LIQUID FLOW METERING

摘要

1,262,388. Valves. REPUBLIC STEEL CORP. 11 Nov., 1969 [25 Nov., 1968], No. 55181/69. Heading F2V. [Also-in Division C7] A valve, which is suitable for controlling the flow of hot and corrosive liquid metals, comprises a U-shaped frame 8, a body member 7 which is secured to the frame as by bolts 19 and which has extending therethrough a passage 14, and a valve member 9 which is retained between members 8 and 9 by means of a flange 17, is manually rotatable as by a handle 11, and has extending diametrically thereacross a slot 18, the degree of relative registration between slot 18 and passage 14 determining the amount of liquid metal which can pass through passage 14. The frame, body member and valve member are all made from refractory material such as graphite. The valve may be used in an apparatus (Fig. 1, not shown), for vapour depositing of a layer of zinc on a steel substrate. When so used, the valve is immersed in a heated reservoir of zinc and has connected to one end of passage 14 a pipe (4) which leads to a heated vacuum chamber (5), the amount of zinc entering the other end of passage 14 and subsequently passing to the vacuum chamber being dependent upon the setting of the valve. Ingress of air into the vacuum chamber is prevented by locating the valve below the level of liquid zinc, and wetting of the valve component parts is obviated if the zinc is maintained at a temperature of between 788‹ and 1200‹ F. The vacuum chamber is maintained at a pressure of 10-3 and 10-4 millimeters of mercury.