US2568567A - Attemperator regulating the tem - Google Patents

Description

Sept. 18, 1951 c, SPARKS 2,568,567

ATTEMPERATOR REGULATING THE TEMPERATURE OF SUPERHEATED VAPOR Filed Sept. 25, 1947 INVENTOR Cedric Harold Sparks ATTORNEY Patented Sept. 18, 1951 UNITED STATES PATENT OFFICE ATTEMPERATOR REGULATIN G THE TEM- PERATUBE OF SUPERHEATED VAPOR Cedric Harold Sparks, London,

England, assignor to The Babcock & Wilcox Company, Rockleigh,

N. J., a corporation of New Jersey Application September 25, 1947, Serial No. 776,076 In Great Britain October 2, 1946 3 Claims.

' drum and the bottom of the steam collector being connected with the drum by a number of nipples and being provided in the top thereof with outlets for the wet steam. With such an arrangement the possibility of water hammer is avoided since no Slugs of water can pass to the superheater, but part of the condensate is liable to drain back into the steam and water drum. An object of this invention is the provision of condensing means for controlling the temperature of superheat which renders possible the utilization of all the condensate, while avoiding the danger of Water hammer. Another object is the provision of an improved method of regulating the temperature of superheated vapor.

The present invention includes a superheat regulator comprising a condenser disposed in the vapor flow path between a source of vapor and a superheater, together with means for withdrawing condensate deposited by the vapor within the condenser and injecting the deposited condensate into the vapor flow path.

The invention also includes the method of regulating the temperature of superheated vapor which comprises passing a stream of vapor from a vapor generator through a superheater, creating a pressure drop at a location in the vapor flow path, condensing vapor from the vapor generator and entraining condensate in the vapor stream by supplying the entrained condensate at least partly at the said location and varying the rate of supply of entrained condensate in order to regulate the temperature of superheat.

The invention will now be described by way of example with reference to the accompanying schematic drawings representing a number of elements of a marine water tube boiler provided with a superheat regulator.

In the drawings:

Fig. 1 of the drawings is an elevation illustrating the apparatus from a side of the boiler; and

Fig. 2 is a front elevation.

Referring to the drawings, in the upper part of a marine boiler a steam and water drum I having its longtiudinal axis extending from front to rear of the boiler is suitably arranged in a usual manner for the reception of a steam and water mixture from banks of steam generating tubes IA and IB suitably arranged below the drum within the boiler casing 2 and heated bygases from a furnace (not shown) also situated within the boiler casing below the drum. Between the banks of the steam generating tubes,

superheater tubes (not shown) are arranged for heating by the furnace gases. Within the boiler casing and at one side of the drum an economizer 3 is disposed, arranged for the reception of heat from furnace gases after they have yielded heat to the boiler and uperheater tubes.

The steam and water drum 1 is provided towards the front end thereof with a drum steam outlet 4 connected to the uppermost part of the drum and communicating with the steam inlet 5 of acondensing chamber 6. The condensing chamber 6 has a length about half that of the steam and water drum I and a diameter about one quarter that of the drum and is arranged horizontally at about the level of the top of the steam and water drum.

The condensing chamber is so formed that one end 1 is closed and at the other end a flange 8 is provided for the securement of a tube plate 9 and associated divided distributing head 10. Extending into the chamber from the tube plate is a bundle of U-shaped condensing tubes indi-'- cated at I], the respective ends of which communicate with an inlet compartment lit in the divided distributing head to which condensing water may be supplied through a water inlet 13 and with an outlet compartment l4 in the divided distributing head from which condensing Water may be Withdrawn through a water outlet I 5.

The withdrawal connection I8 is provided with a valve indicated by 20 for the control, of the flow of condensing water through the condensing tubes ll.

The condensing chamber is arranged with its flanged end towards the front of the boiler and its closed-end towards the rear of the boiler.

The steam inlet 5 of the condensing chamber is provided adjacent the front end thereof. and a steam outlet 2| from the condensing chamber is nel therethrough decreases gradually. in Jthe'.

manner of a Venturi nozzle from eachend of the pipe section to a throatfbr positionlofmaxi mum constriction indicated at 29 nearlyI e'qui distant from the ends.

(or thermal liner) of the Connecting with the' I 4 densing chamber, the danger of water hammer is avoided.

Should the quantity of water in the condensing chamber reach an abnormal value such as to cause a sufficiently high water level at the position of the emergency drain 30, water will flow from the condensing chamber through the pipe 3| and drain inlet 32 and Will'be discharged through the discharge end 33 into the water in the steam and water drum.

Whatis claimedis 1. In" a vapor generator, a vapor and liquid drum, a superheater means including a conduitproviding'for theflow of vapor from the drum bottom of the condensing chamb'er' 6 near thi'e rear end thereof is a drain 25 connected to a' water pipe 26 arranged to lead condensate water to a water inlet 21 which discharges the condensate intothesteam flow through an orifice 28in the allo'f the throat29i? any i bertisjprovided'with an emergency drain 31) lea'ding from'a'side of the chamber and con-' rg td th'ough a pipe 3| with a rain inlet 32' 7 through the wall of the steam and water drum and arranged, with its" discharge" end 33' below. a i'armai water level Qinth drum."

F r the automatic regulation of superheated steam tern ratur t e' noworre eu water through the c;6 a e mg" ciiainberg n parallel withf'the I j through th'ej'economizer,is arranged tobe' aut matical y" egained by control or the valve 29 accordance j'withthe fsteafn" temper= a j Such automatic. I I ltijnst'au "n tne si1perheateroutlet header. 'ther ostat directlyactuatefs' the"valve volumetric 'chfaiiges'of' ajvo'latile liqt e'th' r'r'iostatandapipeconnection 4| heijthermostait'to the valve2lil' During'the' of the boiler; saturated steam flows from "the" steam"and Water drum through the steam outlet 4 and steam inlet 5' into the coniiigpharnber'fiywithin which steam is conden densed in'an amount depending upon therate offiow of water in the condensing tubes II.

some of the condensate is carried in suspensi'on by the steam leaving the condensing chamber"through the steam outlet2 I, but a proportion of the condensate falls to the bottom of the con- 'at' the una-or the superheaterf u m i operation (lensing chamber from which it is withdrawn bythe drain and, under the influence of reduced steam pressure at' the throat 29 of the Venturi nozzle within] the pipe section 212 isc'onducted by the pipe 26 and-inlet 21 and injected through the orifice 28 into thesteam-flowwithint the pipe section 22. The condensate enters the steam channel as a spray and is entrained bythe'steam. The steam pressure lostat the throat 29 issubstantially-re'gainedin thesteam duringits flow to the outletend of thelpipe section '22. g, V

. Control, of the valve 20. and therefore of the rate. of. flow ojnrwaterflin the condensing t1 bes Ll. operates" .to vary theflwetnessm oi the steam led tothe .superheater ;and the temperature of sup er 'densate formed at any moment is quickly; carried awaywby the steam, an ef ec ve cont o of t temperature. .of superhe t. v s. Obt i ed a d ir e condensate is continuously drained from the conesteem may involve" a" thermostat 7 to the superheater, a vapor condenser disposed in the" vapor flow path from the drum to thesuperheater, means supplying a controlled amount of cooling fluid to the condenser, said conduit having a Venturi therein, the Venturi normally creating a pressure drop at one position in said conduit and a tubular connection between the condensate space-f of the condenser and the position of said pressure drop at the throat of the Venturi whereby condensate'fiows to the venturi and is mixed with thevapor pass ing throughthe venturi. I I I I a 2, In QK YaPQI generator; a vapor and liquid drum; asuperheater including an inlet hea er means including a conduit providing for the flow of vapor from the drumto the superheater inlet header, a vapor condenser disposed in t lie vapo r flow path from'the drum to the superheater header, means I supplying a controlled amount of cooling fluid 'to' the condenser, said conduit'hav-I ing a Venturi normally creating apressure dro'p ata position in the conduit, and a tubular cone nection between the condensate space-of thei condenser and the position of said pressure drop at'the throat of the venturi'whereby condensate; flo'wstothe 'venturi and is mixed with the vapor passing through the VBntllIi.

3. In a vapor generator, a vapor and liquid drum, a superheater including an inlet header V meansincluding a single conduit providing for the fi'ow' of vapor from the drum to the superheater inletjheader, a vapor condenser disposed in the vapor flow, path' from the drum to the superheater, means supplying a controlled limiting the level of the condensate in the con denser. V

CEDRIC HAROLD SPARKSh I REFERENCES CITED I The following references are of record in the" file of this patent:

UNITED STATES PATENTS" Number Name w Date,v .v

544,652 Bachma'net a1 Aug; 2c; 1895' 2,063,441 Kerr Dec. 8;1936 2,207,646 Van der Ploeg J y- 9;,1-940 $276,055 Ma'stenbro'ok' Mar. 19119 2303146" Thompson Nov. 24;"1e'42j 2,319,223 Frisch May 18, 1943*

Images