Swagelock QC6 source

[tbone1004]

@vioch interesting, I'll have to double check but the OD of the o-ring on the scuba regulators is .375". It's interesting that we don't use the normal external o-ring to seal with the scuba regulators and have gone to the internal seal. I'll see if our supply room has some of the tube adapters and check, if not I'll order one for shits and giggles. I wonder if they're buying the adapters from Tecme and Martin is machining them further from what Swagelok is selling.

I'll have the CAD drawings for SS-QC6-D-6ST shortly and will post them here to validate.

 

[lostsheep]

Subd.

I foresee the need for these soon; I wonder if I should fire up the CNC lathe or just throw money at the problem...

 

[rsingler]

At the risk of looking stupid, these DGX QD's are very inexpensive. And they're not suitable because of connection size, or what...? Don't know if their flow is a QC4 equivalent, or QC6.
Only $28. But no shutoff on the male side. Is that the problem?

 

[tbone1004]

@rsingler
couple reasons. Reason 1, they are very similar to the Omniswivel CEJN fittings and some of them are interchangeable. There was an issue a while ago where a variant got stuck and almost killed a cave diver. After that they went to QC6's.
Reason 2, no DESO and no way to purge. You have to have the female side on the whips and when unplugged they like to get grit and what not inside of them. The male side doesn't have a shutoff so there can be quite a bit of water pushed in when you connect them.

Those work really well for FFM's and some of us use them on the O2 side as well, but I wouldn't use it as a primary QD solution

 

[rsingler]

Is there an Omni DESO solution, or is Swagelok the only mfr worth dealing with?

 

[tbone1004]

Is there an Omni DESO solution, or is Swagelok the only mfr worth dealing with?

Omni does not. Swagelok has become the standard QD with CCR's in cave country so I wouldn't bother looking at other solutions. Are you getting on the vintage zoom tonight? We can talk about it more on that call, if not I need to call you about some Poseidon parts at some point anyway

 

[craig haymaker]

So apparently I am doing things backwards for connecting offboard into my Tec Se7en ! I am using the DGX "female" Hi flow QD on the offboard whip side and the mating "male" side with a check valve (pointing with the flow) on the system side. I figured that the 1- lb. opening pressure of the spring check would stop saltwater from passing into the system. But now after reading here, this idea sounds stupid ! Again I always thought that the female side of any QD would go on the supply side, as in the offboard whip ? I have got these DGX QDs through out my system : on the BOV, on each Tecme MAVs- inlet side, on the E-module's Dil and O2 connections and on my rich and lean offboard whips ! The "pressure (supply) side of all these QDs are the female QD and the downstream side are their mail counterparts !
My thinking was that with this configuration, I can go in lots of directions with the OB whip, if needed !
So exactly where would should I use these QC6 female and male QDs ?

 

[tbone1004]

So apparently I am doing things backwards for connecting offboard into my Tec Se7en ! I am using the DGX "female" Hi flow QD on the offboard whip side and the mating "male" side with a check valve (pointing with the flow) on the system side. I figured that the 1- lb. opening pressure of the spring check would stop saltwater from passing into the system. But now after reading here, this idea sounds stupid ! Again I always thought that the female side of any QD would go on the supply side, as in the offboard whip ? I have got these DGX QDs through out my system : on the BOV, on each Tecme MAVs- inlet side, on the E-module's Dil and O2 connections and on my rich and lean offboard whips ! The "pressure (supply) side of all these QDs are the female QD and the downstream side are their mail counterparts !
My thinking was that with this configuration, I can go in lots of directions with the OB whip, if needed !
So exactly where would should I use these QC6 female and male QDs ?

If you are using a non-DESO quick disconnect, which most of them are, then they are similar to a BC fitting where the female side is shut-off but the male side is not. If that is the case, then the female side must be on the supply side so when you disconnect it you don't blow gas everywhere.
The reason you have the check valve on the system is so the LP side doesn't depressurize when you disconnect it which is not ideal. The check valve will stop water entry so long as the system is pressurized, but it has to be pressurized.

The DGX style quick disconnects do let more water into the system than the QC6's so every time you disconnect in the water you are letting a volume of water roughly equivalent to the internal volume of the male nipple into the system. It's only a few drops, but it's more than nothing and I would make sure to pay extra attention to cleaning them. The QC6's let almost no water in when you connect which is nice.

What I do, and what many others do as well is use the smaller/cheaper CEJN/Omniswivel/DGX type disconnects on places that are not intended to be connected/disconnected regularly. FFM, BOV, etc. The QC6's are used on all of the tanks to plug into the "system".

 

[craig haymaker]

If you are using a non-DESO quick disconnect, which most of them are, then they are similar to a BC fitting where the female side is shut-off but the male side is not. If that is the case, then the female side must be on the supply side so when you disconnect it you don't blow gas everywhere.
The reason you have the check valve on the system is so the LP side doesn't depressurize when you disconnect it which is not ideal. The check valve will stop water entry so long as the system is pressurized, but it has to be pressurized.

The DGX style quick disconnects do let more water into the system than the QC6's so every time you disconnect in the water you are letting a volume of water roughly equivalent to the internal volume of the male nipple into the system. It's only a few drops, but it's more than nothing and I would make sure to pay extra attention to cleaning them. The QC6's let almost no water in when you connect which is nice.

What I do, and what many others do as well is use the smaller/cheaper CEJN/Omniswivel/DGX type disconnects on places that are not intended to be connected/disconnected regularly. FFM, BOV, etc. The QC6's are used on all of the tanks to plug into the "system".

Thank you tbone 1004. So I have the SS-QC6- D-4PF on the male side. I guess that this has a valve, and connecting it - opens the valve ! So it won’t blow gas if disconnected, right? So re-install them, but flip them around with the male stem on my BO regulators, correct ?

 

[tbone1004]

Thank you tbone 1004. So I have the SS-QC6- D-4PF on the male side. I guess that this has a valve, and connecting it - opens the valve ! So it won’t blow gas if disconnected, right? So re-install them, but flip them around with the male stem on my BO regulators, correct ?

yes, if you push on the tip of the connector it will open the valve and release gas, it's an upstream valve and is quite difficult to connect at 100m, but still possible.
If using QC6's, the "standard" has the stems on the supply, bodies on the receiving side.