Читать книгу Mechanics of the Household - E. S. Keene - Страница 46

—The damper regulator used on a steam boiler is a simple device that automatically controls the draft dampers by reason of the changing pressures of the steam. The object of the damper regulator is to prevent the generation of steam in the boiler beyond a certain pressure at which the valve is set. This point is usually 3 or 4 pounds below the pressure at which the safety valve would act. If in proper working order the damper regulator will so control the dampers that the boiler will always contain a supply of steam, but the pressure will not reach a point requiring the action of the safety valve. Fig. 51 illustrates its connections with the furnace dampers. In Fig. 18 the regulator appears at D. In external appearance and in operation of the dampers, it is the same as the regulator for a hot-water boiler but its internal construction is simpler. Fig. 50 shows its construction. It is attached to the steam space of the boiler at E. The steam pressure acts directly on the flexible metallic diaphragm B. As the pressure of the steam approaches the desired amount the diaphragm is raised and with it the lever V. A chain D, attached to the end of the lever, opens the check draft, and another at C closes the draft damper. When the steam pressure falls, the diaphragm lowers the lever and the dampers are restored to their original position. The same movements are repeated with each rise and fall of the steam pressure.

Fig. 52.—Damper regulator for hot-water boiler.