Measuring, Cutting, Joining Copper Pipes
Some measuring, cutting, reaming, bending, joining, and grooving techniques are related specifically to copper. Different techniques may be used depending on the type and function of the copper pipe you are using.
The next slide presents some commonly used methods to measure copper pipes.
It is extremely important to measure pipes carefully. Click on each of the below given methods of measuring copper pipe to know more:
In the end-to-end method, the full length of the pipe is measured.
Use the end-to-center method for a pipe that has a fitting joined on one end only. Here, the pipe length is equal to the measurement minus the end-to center dimension of the fitting.
Use the center-to-center method with a length of pipe that has fittings joined on both ends. Here, the pipe length is equal to the measurement minus the sum of the end-to-center dimensions of the fittings.
Use the end-to-face method for a pipe that has a fitting joined on one end only. Here, the pipe length is equal to the measurement.
Face-to-face measurement method is used for same situation as the center-to-center measurement. Here, the pipe length is equal to the measurement.
Use the face-to-back method with a length of pipe that has fittings joined on both ends. Here, the pipe length is equal to the measurement plus the distance fitting.
Use the center-to-face method with a length of pipe that has fittings on both ends. Here, the pipe length is equal to the measurement from the center of one of the fittings to the face of the opposite fitting, plus twice the insertion length.
Use the end-to-back method for a pipe that has a fitting joined on one end only. Here, the pipe length is equal to the measurement plus the length of the sweated-on fitting.
Cutting Copper Pipes
Cut copper tubing with a handheld tube cutter, a hacksaw, or a midget cutter.
The handheld tube cutter is preferred because it makes a cleaner joint and leaves no metal particles. Use a tube cutter that is the right size for the copper you are cutting, and make sure that the proper cutting wheel is in place.
After cutting, ream all cut tube ends to the full inside diameter of the tube. Reaming removes the small burr (rough inside edge) created when you cut the pipe.
Bending Copper Pipes
Unlike other types of rigid metal pipe, such as cast iron or steel, copper pipe can be bent. In fact, tests have shown that the bursting strength of bent pipe is greater than that of regular tubing.
Bending reduces the number of joints and fittings in a plumbing system. This can reduce leaks, and ultimately save on the installation time and costs as well.
Place tube-bending springs on the outside of the tube to prevent it from collapsing while bending it by hand.
Joining Copper Pipes
Copper can be joined in many ways, including by a sweat joint, a compression joint, or a flare joint.
The method used for joining depends on the plumbing application and environmental factors. Sweat joints, for example, require a heating process. This method should not be used when a fire hazard exists at the job site.
Joining Copper Pipes
Soldering is a type of heat bonding in which a copper pipe is joined when a soft filler metal is melted in the joint between the two pipes.
Solder fittings are made slightly larger than the pipes to be joined, leaving only enough space for solder to flow into the joint.
Tools used to solder copper tubing to fittings include a tube cutter, fitting brush, solder, flux brush, and soldering torch.
Creating Compression Joints:
A compression joint is a mechanical joint that is made by measuring, cutting, and reaming the pipes and using compression fittings.
In this method, a threaded nut is tightened to squeeze a compression ring to seal the joint. This kind of joint is often used for joining refrigerant tubing.
Creating Flare Joints:
Flare joints may be required in an installation where a fire hazard exists and a torch for soldering or brazing is not permitted.
A flare joint is made by measuring, cutting, and reaming the pipes and using flare fittings. This kind of joint is commonly used to join soft copper tubing.
Kinds of Flare Fittings
Two kinds of flare fittings are popular: the single-thickness flare and the double-thickness flare. For both types, you use a special flaring tool to expand the end of the tube outward into the shape of a cone, or flare.