| 摘要 |
<p>994,694. Valves. CHEMETRON CORPORATION. Aug. 11, 1961 [Aug. 25, 1960], No. 29119/61. Heading F2V. A spherical ball valve is provided with seating rings, slidable in a tapered housing and adjustable from outside the valve. As shown in Fig. 1, the ball 14 is rotatable in a housing having tapered sides which receive seating rings. Each ring comprises a retaining element 51 for receiving a suitable resilient seal 50, whose width at any point is greater than the corresponding width of the element 51. The rings are carried by projections 60 of an element 61 which is screwed on to a nut 23 surrounding the valve spindle 31. The nut can be rotated from the outside through an hexagonal part 24 to move the rings axially, and hence the plug, to adjust the sealing. In a modification, Fig. 3, a resilient 0-ring seal 90 is provided, carried by a retainer 91 which is adjustable by rotation of a bonnet 70. In this case, the faces of the plug from which the through bore extends are also tapered. The plug and rings may be moved through the top of the body. A drain plug 15 may be provided. The form of valve shown in Fig. 3 is suitable to be made from rigid plastic material.</p> |
