Abstract: A primary object of the present invention is to provide a static-type mixing and stirring device which allows for reduction in size of the device and for substantial reduction in the costs of manufacturing the device, while at the same time lowering pressure loss and enhancing the mixing and stirring performance of the device. To achieve the object of the present invention, the static-type mixing and stirring device comprises a cylindrical case body, a plural number of disk-shaped elements—equipped with plural kinds of holes at prescribed intervals—combined and fitted in sequence into the case body, and joint metals removably fitted to the ends of the inlet and outlet of the body case.

Abstract: A ball valve includes a valve seat assembly having a lower valve seat, an upper valve seat, packings located in openings formed by apertures in abutting sides of the valve seats, and annular retainers located in central holes through the packings. Each of the components has a profiled inner surface for slidable contact with the ball controlling communication between the fluid passages in the valve box. The use of such components for the valve seat simplifies manufacture, gives a wider choice of materials to be used and reduces costs of repairs.

Abstract: A ball valve is provided with a valve case forming an internal space that is centrally extending to opposite inlet and outlet sides. A ball valve element is disposed within the interior space and has a bore extending therethrough, a valve seat rotatably supports the ball valve element and a valve stem is fixed to one side of the ball valve element and has an operating lever at one end of the valve stem projecting therefrom outside the valve case. A flow adjusting internal valve assembly means is provided in the bore which comprises an internal cylindrical valve casing in the bore with an internal valve seat portion, and an axially movable internal valve element disposed within the internal cylindrical valve casing. The internal cylindrical valve casing comprises an internally threaded large-diameter portion at its inlet side, a small-diameter guide bore portion at its outlet side and an intermediate portion positioned therebetween, having a tapered inner surface providing the internal valve seat portion.