Boilermakers make and install boilers and other large containers that house gases or liquids such as oil. Job duties include reading blueprints, casting pieces and bending them into shape, and welding or bolting pieces together. Boilermakers also test completed boilers and perform routine maintenance. They often upgrade boilers to meet environmental standards and increase their efficiency. Boilermakers can work for refineries or construction or natural resource companies, or they can find careers as metal fabricators or power or water plant operators.