In order to meet this standard the propane torch manufacturers then began producing dual fuel torches that could use "Propane" as the primary fuel for soldering and "Mapp" for brazing. Per the American Welding Society "Brazing" is the act of joining two metals with a liquid fill metal with a melting range between 12degF. When running copper under a slab we are required to use wrought copper fittings and all joints must be brazed. The plumbing codes were again amended to prohibit the use of soldered joints on copper lines run under a slab. This pre-combustion swirling action effectively increased the output temperature of the flame well within the requirements for the new alloys. To compensate the propane torch manufacturers developed torches that have the combustion air intake directly on top of the regulator and there is a spiral wire inside the tube from the air intake to the torch tip, which causes the fuel/air mixture to swirl as it travels up to the tip.
In commercial plumbing there are conditions which require a solder with a higher tensile than what is provided by Alloy SB-5(95-5 Tin-Antimony) solder so they have now developed ASTM Alloy E (95/5 Tin/copper) with a melting temperature of 440-500degF and ASTM Alloy HB (Tin/Antimony/Silver/Copper & Nickel) with a melting temperature of 460-630degF. It is true that with a melting temperature range of 452-464degF the new Alloy SB-5 (95/5 tin/antimony) solder proved to be a bit more difficult to handle than its predecessor, Alloy SN-50 (50/50 tin/lead) solder with a temperature range of 361 to 421, especially when working with the older style pencil flame propane torches This is the alloy, which is still most commonly in use. We then adopted the use of ASTM alloy SB-5, which is a 95/5 mix of Tin and Antimony.
Antimony vs nodebox free#
In the early 1980Âs the American Society of Testing and Materials amended ASTM standard B-61-"Standards for Safe Potable Water" to require that we use lead free solder or solder which contains not more than 0.20% lead. Ordinary 50/50 tin/lead solder (ASTM alloy SN50) has a melting temperature of 361 to 421degF, which can easily be applied with a common pencil flame type propane torch. In fact the alloys used for plumbing purposes rarely exceed 600degF. The American Society of Welding defines "Soldering as the act of joining two metals by means of a filler metal with a melting temperature under 840degF. While that may be your understanding, I hate to be the one to inform you but it is totally wrong, but then, dont be disheartened because most homeowners and neophyte handyman plumbers share it. Antimony has been worth more than $4 a pound for the last 4 years.Quote: "but as I understand the silver stuff is better for lower temp torches but since i went with mapp I guess it's not an issue?" Some scrappers are ahead of the game and are already scrapping computer, phone and television parts that contain high amounts of antimony. Scrap yards may start requesting antimony scrap specifically or items containing antimony. Today antimony is produced in a handful of countries, including China, which holds 75 percent of the world’s reserves, and accounts for almost 90 percent of world production, which totaled 135,000 metric tonnes in 2010.Īlthough current known global reserves are expected to be depleted in approximately 13 years, and a shortage would dramatically affect the Western economy and lifestyle (according to a UK government report), scientists expect that more deposits will be discovered.Īs you have read, scrap in the future will be much more than metal goods. More recently the semiconductor and microelectronics industry has begun using its compounds in the manufacture of silicon wafers, diodes and other components. This same property makes it a key part of computer and television screen manufacture, in which it is used to ensure that no microscopic bubbles remain in the glass when it cools. Some 60 percent of all antimony produced today is used in the clothing and fabric industries in flame retardants, most often in its trioxide form, since the material inhibits combustion by reacting with oxygen and hydrogen atoms. It is often alloyed with lead and with tin, and is widely employed for lead-acid battery plates, bullets and cable sheathing. Modern uses of Antimony also take advantage of its hardening effect in alloys.
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