Detection of Copper Corrosion ASTM (D130) Detection of Copper Corrosion from Petroleum Products by the Copper Strip Tarnish Test: Some sulfur compounds that remain in the petroleum product after refining are corrosive to various metals. This method is used to determine the corrosivity of petroleum products (including aviation gasoline, aviation turbine fuel, automotive gasoline and natural gasoline) to copper.
from:
See also:
Looks like sulphur is the culprit:
Copper Strip Corrosion ASTM D 130 ? Test Method for Detection of Copper Corrosion from Petroleum Products by the Copper Strip Tarnish Test
D 130 can be used to detect the presence of free sulfur or reactive sulfur compounds. In this test method, a polished copper strip is immersed in 30 mL of gasoline and heated to 50°C (122°F) for 3 hours. The test strip is compared to standard strips and reported on a scale of one to four (one being best).
It is becoming clear that as sulfur levels in gasolines are forced lower, many sulfur species that actually provided protection for copper surfaces are being greatly reduced or eliminated. In extremely low sulfur content reformulated gasolines, levels of free sulfur or reactive sulfur compounds that would not have caused a failed copper strip test in conventional gasolines may now cause a failure. This factor increases the urgency for minimizing contamination with even minor levels of free sulfur or reactive sulfur compounds in processing at the refinery.
Because the reaction that forms copper acetaldehydes is driven by higher pressures.
Jim
I believe copper may work harden if/as it flexes, and can eventually crack, and for this reason is dis-recommeded for gasoline. I'm not aware of any chemical reaction. Both of these ideas are hearsay rather than expertise on my part.
Mickey also >I'm sure I read somewhere that one should not use copper for fuel
copper
copper is used on propane, not natural gas, i believe the reaction has to do with the odorant used in nat gas versus propane.
A similar thing happened on one of the BC Ferries boats a year or two ago. These use big diesel engines for propulsion. There was a copper line leading to a fuel pressure gauge that cracked due to work hardening. It started spraying diesel fuel around, and some of it landed on the exhaust manifold. Instant fire.
The crew managed to put out the fire with the CO2 extinguishing system, and the boat was towed back to port with no loss of life. But it could have been much worse.
Dave
Sorry, but you are wrong. From the Wolverine copper tubing site - re: B149 code. The 2000 edition of the Canadian Standards Association B149 Installation Code, permits only three Types of copper tube for above ground natural gas and propane installations: Type G/GAS, Type L, and Type K. Bare and plastic-jacketed versions of these products are available for this purpose.
For underground applications, Type K copper tube, plastic-covered Type G/GAS or plastic-coated Type L tube are required.
also, from the ccbda site:
The results of a CCBDA survey of gas contractors, have confirmed that copper tube is the most cost-effective material to choose for natural gas distribution in residences.Copper is less than half the material cost of corrugated stainless steel tube (CSST) and is quicker and easier to install than threaded steel pipe. These factors combine to give copper the lowest installed cost when compared to the other materials. For every $100 spent on a copper system, it would cost, on average, $134 for an equivalent system using threaded steel pipe and $144 for the system using CSST.
and:
With soft temper copper tube (Type G/GAS or Type L), a contractor can use a coil of small diameter copper tube, and easily bend it around ducts and other obstructions, connecting it to an existing gas line. This ease of bending and small tube size is especially important in retrofit installations. The time-consuming and messy cutting and threading of steel pipe is eliminated.
Flexible copper gas tube has several advantages over threaded steel pipe and CSST. Copper is easier and faster to install than threaded steel pipe, and unlike CSST, no special fittings or joining techniques are required. Copper tube and flare fittings supplied by different manufacturers are completely interchangeable and readily available?which is not the case with CSST systems.
Operating a natural gas fireplace is easy, and many come with an optional wall thermostat or remote control. The natural, flickering flames have all the look and feel of a wood fireplace, and can help supplement the heating of a home. Natural gas fireplaces are usually very energy efficient, and are generally much less expensive to operate than wood or electric fireplaces. The CCBDA publishes an installer manual, Publication No. 14E, Copper Natural Gas Systems, as well as Publication No. 35, The Real Cost Story?Natural Gas Installed Cost Comparison, and No. 37, Installing a Natural Gas Barbecue. Available free of charge, they are guides for professionals involved in the design and installation of natural gas systems. They are also available on the Association?s website at
and it's not just in Canada. Florida and Alabama too: Copper Delivers Gas Winter 2000
Many builders in Florida are now specifying copper for gas distribution as a result of a concerted program to promote copper tube to deliver natural gas within new homes. To builders and contractors, the main advantage of copper tube over competitive materials is lower cost, plus the fact that the copper is available in long, flexible rolls and is easy to install, which can reduce labor costs tremendously. The program was started in 1995 in Tampa by Peoples Gas, since acquired by Teco Energy, a division of Tampa Electric Company.
When Peoples Gas launched its drive to promote gas usage, builders told the utility's executives that gas installation costs for heating and cooking weren't competitive with electricity. However, Mike Romano, the utility's vice president of marketing, decided to find out what other suppliers of natural gas were doing to stay competitive. At Alagasco, the Alabama gas company, he was attracted to its two-pound-pressure system for distributing gas with copper tube. "With a two-pound system, you can install ½-inch or 3/8-inch copper tube instead of ¾-inch or 1-inch rigid black steel tube," Romano says.
As a result of Romano's investigation, the utility launched its Peoples Gas Advantage Dealer program, which Romano describes as "a partnership with developers and contractor-installers to promote gas service for new homes." The program provides information to builders, training for installers and sales-support materials for homeowners about the benefits of a gas home, plus rebates on gas-appliance installations to defray costs.
I couls add dozens of more citations - but you get my point.
Sure, but that's very low pressure, _and_ low to zero vibration. Not at all like an automotive application.
I would NEVER use copper in an automotive or aircraft application, due to both the work-hardening/fatique issues and the "greenies".My 1928 Chevy had copper lines. So did my 35 Chevy and 37 Terraplane. My old 2 stroke lawnmower built in 1957 HAD copper fuel lines. All of the above had "greenie" problems, and the lawnmower line cracked. (still have the lawnmower).
Aeroplanes use aluminum fuel lines, which also suffer from work hardening and fatigue - but the lines MUST be well supported, and isolated from vibration with rubber flex lines.
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