GB497452A - Apparatus for use in measuring the dryness fraction of steam - Google Patents

Abstract

497,452. Determining the moisture content of steam. BEALE, E. S. L., and DOBBIE, McINNES, Ltd. Aug. 28, 1937, No. 23598. [Class 97 (iii)] The rate of flow of the steam under test through a conduit is adjusted so that for any pressure the product W x L has a con. stant predetermined value (W being the flow in 1b. per min. and L the latent heat of the steam) and the moisture content of the steam is then determined directly from the heat input necessary to render it just dry, heat losses being approximately compensated for. As shown, a test flow of steam passes from the main pipe 2 over the electric heater 5, which is connected through a wattmeter 13 and then passes through the valve 7 and orifice 16 to a condenser 21 at atmospheric pressure. In use, the valve 7 is adjusted until a pressure gauge 20, connected to the space above the orifice 16, gives an indication corresponding to the pressure in the main pipe 2 on a modified scale. A scale 20a is provided to enable zero adjustment of the gauge 20 in accordance with the barometric pressure. Thermocouples 8, 9, and a millivoltmeter 10 enable the point at which the steam first becomes dry to be determined. The wattmeter 13 is provided with a scale 136 for zero adjustments in accordance with the pressure in the main 2. Specification 444,807 is referred to.