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Soldering and Brazing Copper Pipes and Joints

Last Updated on Thursday, 13 May 2010 21:42 Tuesday, 04 May 2010 17:00

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Articles - Soldering

SolderCoilWhen we talk about soldering and brazing, we are essentially speaking of the same thing. In both cases we are talking about applying a flame to a piece of pipe for the purpose of joining it with a fitting. The simple difference between soldering and brazing is the temperature at which they are achieved. Soldering requires lower temperatures, usually somewhere between 350 and 600 degrees Fahrenheit, where as brazing requires higher temperatures between 1100 and 1500 degrees. According to the American Welding Society the magic number is 840 degrees Fahrenheit. Below this temperature any joining process is called soldering, and any joining process above it is brazing.

Active construction codes and the circumstances of the welding situation largely determine whether the situation should be subject to soldering or brazing. Where greater joint strength is necessary, brazing is a good bet. Other than this factor, soldering is generally used for systems that are as hot as 250 degrees Fahrenheit. Brazing is more often used for pipe systems in the area of 350 degrees.

Brazed systems often hold less rated pressure than soldered systems on account of the higher temperatures utilized in the brazing process. Although brazed joints are more supportive of joint strength, this pressure issue should be considered.

A lot of people use irresponsible, ineffective, and unsafe tactics when soldering their own copper pipes and fittings. Soldering and Brazing are the least understood methods for joints and fittings, and the irony lies in the fact that they are the most often used methods as well. A simple mistake can lead to leaking lines and faulty joints. Errors that lead to improper installation include:

  • Poor preparation of joints prior to soldering
  • Lack of support and hanging during the welding process
  • Incorrect control and distribution of heat throughout the welding process
  • Incorrect application of metal filler
  • Incorrect amount of metal filler
  • Pre-tinning of joints prior to assembly
  • Shock from cooling or wiping hot filler metal following welding

The welding process, whether it is soldering or brazing, is a relatively easy endeavor for the homeowner. However, it is very easy to be unsafe and inefficient when soldering copper on your own. Pay attention to these tips, and research further into soldering and brazing copper pipes. Educate yourself before taking a torch to your pipes; it could make the difference between a strong and a faulty joint.

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