Abstract: The invention relates to the method for the manufacture of a ball valve (1) between two tubes (3, 4). In the valve, the valve ball (2) and the ends (7, 8) of the tubes sealed against it are surrounded by the sleeve-like cover (10), which is penetrated by the spindle (13) provided with a handle, the spindle rotating the valve ball for opening and closing the valve. According to the invention, the cover (10) is connected to the mantle surfaces of the tubes (3, 4) by beam welding, such as laser or electron beam welding. For this purpose, the flank of the tube (3, 4) is provided with a front face achieved by a narrowing beveling, and the cover (10) contains a parallel end face brought against it so that the fastening can be performed by directing the welding beam (31) between the faces in their direction. The spindle (13) operating the valve ball (2) is surrounded by the support sleeve (14), which can be attached to the aperture formed to the cover (10) in a similar way using the beam welding technique.

Abstract: The invention relates to a ball valve (3) with full opening between two tubes (1, 2) and the manufacturing method thereof. The ends (6, 7) of the tubes are sealed in the valve against the valve ball (5) opening and closing the valve and rotating about its axle (17), the diameters of the flow openings (9, 10) of the valve ball being substantially the same as the diameters of the flow cross sections of the tubes. Around the valve ball and the ends of the tubes there is a sleeve-like casing (8) secured by its ends (15) to the sides of the tubes (1, 2). According to the invention, a protrusion is formed in the ends of both tubes (1, 2), comprising an annular sealing (11), and the casing (8) is formed with a tapered reduction towards its ends so that the valve ball (5) and the ends of the tubes are located in the space (16) defined by the casing (8) of the valve.