A pipe fitter installs, maintains, and repairs piping systems for steam, water, oil, gas, and other fluids in industrial, commercial, and residential settings. Key responsibilities include reading blueprints to lay out and measure pipes, welding, threading, and assembling pipe sections, and performing leak tests to ensure system integrity. Pipe fitters work with various materials, adhere to strict safety regulations, and collaborate with other trades in diverse environments, from factories to construction sites.