CO2 cylinder- teflon tape the threads?

Gary Majchrzak · 04/17/2006, 03:43 PM

My CO2 regulator instructions say to teflon tape the threads before attaching the regulator to the CO2 cylinder.
The employee at the store where I refill the cylinder with CO2 says I shouldn't tape the threads.
What do you do?

MCary · 04/17/2006, 03:46 PM

If you have a properly seated plastic gasket you should not have to tape the threads. The threads would not be exposed to the gas.

Gary Majchrzak · 04/17/2006, 03:50 PM

Quote:

Originally posted by MCary
If you have a properly seated plastic gasket you should not have to tape the threads. The threads would not be exposed to the gas.

The regulator instructions also say to place the O-ring between the regulator and the tank.
The LGS (local gas store) employee agrees with these instructions regarding the O-ring, but not about the tape...

glaudds · 04/17/2006, 04:14 PM

Quote:

Originally posted by Gary Majchrzak
The regulator instructions also say to place the O-ring between the regulator and the tank.
The LGS (local gas store) employee agrees with these instructions regarding the O-ring, but not about the tape...

No teflon tape here. I have a special fitting with an o ring that sits flush into the flat surface of the regulator. That's where the seal is.
Prior to having this fitting, I would change the washer between the tank and regulator everytime I refilled the tank.

Paintbug · 04/17/2006, 04:23 PM

the place you get your tanks filled should have some plastic gaskets that are intended for that use. teflon tape gets messy for those who fill the tanks. thats why they dont want you using it.

MCary · 04/17/2006, 04:24 PM

Like I said, there should be no exposure from the gas on the threads. The threads are just to keep the gas line from the tank connected to the gas line on the regulator. The gap between the 2 is sealed with an o-ring or a plastic gasket. Compare this with plumbing that requires teflon tape. In many cases the end of the male thread makes contact directly with the gas or fluid being transported via the pipe.

Mike

Amphiprion · 04/17/2006, 04:33 PM

The teflon tape is a good safeguard. You should make it as redundant as possible when dealing with a gas. If there is an irregularity in the O-ring, the tape will help keep the gas from leaking.

Ewan · 04/17/2006, 04:48 PM

Teflon tape is not meant to be used with compressed gas. The theory is that small pieces can break free (and DO while tightening the threaded fitting) and become lodged in the regulator. There are specific plastic rings that are meant to be seated in the female portion of the regulator, and then the regulator is tightened with a correct-sized spanner. The plastic ring allows you to tighten the fitting down properly, and upon compression, provides a leak-free seal.

Ask anyone who deals with compressed gas for a living, and I'm certain they'll tell you the same.

With the correct gaskets (and appropriate spanner), there is no leak.
-E.

Mr. Ugly · 04/17/2006, 04:52 PM

Do not tape threads. Tape shreds can get into the regulator and cause it to fail. At best you lose all your CO2, at worse you lose all your CO2 in a regulator explosion that severely injures you.

Do a Google on:

"compressed gas safety"
"pressure regulator" failure
"pressure regulator" injury accident

Here's some useful info:

http://www.scottecatalog.com/ScottTe...c?OpenDocument

http://www.scottecatalog.com/DSGuide...0?OpenDocument

http://www.matheson-trigas.com/mathp...ed%20Gases.pdf

Mr. Ugly · 04/17/2006, 05:11 PM

BTW, somewhere in my recent Googling, I ran across an article about a woman who had a regulator blow up in her face resulting in a broken jaw. That particular incident was not due to teflon, but it does give you an idea about the energies involved.

goda · 04/17/2006, 05:43 PM

Quote:

Originally posted by Mr. Ugly
BTW, somewhere in my recent Googling, I ran across an article about a woman who had a regulator blow up in her face resulting in a broken jaw. That particular incident was not due to teflon, but it does give you an idea about the energies involved.

it had to of been her fault or a really old / cheep reg

usualy most accidents happen during filling or more likely during the hydro that you are suppose to have done every 5 years

if your worried about somthing like this happening it wont. worst not usuing somthing to seal a tank can do is cause a leak.

AZDesertRat · 04/17/2006, 06:40 PM

Tape on the threads won't serve any purpose. The sealing surface is the flat face flange between the regulator and the bottle. Besides the theads aren't a tapered pipe thread they are more like a straight bolt thread.

Amphiprion · 04/17/2006, 07:13 PM

All aquarium-grade manufacturers (i.e. regulators intended for non hydrocarbon gases) recommend the use of teflon tape to ensure that no gas escapes.

Ewan · 04/17/2006, 07:21 PM

Quote:

Originally posted by Amphiprion
All aquarium-grade manufacturers (i.e. regulators intended for non hydrocarbon gases) recommend the use of teflon tape to ensure that no gas escapes.

With exception of 2 that I own.

1. Aquamedic
2. JBJ

They both came with instructions, and both said not to use thread tape.

geo · 04/17/2006, 07:33 PM

Quote:

Originally posted by AZDesertRat
Tape on the threads won't serve any purpose. The sealing surface is the flat face flange between the regulator and the bottle. Besides the theads aren't a tapered pipe thread they are more like a straight bolt thread.

This is absolutely correct. If the gasket were not to seal the tape would not keep it from leaking.

Amphiprion · 04/17/2006, 07:34 PM

I also have an Aquamedic, and nowhere in the instructions does it say not to use the tape. In fact, it never even mentions it. I don't have a JBJ, so I cannot speak for them (I was unaware that they sold regulators). Also, the Milwaukee regulators do recommend the use of tape, or (quote) "you will lose gas." I don't know for sure, but there may be a large disparity in workmanship that would warrant such differences. I used it on my aquamedic regulator as a precaution and I have never had a problem with either regulators in the years that I have used them.

geo · 04/17/2006, 07:41 PM

The nut on a regulator is loose, there is metal to metal contact on the side opposite of the gasket. If the gasket does not seal the tape on the threads serve no purpose. Even if the tape sealed the thread connection gas would leak from the back of the nut.

Amphiprion · 04/17/2006, 07:44 PM

True, but it does not account for thread irregularities that the tape could possibly prevent. Like I said before, it may not be necessary, but I like redundancy when dealing with gases.

Ewan · 04/17/2006, 08:03 PM

Quote:

Originally posted by Amphiprion
I also have an Aquamedic, and nowhere in the instructions does it say not to use the tape. In fact, it never even mentions it. I don't have a JBJ, so I cannot speak for them (I was unaware that they sold regulators). Also, the Milwaukee regulators do recommend the use of tape, or (quote) "you will lose gas." I don't know for sure, but there may be a large disparity in workmanship that would warrant such differences. I used it on my aquamedic regulator as a precaution and I have never had a problem with either regulators in the years that I have used them.

You're right... the aquamedic doesn't mention teflon tape at all in the instructions. I just checked it out myself.

Mr. Ugly · 04/17/2006, 08:14 PM

Compressed Gas Association (CGA) defines the safety standards for working with compressed gases and associated equipment. Reputable safety documentation typically references CGA.

I recall seeing one manufacturer recommend teflon for their regulator, but most likely that was some employee's "common sense" recommendation, and not anything from CGA.

More info:

http://www.scottecatalog.com/ScottTe...5?OpenDocument

Pertinent section states:

"Valve Outlet Connections and Fittings: Be sure all fittings and connection threads meet properly - never force. Dedicate your regulator to a single valve connection even if it is designed for different gases. NEVER cross thread or use adapters between nonmating equipment and gas cylinders. Most valve outlet connections are designed with metal-to-metal seals; use washers only if indicated. Do not use TeflonÃ‚Â® tape on the valve threads to prevent leaking, it may become powdered and get caught on the regulator poppet causing full pressure downstream. Never use pipe dope on pipe threads. Also, never turn the threads the wrong way. This may produce brass particles that might get caught in the regulatorÃ¢â‚¬â„¢s poppet."

People make a lot of assumptions and overlook a lot of things with regard to compressed gas safety. I reviewed this recently with several people who should have known better, and they were very surprised when I gave them the urls in these posts. They only had been working with compressed gases for the last 30 years. It probably had been a while since they last had RTFM.

Mr. Ugly · 04/17/2006, 08:17 PM

Just because Aquamedic doesn't point out the danger of using teflon, doesn't mean that you should use it. Industry standard supercedes Aquamedic.

I don't have the reference handy, but there is one that explains that teflon on the straight threads of CGA fittings, as on regulators, can actually cause the threads to deform and leak over time.

Amphiprion · 04/17/2006, 09:21 PM

There is a lot of conflicting information, but I checked out some American Chemical Society info (on different gas usages) and they say not to use it. I trust the ACS, but I wonder why manufacturers recommend using it in their instruction manuals, websites, etc. When I get my next fill up, I suppose I won't be using it any more.

suasponte2/75 · 04/18/2006, 12:16 AM

If people are worried about leaks, why not do a soap test after securing the regulator and opening up the valve? Since the teflon is just a safety for leaks you can probably be rest assured about any leaks after the soap test. Similiar to what most people should be doing when they hook up their gas grills. Am I missing something?

Minh

Mr. Ugly · 04/18/2006, 12:46 AM

Minh, you are absolutely correct.

Leak test is recommended safe practice for working with compressed gases.

Mr. Ugly · 04/18/2006, 01:03 AM

Quote:

Originally posted by Amphiprion
I trust the ACS, but I wonder why manufacturers recommend using it in their instruction manuals, websites, etc.

Probably because they didn't RTFM, and it does seem to make sense at first.

ACS, Prudent Practices, CGA all know how to keep scientists from blowing themselves up. Or at least make it harder for them to do so

Another no-no is teflon on gas piping. So for the DIY folks out there... don't use teflon on the gas connections for your furnace, for example. Same thing about the teflon getting into the regulator or control devices and causing leaks leading to fires and/or explosions.

View Poll Results: tape the threads?
tape the threads	10	43.48%
do NOT tape the threads	13	56.52%
Voters: 23. You may not vote on this poll

04/17/2006, 03:43 PM	#1
Gary Majchrzak Team RC Member Join Date: Nov 2001 Location: Rochester, NY Posts: 41,560	CO2 cylinder- teflon tape the threads? My CO2 regulator instructions say to teflon tape the threads before attaching the regulator to the CO2 cylinder. The employee at the store where I refill the cylinder with CO2 says I shouldn't tape the threads. What do you do? __________________ over 24 years experience with multiple types of marine aquarium systems see Upstate Reef Society Forum on RC and FB GOOGLE JUNIOR'S REEF Current Tank Info: 84x24x30 265g reef past TOTM honors

04/17/2006, 04:23 PM	#5
Paintbug Registered Member Join Date: Mar 2005 Location: Stoneville, NC Posts: 6,169	the place you get your tanks filled should have some plastic gaskets that are intended for that use. teflon tape gets messy for those who fill the tanks. thats why they dont want you using it. __________________ Never ask a girl over to see your crabs!! <-Tony-> Current Tank Info: NONE currently

04/17/2006, 04:33 PM	#7
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	The teflon tape is a good safeguard. You should make it as redundant as possible when dealing with a gas. If there is an irregularity in the O-ring, the tape will help keep the gas from leaking. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

04/17/2006, 07:13 PM	#13
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	All aquarium-grade manufacturers (i.e. regulators intended for non hydrocarbon gases) recommend the use of teflon tape to ensure that no gas escapes. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

04/17/2006, 03:46 PM	#2
MCary Premium Member Join Date: Dec 2002 Location: Hardin, Montana Posts: 3,142	If you have a properly seated plastic gasket you should not have to tape the threads. The threads would not be exposed to the gas.

04/17/2006, 04:24 PM	#6
MCary Premium Member Join Date: Dec 2002 Location: Hardin, Montana Posts: 3,142	Like I said, there should be no exposure from the gas on the threads. The threads are just to keep the gas line from the tank connected to the gas line on the regulator. The gap between the 2 is sealed with an o-ring or a plastic gasket. Compare this with plumbing that requires teflon tape. In many cases the end of the male thread makes contact directly with the gas or fluid being transported via the pipe. Mike

04/17/2006, 04:48 PM	#8
Ewan Premium Member Join Date: Oct 1999 Location: Fredericton, NB, Canada Posts: 2,594	Teflon tape is not meant to be used with compressed gas. The theory is that small pieces can break free (and DO while tightening the threaded fitting) and become lodged in the regulator. There are specific plastic rings that are meant to be seated in the female portion of the regulator, and then the regulator is tightened with a correct-sized spanner. The plastic ring allows you to tighten the fitting down properly, and upon compression, provides a leak-free seal. Ask anyone who deals with compressed gas for a living, and I'm certain they'll tell you the same. With the correct gaskets (and appropriate spanner), there is no leak. -E.

04/17/2006, 04:52 PM	#9
Mr. Ugly Registered Member Join Date: Jan 2005 Location: CA Posts: 3,159	Do not tape threads. Tape shreds can get into the regulator and cause it to fail. At best you lose all your CO2, at worse you lose all your CO2 in a regulator explosion that severely injures you. Do a Google on: "compressed gas safety" "pressure regulator" failure "pressure regulator" injury accident Here's some useful info: http://www.scottecatalog.com/ScottTe...c?OpenDocument http://www.scottecatalog.com/DSGuide...0?OpenDocument http://www.matheson-trigas.com/mathp...ed%20Gases.pdf

04/17/2006, 05:11 PM	#10
Mr. Ugly Registered Member Join Date: Jan 2005 Location: CA Posts: 3,159	BTW, somewhere in my recent Googling, I ran across an article about a woman who had a regulator blow up in her face resulting in a broken jaw. That particular incident was not due to teflon, but it does give you an idea about the energies involved.

04/17/2006, 06:40 PM	#12
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Tape on the threads won't serve any purpose. The sealing surface is the flat face flange between the regulator and the bottle. Besides the theads aren't a tapered pipe thread they are more like a straight bolt thread.

04/17/2006, 07:34 PM	#16
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	I also have an Aquamedic, and nowhere in the instructions does it say not to use the tape. In fact, it never even mentions it. I don't have a JBJ, so I cannot speak for them (I was unaware that they sold regulators). Also, the Milwaukee regulators do recommend the use of tape, or (quote) "you will lose gas." I don't know for sure, but there may be a large disparity in workmanship that would warrant such differences. I used it on my aquamedic regulator as a precaution and I have never had a problem with either regulators in the years that I have used them. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

04/17/2006, 07:41 PM	#17
geo RC Mod Join Date: Apr 2000 Location: St. George Island, FL Posts: 19,512	The nut on a regulator is loose, there is metal to metal contact on the side opposite of the gasket. If the gasket does not seal the tape on the threads serve no purpose. Even if the tape sealed the thread connection gas would leak from the back of the nut. __________________ I'm sorry I had a fight in the middle of your Black Panther party.

04/17/2006, 07:44 PM	#18
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	True, but it does not account for thread irregularities that the tape could possibly prevent. Like I said before, it may not be necessary, but I like redundancy when dealing with gases. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

04/17/2006, 08:14 PM	#20
Mr. Ugly Registered Member Join Date: Jan 2005 Location: CA Posts: 3,159	Compressed Gas Association (CGA) defines the safety standards for working with compressed gases and associated equipment. Reputable safety documentation typically references CGA. I recall seeing one manufacturer recommend teflon for their regulator, but most likely that was some employee's "common sense" recommendation, and not anything from CGA. More info: http://www.scottecatalog.com/ScottTe...5?OpenDocument Pertinent section states: "Valve Outlet Connections and Fittings: Be sure all fittings and connection threads meet properly - never force. Dedicate your regulator to a single valve connection even if it is designed for different gases. NEVER cross thread or use adapters between nonmating equipment and gas cylinders. Most valve outlet connections are designed with metal-to-metal seals; use washers only if indicated. Do not use TeflonÃ‚Â® tape on the valve threads to prevent leaking, it may become powdered and get caught on the regulator poppet causing full pressure downstream. Never use pipe dope on pipe threads. Also, never turn the threads the wrong way. This may produce brass particles that might get caught in the regulatorÃ¢â‚¬â„¢s poppet." People make a lot of assumptions and overlook a lot of things with regard to compressed gas safety. I reviewed this recently with several people who should have known better, and they were very surprised when I gave them the urls in these posts. They only had been working with compressed gases for the last 30 years. It probably had been a while since they last had RTFM.

04/17/2006, 08:17 PM	#21
Mr. Ugly Registered Member Join Date: Jan 2005 Location: CA Posts: 3,159	Just because Aquamedic doesn't point out the danger of using teflon, doesn't mean that you should use it. Industry standard supercedes Aquamedic. I don't have the reference handy, but there is one that explains that teflon on the straight threads of CGA fittings, as on regulators, can actually cause the threads to deform and leak over time.

04/17/2006, 09:21 PM	#22
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	There is a lot of conflicting information, but I checked out some American Chemical Society info (on different gas usages) and they say not to use it. I trust the ACS, but I wonder why manufacturers recommend using it in their instruction manuals, websites, etc. When I get my next fill up, I suppose I won't be using it any more. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

04/18/2006, 12:16 AM	#23
suasponte2/75 Premium Member Join Date: Jun 2002 Location: The Bay Area (Fremont, CA) Posts: 514	If people are worried about leaks, why not do a soap test after securing the regulator and opening up the valve? Since the teflon is just a safety for leaks you can probably be rest assured about any leaks after the soap test. Similiar to what most people should be doing when they hook up their gas grills. Am I missing something? Minh

04/18/2006, 12:46 AM	#24
Mr. Ugly Registered Member Join Date: Jan 2005 Location: CA Posts: 3,159	Minh, you are absolutely correct. Leak test is recommended safe practice for working with compressed gases.