Robert E Lee Posted September 8, 2011 Report Posted September 8, 2011 Observed this "tee" on a propane gas line at one of today's inspections, sure looks like a soldered joint to me. I know gas lines are supposed to be welded or brazed, what are the ramifications of a soldered fitting? Click to Enlarge 39.89 KB
Jim Katen Posted September 8, 2011 Report Posted September 8, 2011 Observed this "tee" on a propane gas line at one of today's inspections, sure looks like a soldered joint to me. I know gas lines are supposed to be welded or brazed, what are the ramifications of a soldered fitting? The solder joint is more likely to leak than a brazed joint. Otherwise, I don't know of any ramifications.
Tom Raymond Posted September 8, 2011 Report Posted September 8, 2011 Why would that be, especially at the low pressures of gas?
Les Posted September 8, 2011 Report Posted September 8, 2011 Brazing and soldering are different processes. One combines metal and the other provides a seal between metals. I am sure there is a paper out there that discusses the positives of mechanical fastening (thread and socket, flare, compression, etc) versus solder and braze. Maybe expansion and contraction, transmission movements etc are considerations. Don't have the code reference nor the aga reference with me on the road today.
Jim Katen Posted September 8, 2011 Report Posted September 8, 2011 Why would that be, especially at the low pressures of gas? The pressure wouldn't cause it to leak, but smacking it with your foot might.
rkenney Posted September 8, 2011 Report Posted September 8, 2011 G2414.10.2 (403.10.2) Tubing joints. Tubing joints shall be made with approved gas tubing fittings or be brazed with a material having a melting point in excess of 1,000ºF (538ºC) or made with press-connect fittings complying with ANSI LC-4. Brazing alloys shall not contain more than 0.05-percent phosphorus. Doesn't say why. Joints that melt at low temperatures could be it though.
Tom Raymond Posted September 8, 2011 Report Posted September 8, 2011 So the leak is the result of a weaker mechanical connection, that makes perfect sense. With modern solder alloys melting anywhere between 244 and 530 F, it clearly shouldn't have been soldered anyways. I rarely see copper gas lines here.
Greg Booth Posted September 8, 2011 Report Posted September 8, 2011 Propane systems in my region are nearly always copper......... if the installation is done by the gas supplier. Natural is always black pipe.[] ............Greg
John Kogel Posted September 9, 2011 Report Posted September 9, 2011 G2414.10.2 (403.10.2) Tubing joints. Tubing joints shall be made with approved gas tubing fittings or be brazed with a material having a melting point in excess of 1,000ºF (538ºC) or made with press-connect fittings complying with ANSI LC-4. Brazing alloys shall not contain more than 0.05-percent phosphorus. Doesn't say why. Joints that melt at low temperatures could be it though. Brazing is simply stronger than soldering, so less likely to be knocked apart, what Jim said.For example, when I was a kid, I brought my bike to the local shop for a frame repair, and the old guy brazed it with an acetylene torch and a brass rod. We would have laughed if he'd just soldered it.
Chad Fabry Posted September 9, 2011 Report Posted September 9, 2011 Brazing and soldering are different processes. One combines metal and the other provides a seal between metals. I'm not sure what you mean, Les. Brazing and soldering create the same type of connection but use different connectors. Brazing "sticks" the rod to the object through capillary action just as soldering sticks the rod or fills a gap. When one brazes no metals are combined like they are in a welded joint. FTR, most brazing rods are alloys of copper and zinc, not brass. The connections produced through brazing are frequently stronger than the brazed material and compared to a soldered joint, the fire resistance is undeniable.
Les Posted September 9, 2011 Report Posted September 9, 2011 Brazing and soldering are different processes. One combines metal and the other provides a seal between metals. I'm not sure what you mean, Les. Brazing and soldering create the same type of connection but use different connectors. Brazing "sticks" the rod to the object through capillary action just as soldering sticks the rod or fills a gap. When one brazes no metals are combined like they are in a welded joint. FTR, most brazing rods are alloys of copper and zinc, not brass. The connections produced through brazing are frequently stronger than the brazed material and compared to a soldered joint, the fire resistance is undeniable. Chad, you made me go and learn something! I mostly agree with your general statement, but now learn there are definitive terms for brazing and soldering. I generally think of brazing as braze welding and not braze soldering, as in hvac. Maybe it was my "farm" background. We often fixed a part on farm machinery by brazing; could be done in the field away from electricity. We were, as I now learn, actually braze welding! I was fully aware of the temps, but not the definitive temps for terminology. I hate to learn in a public forum!
gtblum Posted September 9, 2011 Report Posted September 9, 2011 Propane systems in my region are nearly always copper......... if the installation is done by the gas supplier. Natural is always black pipe.[] ............Greg Slight drift. (haha) Greg, are you writing in from a house boat? Sounds pretty bad down your way.
kurt Posted September 9, 2011 Report Posted September 9, 2011 I have never, ever seen a soldered gas line. I've been operating under a folklore for the last 30 years that doesn't allow soldered gas lines. I have no basis for that lore other than everyone I know believes it. I think we are basing our ignorance in the idea that someone might put a torch on it.
John Kogel Posted September 9, 2011 Report Posted September 9, 2011 I have never, ever seen a soldered gas line. I've been operating under a folklore for the last 30 years that doesn't allow soldered gas lines. I have no basis for that lore other than everyone I know believes it. I think we are basing our ignorance in the idea that someone might put a torch on it. This copper gas line is just glued together with paint. []I have pics of unpainted pipe joints, but they are buried. We see lots of soft copper gas lines, steel is usually a short trunk off the meter. Click to Enlarge 37.72 KB
kurt Posted September 9, 2011 Report Posted September 9, 2011 I'll rephrase that...... I've never seen rigid copper gas lines. I've seen plenty of soft flex copper gas lines. It just doesn't seem smart to have brazed gas lines in a house; some nut might try to work on it.
John Dirks Jr Posted September 9, 2011 Report Posted September 9, 2011 What about flux use? Could there be a difference factor regarding flux use when comparing soldering to brazing? We see the leaky copper water joints that can happen from too much flux use. Could there be an effort to avoid that issue?
Greg Booth Posted September 9, 2011 Report Posted September 9, 2011 [slight drift. (haha) Greg, are you writing in from a house boat? Sounds pretty bad down your way./quote] ...............we just missed the flooding--the worst is to the east and south. Binghamton got hammered. ...........Greg
Chad Fabry Posted September 10, 2011 Report Posted September 10, 2011 Brass is copper and zinc. Yeah I knew that, but I thought the high zinc content in rod made it something other than "brass". I was wrong. The proportions of zinc and copper in brass can vary widely.
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