Abstract: A positively controlled ball valve for flowing fluids, in particular water, for instance for use in snow making machines. The valve includes a valve housing (1) having a flow passageway (3) for the water (7), a valve seat (9) arranged in the flow passageway (3), and a valve ball (10) which is movable towards and from the valve seat (9). A force actuation device (4) having a piston rod (20) positively acts on the valve ball (10), which is movable in a race (11) in the valve housing (1). The race extends from the valve seat (9) obliquely outwards-rearwards, upstream of the flow of water (7). The force actuation device (4) is formed with a piston rod (20) arranged for being able to force the valve ball (10) in the direction away from the valve seat (4) and into the race (11) for the ball. The piston rod (20) is arranged to act on the valve ball (10), in the first stage of the opening of the valve, so that the ball at least partly rolls out of the valve seat (9).

Abstract: A method for artificial making of snow by a snow making machine (1) comprising a series of nozzles (8) arranged to provide a tubular flow (2) of bulk water drops which are moved along by an inner flow (3) of feeder air, and a series of atomizing nozzles (10) arranged to provide a flow of super cooled nuclei which are created at or adjacent the outer periphery (9) of the snow making machine (1) by a series of atomizing nozzles (1) which are distributed round the snow making machine and radially outside and preferably downstream the bulk water jet nozzles (8) as seen in the flow direction, whereby there is formed a shell (5) of super cooled nuclei extending circumferentially round the flow (2) of bulk water drops, which successively, and over a relatively long way of movement provides a freezing of the drops of water in the flow (2) of bulk water drops.