The most common method for joining copper tubes is?

Soldering is the most common method for joining copper tubes due to its efficiency and effectiveness at lower temperatures compared to other methods. In soldering, a filler metal, often a lead-free solder, is melted and used to join the copper surfaces without causing significant thermal distortion. This is particularly important for copper tubes used in plumbing and HVAC applications, where maintaining the integrity of joints is crucial.

The advantage of soldering lies in its ability to create strong, leak-proof joints that can withstand the pressures and temperatures typical in plumbing systems. Additionally, the soldering process is generally faster and requires less energy than brazing or welding, making it a preferred method for both professional and DIY applications.

Brazing, while also an effective process for joining metals, typically uses higher temperatures and can be more suitable for applications requiring stronger joints or where dissimilar metals are involved. Welding, on the other hand, involves melting the base materials themselves and is less common for small copper tubing as it can lead to warping and requires advanced skills and equipment. Mechanical fastening, while useful in certain contexts, does not provide the same level of sealing and is generally not a common method for permanently joining copper tubes in plumbing.