| 摘要 |
<p>934,502. Automatic pressure control systems. INSTITUT DE RECHERCHE DE LA SIDERURGIE FRANCAISE. Jan. 27, 1960 [Jan. 28, 1959; May 5, 1959; Dec. 22, 1959], No. 2949/60. Class 38 (4). [Also in Groups XIII and XXVIII] Oxygen from a tube 2 is passed into molten pig iron in a steel converter 1 and the gases from the vessel are collected in a hood 3 (see Group XXVIII) and pass to a conduit 7 in which they are cooled (see Group XIII) by gas or steam, the injection of which is controlled according to the pressure in the hood 3, detected by tubes 11, so that the pressure at the bottom of the hood is maintained equal to that of the surrounding atmosphere and contact of the gases with the air is kept at a minimum. The three pressure tubes 11 at one level in the hood 3 and a reference tube 12 outside the hood communicate with an electric switching device 13 coupled to a pressure-measuring device 14. Cams in the device 13 cause consecutive communication of the tubes 11 with a chamber of the device 14, another chamber being permanently connected to the tube 12 to detect pressure differences. The device 14 passes a signal to a potentiometer 15 which adds integral and differential components and acts on pneumatic relays 17 and 18 to regulate a valve 19 controlling the flow of cooling gas or steam and to move a pneumatic slide 10 and an injector 9 for the cooling fluid, with respect to a Venturi tube 8, to determine the flow and entraining of the gases. In Fig. 4 (not shown), there is no Venturi and the entraining of the gases to be cooled is controlled by regulation of two opposed injectors for the cooling gas or steam, along the axis of the conduit 7 as in the ease of the injector 9. There may be an auxiliary fan.</p> |
