A Welder is a person who has training in and is capable of welding ferrous and non-ferrous metals in all positions, on both plate and/or pipe, using SMAW, GTAW, and FCAW processes. Welders use manual or semi-automatic welding equipment. They use flame-cutting, brazing and air-arcing equipment. Additionally, they use machines such as brakes, shears and other metal straightening and bending machines. Welders generally plan work from drawings or by analyzing the job tasks, determine the materials required and welding processes, then use their knowledge of welding to complete the job. They may specialize in certain types of welding such as custom fabrication, ship building and repair, pressure vessel welding, pipeline construction welding, structural construction welding or machinery and equipment repair welding. Workers use blueprint symbols to determine machining operations. They check product specifications using precision measuring instruments, and maintain equipment and replace parts when required.