As a vessel welder, your responsibilities include fitting and welding metal pressure vessels based on drawings provided by clients, using techniques that adhere to all specifications for vessels, piping, and welding assembly based on American Society of Mechanical Engineers (ASME) criteria. You also work on the layout and fabrication of vessels and their components and calculate the take offs, layout and fit shells, and fit nozzles. Some jobs require the use of specific machinery. Other duties include inspecting and documenting each product that is produced, ensuring that products are compliant with all laws and regulations, and working closely with other fabricators to improve your skills.