The purpose of this part of ISO/TR 10809 is to assist the design engineer to understand and to acquire knowledge of how the family of cast iron materials can be welded and to utilize this technology to its full advantage in selecting the most appropriate technique for a particular cast iron. Because the application of welding technology and the metallurgical implications of welding are not scientific disciplines normally taught to engineering students, such users often have limited knowledge of the fundamentals underpinning welding technology for cast irons. This part of ISO/TR 10809 explains what can be achieved, what cannot be achieved and why. It is not designed to be a textbook of welding technology. It helps users to select the most appropriate welding process and conditions for a specific application. This part of ISO/TR 10809 covers production (including finishing and joint welding) and repair welding.