Water cooled friction stir welding tool

Abstract

The friction stir welding tool is fixed in the chuck of a specialized machine. After the tool rotation is switched on and the welding process begins, cooling water is supplied to the tool working blades through the inlet pipe, which, when the tool rotates, similarly to the action of a centrifugal pump, under the action of centrifugal forces, pump water into the spiral channel and then into the outlet pipe. In this case, the water cools the blades and the inner part of the shoulder. Calculation studies show that with an increase in the required decrease in the temperature of the shoulder working surface, the thermal power transferred to the cooling water increases, with a decrease in the shoulder thickness this increase is more significant. With the required temperature decrease by 200°C with a shoulder thickness of δ = 20 mm, the water consumption should be 0,25 g/s, with a thickness of δ = 5 mm this consumption increases to 0,6 g/s. With the required temperature reduction by 400°С at a shoulder thickness of δ = 20 mm, the water consumption increases proportionally to 0,75 g/s, at a thickness of δ = 5 mm, this consumption increases to 1,7 g/s.