Copper Tube


Soft copper

Soft (or ductile) copper tubing can be bent easily to travel around obstacles in the path of the tubing. While the work hardening of the drawing process used to size the tubing makes the copper hard/rigid, it is carefully annealed to make it soft again; it is therefore more expensive to produce than non-annealed, rigid copper tubing. It can be joined by any of the three methods used for rigid copper, and it is the only type of copper tubing suitable for flare connections. Soft copper is the most popular choice for refrigerant lines in split-system air conditioners and heat pumps.

Flare connections

Flare connections require that the end of a tubing section be spread outward in a bell shape using a flare tool. A flare nut then compresses this bell-shaped end onto a male fitting. Flare connections are a labor intensive method of making connections, but are quite reliable over the course of many years.

Rigid copper

Rigid copper is a popular choice for water lines. It is joined using a sweat, compression or crimped/pressed connection. Rigid copper, rigid due to the work hardening of the drawing process, cannot be bent and must use elbow fittings to go around corners or around obstacles. If heated and allowed to slowly cool, called annealing, then rigid copper will become soft and can be bent/formed without cracking.

KSD – Product Availability & Highlights

  • Nitrogenized ACR Diameters from 3/8″ O.D – 3 1/8″ O.D.
  • Nitrogenized types K & L
  • Dehydrated Refrigeration Coils diameters 1/8″ O.D – 1 5/8″ O.D.
  • Plastic-Coated ACR Copper Tube & Plastic-Coated Dehydrated Refrigeration coils also available
  • Each ACR Copper Tube is charged under pressure with 99.9% pure nitrogen


    • Meets applicable ASTM standards: B-88, B-306 & B-280
    • NSF approved
    • Made in the USA