Abstract: A method of mounting valve seats in a butterfly valve comprising a valve body mounted in a valve stem in a valve housing. The valve seats are attached to the valve housing so as to contact the periphery of the valve body when the valve is closed. End surfaces of the valve seats are adjusted relative to the valve stem and seal members by means of first bolts. Then, the first bolts are replaced with third bolts for pressing the valve seats against the periphery of the valve body.

Abstract: A cylindrical valve body for a sleeve valve including the valve body to be secured to the upper wall of a reducing chamber and a valve cylinder gate having open upper and lower ends and slidably fitted in the valve body, the gate communicating at its upper end with an inlet elbow for pressurized water. The valve body is formed in its peripheral wall with a multiplicity of straight bores each having a cylindrical nozzle member fixedly fitted therein and provided with an outwardly tapered port. This construction renders the tapered ports easy to form in the wall of the valve body. The tapered port is closable with a plug including a conical head in conformity with the tapered port and a threaded pin projecting from the top end of the head by inserting the plug into the port and screwing a nut on the threaded pin. By altering the number of the tapered ports so closed, the distribution of open ports is variable to improve the flow ratio characteristics of the valve body.