Brazing is a process than involves bonding two metal objects by creating a tight and secure seam. Very similar to welding, brazing is often accomplished with the use of an acetylene torch and is particularly effective when used on sections of metal pipe. Here are some general tips on how to braze steel, copper or other common metals used to manufacture pipes.
One of the first steps in brazing steel or other metals is to gather your safety supplies. Just as with welding, you should wear safety goggles equipped with dark lenses. Heat resistant gloves to protect your hands are also necessary. Make sure the goggles are dark enough to provide the protection you need, but no so dark that you can’t see what you are doing with the torch. If you don’t have safety goggles of this type, a lighter tinted welder’s mask will also work.
You will also need clamps or weights that will hold the two sections of pipe together while you braze. If possible, position the sections so you can easily see all the way around the area where the seam is to be placed. This will save time, as it will not be necessary to begin the seam, then reposition the piping in order to complete the task.
When beginning the process of brazing, make sure to turn on only a small amount of the acetylene fuel. At first, you want just enough to light the flame. Once the torch is lit, you can adjust the flame to whatever intensity you will need for the job. Keep in mind that the flame will smoke a bit at first, but as you increase the flow of oxygen, the smoking will subside. At this point you are ready to begin the actual brazing.
To begin to braze, use the flame to heat the area where the seam will be made. Once the area is sufficiently heated, touch the brazing rod to the area. Make sure the rod is not in the direct line of the flames. As the rod begins to flow and create the bond, move the rod along the joined area but in the direction opposite of the flame. This will make it possible to apply the bead and then drag the flame over the bead to help create the seal.
Once the braze is complete, turn the torch off and set it to one side. Allow the joint to cool, then inspect the work. Ideally, the brazing will be neat and uniform while creating a tight seal. Should the seal of the braze not be as sturdy as you would like, light the torch and make a second round. In most cases, no more than two rounds will complete the project.
People who are not used to working with an acetylene torch would do well to not attempt to braze any type of metal objects. Instead, pay to have the work done by a professional. Many machine shops can handle the task for you at a reasonable cost. Plumbers are also often proficient with brazing and can take care of the task as well.