theoben quick fill adaptors, fitted as after market mods to the base of the bottles!!!!!

 

As long as common sence prevails all airguns are safe, and if common sence fails........well theres always a darwin award available :blink:

 

ROB