Characteristics of Flat-Seated Valves with Broader Seat-Face : 8 th Report, Experimental Research on Disc Valve

抄録

This paper presents the results of experiments on flat-seated valves with broader seat-face, discharging water into the air under a constant head of about 194 cm. Five valves were used in all, of which the first four had diameter d smaller than seat-face diameter d₁ and the last one had d equal to d₁. When the lift of the vales with d<d₁ is gradually increased, the steam flowing out separates partially from the seat-face at a certain valve-lift, and then separates completely from the seat-face at a higher lift and becomes free jet. When the valve is closing the free jet finally clings to the seat-face at a very small valve-lift. These are represented by three special points on the characteristic curve of each valve. In case of the valve with d=d₁, there are one separating and one clinging point on the curve, just as the valves with d>d₁ on which the authors have already reported. They try to give some explanations for these phenomena hereunder.