Have you done this yourself or been there when they have done it?
Din Plugs
- Thread starter mad1
- Start date
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But it looks like it depends...there are the holes on my Halcyon (when I had a first stage o-ring fail it bubbled through there), but I didn't see them on my Sea Elite (300 bar) or on the OMS valve on my 40 (200 bar).Padipro once bubbled...
IF, the plug was seated and IF the valve wasn't drilled with a vent port the plug is only made of a soft plastic, they do cross thread easily, so I'm not saying that it deffinately would blow out ripping the threads off the plug killing someone but the possibility is there for something bad to happen. And as for that tiny bit of air between the plug and the valve, there's a whole lot of air between the plug and the valve when you open the valve and if the valve is opened during the drive to the dive site there would be a whole lot of air behind that plastic plug for quite some time.
Besides James you're a fellow Deltoid, you're supposed to agree with me.So when are you coming down to do the Grove? I'm itchen to do it again.
Scott
I can't imagine that anyone would be able to get that thing off with 3000+ psi sitting behind it no matter what type of wrench was used....but I am with you guys in not wanting to be near it when it was attempted.
Wrongkey and UP:
RE: removing the SS plugs from Gulftex is cake with a big wrench. I have 11 of them personally and have been using them for about 5 years. They are worth every penny. When the truck is tightly packed, and all the doubles have trimix in them, things sometimes shift and bump the valves on, if you are using these plugs you dont end up with any nasty (and expensive) surprises when you get ready to dive.
RE: removing the SS plugs from Gulftex is cake with a big wrench. I have 11 of them personally and have been using them for about 5 years. They are worth every penny. When the truck is tightly packed, and all the doubles have trimix in them, things sometimes shift and bump the valves on, if you are using these plugs you dont end up with any nasty (and expensive) surprises when you get ready to dive.
..even with a Florida fill you can still get those puppies off if the valve has been opened? I realized after looking at them that the manifold hole is irrelevant since the plugs use a captured o-ring and wouldn't vent the pressure unless the o-ring burst.
no problem getting them off at all. usually only takes 3 to 4 turns with the wrench and then the gas will vent and you can finish turning by hand.
for the confirmation
My friend saw a "plastic" plug go through a wall (two sheets of sheetrock) when someone cranked open a valve while the plug was still in place. Gas delivery rate is so high, so quickly (even more so with the 1.5 turn valves that are coming out now) that a plastic plug can hold the pressure back to the point that it'll just extrude with one heck of a lot of force.
I've stopped using the plastic plugs for now, and I'm wavering between going the metal or just a protective sleeve route.
Roak
I am the U.S. manufacturer of the Stainless Steel DIN plugs referenced in this thread. The product was designed for one primary purpose and that is to "prevent the loss of gas during transport due to an accidental valve opening". An additional benefit of this product is in protecting the valve orifice from impact damage.
These plugs are made of solid 316 stainless steel and are much stronger than the connector found on a first stage. They will not "fly out" of the valve when pressurized any more than your first-stage (regulator) will "fly out" when pressurized.
With regards to their removal upon accidental (or intentional) pressurization, they are easily removed with an 8" adjustable (crescent) wrench. One needs only to 1)turn off the valve, 2)unscrew the plug 1 - 2 turns (until the small amount of trapped gas escapes), and then 3)remove the plug by hand. It's been done hundreds and hundreds of times without incident nor thread damage (you may occasionally have to replace the (standard-sized) o-ring.
For those remaining doubters I will add the following post from the Techdiver archives originally published in 2001. Feel free to ask any questions you may have. And thanks for allowing me to respond.
Chuck Noe
The 316 stainless these plugs are made of have a tensile strength of
95,000 psi. The shear strength is easily in excess of 50,000 psi. So
let's talk about the tank valves (which are made of brass).
Typical naval brass has a shear strength of somewhere in the
neighborhood of 44,000 psi. The surface area of the plugs (which are
holding in the tank pressure) is approximately .622 square inches which
means that a tank filled to a pressure of 3,600 psi (heaven forbid)
would be applying an outward force on the plug of around 2,239 pounds.
EVEN IF YOU ONLY FULLY ENGAGED ONE THREAD of the plug into the valve
opening, the contact surface area of the SINGLE THREAD would be
somewhere around .1847 square inches. Even if the force of the
compressed gas were applied perpendicularly (which it's not), the
material would theoretically withstand over 8,125 pounds of force. This
amounts to a safety factor of (8,125/2,239 =) 3.63 times the actual
force applied (WITH ONLY ONE THREAD ENGAGED!). With all 8 threads
engaged you're looking at a safety factor of 29 TIMES!
Now keep in mind that the seal is created by an o-ring and once the plug
is backed out about one and a half turns, the gas which is captured
escapes past the seal and then past the threads. Even when used in 200
BAR valves, there remains plenty of threading to withstand the force
pushing against the plug while venting it.
Now for those of you who may argue that the plug won't unscrew with the
pressure trapped inside, testing reveals that it takes no more than 15
ft/lbs of torque to remove the plug from a 300 BAR DIN valve (a dirty
one at that) when it has been pressurized to 3,600 psi. Try it if you
don't believe me.
These plugs are made of solid 316 stainless steel and are much stronger than the connector found on a first stage. They will not "fly out" of the valve when pressurized any more than your first-stage (regulator) will "fly out" when pressurized.
With regards to their removal upon accidental (or intentional) pressurization, they are easily removed with an 8" adjustable (crescent) wrench. One needs only to 1)turn off the valve, 2)unscrew the plug 1 - 2 turns (until the small amount of trapped gas escapes), and then 3)remove the plug by hand. It's been done hundreds and hundreds of times without incident nor thread damage (you may occasionally have to replace the (standard-sized) o-ring.
For those remaining doubters I will add the following post from the Techdiver archives originally published in 2001. Feel free to ask any questions you may have. And thanks for allowing me to respond.
Chuck Noe
The 316 stainless these plugs are made of have a tensile strength of
95,000 psi. The shear strength is easily in excess of 50,000 psi. So
let's talk about the tank valves (which are made of brass).
Typical naval brass has a shear strength of somewhere in the
neighborhood of 44,000 psi. The surface area of the plugs (which are
holding in the tank pressure) is approximately .622 square inches which
means that a tank filled to a pressure of 3,600 psi (heaven forbid)
would be applying an outward force on the plug of around 2,239 pounds.
EVEN IF YOU ONLY FULLY ENGAGED ONE THREAD of the plug into the valve
opening, the contact surface area of the SINGLE THREAD would be
somewhere around .1847 square inches. Even if the force of the
compressed gas were applied perpendicularly (which it's not), the
material would theoretically withstand over 8,125 pounds of force. This
amounts to a safety factor of (8,125/2,239 =) 3.63 times the actual
force applied (WITH ONLY ONE THREAD ENGAGED!). With all 8 threads
engaged you're looking at a safety factor of 29 TIMES!
Now keep in mind that the seal is created by an o-ring and once the plug
is backed out about one and a half turns, the gas which is captured
escapes past the seal and then past the threads. Even when used in 200
BAR valves, there remains plenty of threading to withstand the force
pushing against the plug while venting it.
Now for those of you who may argue that the plug won't unscrew with the
pressure trapped inside, testing reveals that it takes no more than 15
ft/lbs of torque to remove the plug from a 300 BAR DIN valve (a dirty
one at that) when it has been pressurized to 3,600 psi. Try it if you
don't believe me.
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