I recently took my steel 72 2250 psi tank in to be filled. I had the tank hydro'd and vis done 11-06. I took it to a LDS that is closer to where I live.(Sports Chalet) They told me that it had the older style valve and burst disc and I had to change the valve. I purchased a Sherwood 5000 valve with a 3000 burst disc. On the box it says 2250 valve. Now they tell me I need to purchase a 2250 burst disc. Shouldn't they have sold me the proper valve with the proper burst disc to start with? After they took the old valve out they told me that the tank had to be tumbled, because it had a rust color inside. All this after 10 months of sitting in the closet and just used the tank for my wife to test her BC in the pool. I have looked at other 2250 tanks at another shop and they have 3000 burst disc's with the same Sherwood 5000 valve.
Burst disc
- Thread starter Skipper h
- Start date
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Scared Silly
Contributor
Well, I am not sure about what was old about the valve. Perhaps a J valve?? These are just fine if they have been maintained. Just keep the lever down. Burst disks should be replaced - I would have to double check on the reccomendation - IRCC after hydro. Who did the hydro/vis? if via a dive shop they should inspected the valve and burst disk as part of the requal.
If they are replacing the valve then they should have sold you the right valve with the right burst disk up front and not make you buy a second burst disk. They may have done this because burst disks should not be reused once removed from a valve. So they passed the cost on to you as it need to be switched (not cool).
Now the rust may be just a surface flash rust - common after a hydro if the water they used was cold and/or the cylinder was not drier fast enough. Depending on the amount and cylinder use (air only) it might or might not be okay.
Personally it sounds like someone who does not know what they are doing.
If they are replacing the valve then they should have sold you the right valve with the right burst disk up front and not make you buy a second burst disk. They may have done this because burst disks should not be reused once removed from a valve. So they passed the cost on to you as it need to be switched (not cool).
Now the rust may be just a surface flash rust - common after a hydro if the water they used was cold and/or the cylinder was not drier fast enough. Depending on the amount and cylinder use (air only) it might or might not be okay.
Personally it sounds like someone who does not know what they are doing.
francousteau
Contributor
The advice I was given was 1.7 X the working pressure. In your case 2250 X 1.7 = 3825, so a 4000psi burst disc would be the correct one.
Leadking
Contributor
The correct burst disc is 5/3 working pressure -10% +0% or 3750 psi.
As this tank is no longer made, no one makes a valve with the proper disc installed at the factory and the correct one must be installed at the dealer.
As this tank is no longer made, no one makes a valve with the proper disc installed at the factory and the correct one must be installed at the dealer.
Burst disks are labeled and packaged with the working pressure of the tank they are intended to be used with, not their burst pressure. The correct burst disk for a 2250psi tank is 2250psi. It will rupture at 3825psi (+/-).
DennisW
Contributor
If you had a J valve, there was nothing wrong with it. As a matter of fact, no matter what kind of valve you had, I would bet there was nothing wrong with it. I don't know the whole story, but I think I would find a new LDS.
francousteau
Contributor
Either I'm misunderstanding what you're saying here or you're wrong. For example, my 2 sets of twin Worthington 100's burst disks are stamped 5250psi (disks haven't been changed out yet) and the working pressure of the tanks are 3442. I also have on my shelf a brand new ThermoPro valve that has a stamp of 5250psi on the burst disk and it came new with a Worthington 100 @ 3442psi. I'd have to check my twin 80's, but I'm sure they have at least 4000 stamped on the disk. If you're just talking about packaging and not what is stamped on the disk, then I'm sure that you are correct.
I'm sure Lee can step in here to explain
Just an idea. How old is that steel tank? There used to be a valve that shot out a little slug, instead of having a burst assembly. These are no longer used due to safety issues. Take a look at that old valve, and that may be the answer.
The valve is not a J valve. . The tank was made in 1973 it was hydro'd in 1980 and I had it done 11-06. It's a Sherwood. Where the burst disc goes it looks like a flathead screw that has a hole in it. I went to a LDS that does Rebreather's and while I was there a guy came in that does hydro's. So I asked him about the rust and gave him the hydro date and where I took it, and he said that he did the Hydro on my tank and he put 3750 psi in the tank to do the hydro and the 3000 burst disc would be O.K. and that the rust inside was only flash rust and that I had nothing to worry about. As far as the burst disc goes I'm still a little confused. I have heard that the 3000 is O.K. but where I took the tank they refuse to fill the tank with a 3000 disc. They have already done the tumble so I'm stuck with that. And now I'm waiting for the tank the be shipped back to the shop. I talked to the store Manager and they are going to swap out the disc at no charge. For some reason I still feel that I got screwd. If the rust was O.K and all I needed to do was change the burst disc in the original valve then I would be looking at $6.00 for the disc plus the fill $5.00. Now I'm looking at $25.00 tumble $39.99 valve and fill $5.00 and a new visual $5.00 plus what ever else they might want to add on. Thanks for the input next time I will look for another DS. Skipper.
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