Friction Stir Welders Explore MTI’s most popular Friction Stir Welding machines for industry. Select a welder below for detailed information and specifications. GG Series Friction Stir Welder View Machine RM Series Friction Stir Welder View Machine PM Series Friction Stir Welder View Machine LS Series Friction Stir Welder View Machine Our Commitment Quality is at the core of our ingenuity MTI brings the highest possible degree of safety and quality, whether it’s a part we’re welding or a machine we’re building. We are equipped to produce parts for the most sensitive environments and exacting standards.