ASVAB (Armed Services Vocational Aptitude Battery)Auto and Shop Information (AS)Medium
A plumber is attempting to join two pieces of copper pipe using a soldering torch. Before applying the solder, what is the crucial step that must be performed to ensure a strong, leak-proof joint?
- AWrap the joint with Teflon tape.
- BApply flux to the heated pipe joint.
- CHeat the solder until it melts.
- DClean and deburr the pipe ends thoroughly.
Show answer & explanationAnswer & explanation
Correct answer: D. Clean and deburr the pipe ends thoroughly.
For a strong solder joint, the copper surfaces must be absolutely clean and free of oxidation or burrs. Cleaning and deburring allows the solder to flow properly and create a molecular bond with the copper.
Why the other options are wrong
- A. Teflon tape is for threaded pipe joints and is not used in soldering applications.
- B. Flux is applied *after* cleaning and *before* heating the pipe, as it helps clean further and allows solder to flow, but cleaning is the initial crucial step.
- C. Heating the solder is part of the process, but without proper joint preparation, it won't adhere correctly.
Soldering Preparation
The critical steps taken before applying heat and solder to ensure a clean, strong, and leak-free joint.
- Cleanliness is paramount for solder adhesion.
- Oxidation prevents proper bonding.
- Deburring removes sharp edges that impede flow.
Memory trick: Clean copper craves contact.