Metal Associates – Copper Sizing

Copper tubes and pipes are frequently used in the plumbing industry because they can be shaped into 90 degree angles and easily soldered or compressed together to form a connection. While copper is becoming more costly, it is still a good choice because of its high resistance to corrosion which makes it well suited to long term uses.

Copper tubing comes in several common size types: Type “K”, type “L”, type “M” and type “DWV”. These sizes are all based on the size of the inside and outside diameter in relation to the tube’s overall thickness. Type K has the thickest walls among these four pressure ratings and it is usually used in deep underground installations for water flow. Most construction standards require an underground type K tube to be covered with a polyethylene sleeve for enhanced anti-corrosion protection. Type L pipes have a thinner wall and can usually be found in residential and commercial plumbing with low pressure water supply. Type M has an even thinner wall, and it is also used in residential and commercial water flow applications. This type is usually has red print on it to distinguish it from the other types. Finally, type “DWV” copper tubing is the thinnest, and can usually only be used for applications where no extra pressure is forced through the tube. Examples of this would be drains, waste and vent lines. DMV copper piping can range from 1.25’’ to 2” in diameter.

The four copper sizing types mentioned above are commonly known by experts in the plumbing industry in the United States. Knowing the difference between them is important when installing new pipes for a specific building or construction application. In the refrigeration industry, a different kind of copper piping called ACR is used. ACR stands for Air Conditioning and Refrigeration field services. These pipes are the same size, but different varieties of ACR pipe are manufactured with different specifications. Most types of ACR pipe are processed without using oils that would interfere with the products used to lubricate a refrigerator’s AC system.

Copper sizing varies from on industry to another as size is usually determined by a particular application. At metal associates, we try to distribute copper sizes that work for whatever industry you may operate your business in so that your application is fitted with the perfect materials.