Patent GB-358659-A (GB)
Title: Improvements in and relating to the feeding of vapour turbines
IPC: F01K9/02
Filed: 1930-08-25
Abstract: 358,659. Feedwater supply apparatus. BR€UER, E., 4, Kunz-Buntschuh Strasse, Grunewald, Berlin. Aug. 25, 1930, No. 25318. [Class 123 (ii).] The feed device for the liquid heater supplying a vapour turbine is operated by steam or liquid of different boiling point than water such as ammonia or diphenyl, intermittently admitted and comprises a chamber shut off from the atmosphere and completely enclosing the moving parts, exhaust from the chamber being condensed in a heat exchanger after giving up its heat to the feed. The heater for the working fluid of a vapour turbine 1 comprising a mixture of steam and water globules produced by nozzles 2 consists of a coil 4 heated by a burner 6 the supply of fuel to which is controlled by a valve 30 subjected to the pressure in the main pipe 3. In the form shown a steam generator comprising water tubes 7 and annular headers 8, 9, is also heated by the burner and supplies steam for the feed apparatus which is otherwise obtained by expanding the pressure water from the heater. The pressures in the heater and steam generator are 150, 155 atmospheres respectively. Feed passes from a condenser 14 to a feed cylinder 11 and thence to the inner coil 18 of a heat-exchanger surrounding the heater jacket and to the heater. Exhaust steam from the feed cylinder is condensed in an outer coil 19 of the heat-exchanger, condensate being returned through valves in an upper extension 12 of the feed cylinder and a container 22 to the steam generator. A pipe 25 connects a lower extension 13 to the coil 18. The feed cylinder accommodates a piston 33 having a piston rod formed at its lower end as a piston 34 and provided at its upper end with a feather 42 disposed in a groove 43 in a drag valve 40 sliding in the extension 12, this valve being held in its end positions by means of a spring 38 and lever 36. When the piston 33 moves upward due to pressure water from the heater acting on the piston 34, the space above it is connected with the steam generator by a pipe 10 and the contents of container 22 are discharged into the generator. As the piston descends and forces the water into coil 18 the valve 40 is actuated near the lowest position of the piston and the passage from the steam generator is closed while a connection 21 between coil 19 and container 22 is opened. The piston 34 may be omitted and a spring provided to effect the upward movement of the valve 40; or the feed cylinder may be so placed that the water from the condenser 14 forces up the piston 33 as soon as the steam pressure above it has been sufficiently lowered by condensation in coil 19. Adjustment of a valve 26 in pipe 10 varies the periodicity of the pump. Or the valve 40 may be connected to an iron core moving within a coil intermittently excited by means of a clockwork-driven contact maker having adjustable speeds. In a modification pressure water from the heater is expanded to provide steam for operating the feed device which comprises two connected pistons of different areas working in superposed cylinders and a drag valve located on a lower extension of the piston rod. In this form steam generated from the pressure water acts under the larger piston against spring pressure, water sucked from the condenser 14 being expelled from the smaller cylinder to the coil 18. In the downstroke of the pistons the drag valve is changed over and a passage opened for evacuation of condensing steam to the coil 19. A non-return valve is provided in the larger piston to prevent excessive pressure arising from leakage past the smaller piston. The lower end of coil 19 leads to the container 22 which in this embodiment is preferably connected by way of a float valve to the pipe coming from the condenser 14. A balancing storage vessel 60 protects the turbine from the effects of temperature and pressure variations due to an intermittent feed.