Twin manifold plugs

[DavidFL]

If you have a tight fitting metal DIN plug and the valve is inadvertently opened, you will find it very hard to remove the plug. Not sure why anyone would use these, I thin that it's so you don't accidentally lose gas if the valve opens during transport, but I wouldn't do that.

When I first built my modern doubles, I was given two pieces of advice about the metal DIN plugs by local OC tech divers: (1) don't use them unless you have the tanks full of expensive helium mix and you are transporting them a long way, and, (2) invest in and carry a big wrench with a long handle because if they actually perform as designed (meaning roll on and some gas leakage) they are very difficult to remove.

 

[dogbone]

I was told by a tech diver that they often get put in to help protect the threads...he said something about if the tank gets knocked, it's easy for that part of the valve to deform...so you put a plug in to help keep that from happening...

 

[Marie13]

When I first built my modern doubles, I was given two pieces of advice about the metal DIN plugs by local OC tech divers: (1) don't use them unless you have the tanks full of expensive helium mix and you are transporting them a long way, and, (2) invest in and carry a big wrench with a long handle because if they actually perform as designed (meaning roll on and some gas leakage) they are very difficult to remove.

I had number 2 happen on a trip two years ago with a single tank. Good thing boat captain had the big wrench!

 

[rhwestfall]

I had number 2 happen on a trip two years ago

 

[rhwestfall]

Big wrench? Constipated?

 

[rhwestfall]

warh...

 

[Marie13]

 

[-JD-]

OP isn’t talking about those at all. He’s talking about the plugs in modular left/right valves that you remove in order to connect the manifold in the middle. If you remove the manifold, you then replace these plugs in the valves in order to use then as single valves. The below plugs go in the side, not where you connect a reg.

These are what he’s talking about.
DGX Modular Valve Port Plug, Notched (Reverse Threads) | Dive Gear Express®

Yep, got that. Should have mentioned it, true. The DIN plugs commentary roped me in ...

Other people are talking about DIN plugs, which are just dust caps to keep the din valve clean, and are NOT meant to be in place when the valve is open and there is no side manifold port. If you have a tight fitting metal DIN plug and the valve is inadvertently opened, you will find it very hard to remove the plug. Not sure why anyone would use these, I thin that it's so you don't accidentally lose gas if the valve opens during transport, but I wouldn't do that. And as has been mentioned upthread, a plastic plug can fail spectacularly in that situation.

ETA: Despite my comments in this thread - Retailers have specifically recommended that DIN sealing plugs should NOT be used on high F02 cylinders. See Twin manifold plugs

How about driving around with a cylinder of 100% in your trunk?

 

[Marie13]

Yep, got that. Should have mentioned it, true. The DIN plugs commentary roped me in ...


How about driving around with a cylinder of 100% in your trunk?

I’ve seen pics on FB where people had AL40 deco bottles upright in the back seat and strapped in with the seat belt.

 

[doctormike]

I


How about driving around with a cylinder of 100% in your trunk?

Good idea to secure it somehow. How does the DIN cap help with that?