A large manually operated leak-proof corrosion-proof low-cost shut-off or stop valve for handling high pressure refrigerant liquid and/or gases is disclosed. The valve comprises a valve body formed of two sheet metal hemispheres electron-welded to the periphery of a circular metal valve plate which has an aperture therethrough. Hollow cylindrical metal tubes entend into circular holes formed in the hemispheres and are electron-welded to the hemispheres along the edge of the circular holes. One tube on each hemisphere serves for fluid flow. Another internally and externally threaded tube on one hemisphere serves as valve sleeve through which a manually rotatable and axially shiftable externally threaded valve spindle extends. The inner end of the valve spindle is secured to a valve disc which cooperates with the aperture in the valve plate. In the method, components to be welded together are assembled and rotated with respect to a stationary electron welding beam. The weld is formed solely of melted and resolidified materials from the components being joined. The electron welding beam is applied to the interior of each hemisphere to attach the metal tubes thereto. The electron welding beam is applied to the exterior of each hemisphere to secure it to the metal valve plate. This ensures that a weld extends entirely through the mating surfaces being joined.