Abstract: A firefighting nozzle for discharging a foam and water mixture. The firefighting nozzle has an inner nozzle concentrically positioned within an outer barrel. A baffle in the shape of an inverted cone is position at the outlet of the inner nozzle. The axial position of the baffle determines the flow rate of the foaming agent. The inner nozzle itself is also axially movable within the bore of the outer barrel, the axial position of the inner nozzle determining the flow rate of water between the outer barrel and the inner nozzle.

Abstract: A fluid driven pump uses a working fluid under pressure to run a pump for pumping a product fluid. The pump includes first and second cylinders positioned end-to-end. Each cylinder houses a piston, the pistons being linked so as to move together. A piston rod projects from an end of one of the cylinders and operates valve gear which alternatingly direct working fluid to opposite sides of one of the pistons, or to opposite sides of the assembly formed by the two linked pistons. This arrangement results in the reciprocating movement of the pistons which can then be used to pump the product fluid. In another embodiment, two pumps of the type described above are used with the piston rod of each being used to operate the valve gear controlling the other. In yet another embodiment, a rotary turbine, driven by working fluid under pressure and having a common shaft with the impeller of a centrifugal pump, is used to pump the product fluid.