US1754781A - Drainage control - Google Patents

Description

April 15, 1930. J. M BARRETT 1,754,781

DRAINAGE CONTROL Filed Nov, 19, 1926 2 Sheets-Sheet 1 April 15, 1930. J. M. BARRETT DRAINAGE CONTROL Filed Nov. 19, 1926 2 Sheets-Sheet 2 Patented Apr. 15, 1930 i STATES Phil" Fl 6E .rosnrn M. ammie, or noszromn, on o, ASS-IGNQR TO THE swamwon'r contrary,

or CLEVELAND, one, A ,oonroae'r on or QHIG DRAINAGE coN'rBoL Application filed November 19, .1936.

This invention relates to power plants and is particularly concerned with the control and dispositiono-f condensate collected trom high pressure lines.

In the embodiment of invention shown herewith, I illustrate a preferred dorm of system for using and distributing condensate which is collected from high pressure steam lines. I employ a baflle chamber to be associated with the main steam header near the prime mover, so that any water which is carried to this point may be taken awaycr separated from the steam .so that no water will he carried into the prime mover. Associated with the lea-file chamber and communicating with the lowest portion thereof, I position a condensate receiver from which I withdraw the condensate accordingtothe rate at which it accumulates. It is amongithe' objects of invention to maintain a water seal in the re ceiver so that steam will not be diverted away from the steam line and at the same time to insure the adequate discharge of the condensate: so that the :bafile chamber will be kept dry and no water Will the carried over. To insure a dry ibafile chamber, it is necessary to provide means for draining the receiver rapidly in case an unusually l arge amount of water is accumulated. It is equally important to very :caretully control the flow from the receiverso that the water seal fisalways maintained.

In controlling the {low from the receiver,

a valve is employed in the discharge line,

which valve isjzopened according to the elevation of the water level an the rece ver. Now it a large enough valve s employed @to take care of an emergency, it has been found that Serial No. 149,439.

Byi the useof aplurality of valvesofdiflerent sizes, I accomplish the iurtherobjectof controlling the distribution of condensate and by this control oi? distribution I .ainable to effiectively ause no more than certain predeterminedamount ofcondensate to iheating the feed water, and I dispose oi. the occasional large amounts in a manner inost ilitting. For example, by limitingithe capacity of the small valve, I ,am able to direct a limited amount of condensate to .the feed Water heater, but 1f all ofan unusually large amount of condensate were suddenly lied to the heater, ithegreat loss of pressure between the steam header pressure andthe :heater pressure would permit the condensate :to form into a large volume of steam at such a rapid rate that the heater might bu;rst.

A furtheroloject of my invention is the provision of ,a condensate system of *the thermally controlledtype which i'szadaptah'le normally to be extremely sensitive to fine regulation but which in the case of sudden overload is immediately responsive to its action foreliininating or discharging theexcess condensate.

in the following description, reference being had to the accompanylng drawings illustrating a preferred embodiment thereof. The essential characteristics are summarized in the claims.

In the drawings, Fig. 1 is side-elevation and Fig. 2 is an end elevation of an installation of the apparatus used in my invention.

Referring particularly to Figs. 1 and 2, I show at C a bafile chamber adapted to be disposed in the high pressure line adjacent the prime mover, not shown, the object being to protect the prime mover from any water which might otherwise be carried therein to its damage. Connected at the bottom of the chamber C through the pipe 1, I provide the receiver R. The receiver is advantageously disposed at an angle from the horizontal and is connected to the baflle chamber near its upper end and is provided with a discharge outlet near its lower end. The angular disposition of the receiver has certain advantages in maintaining a seal for the outlet.

From the outlet 0, I show a discharge conduit 2, which is connected with a plurality of discharge pipes; for the sake of illustration I show two pipes 5 and 6. The pipe 5 is shown to be smaller than the pipe 6 and is disposed to lead to a feed water heater not shown. The pipe (5 being the larger of the two pipes may be directed to the hot well or water storage, and is brought into use when the pipe 5 is carrying a capacity flow both for the sake of safety and for efiicient distribution of condensate.

It will be seen however, that a plurality of leads similar to 5 and 6 could be used wherein the condensate could be selectively distributed for various purposes.

Controlling the flow through the pipes 5 and 6 are valves 7 and 8 respectively, these valves are preferably of the single seat type and are adapted to be urged to open position by the springs 15 and 16 as shown. Mounted on the valve casings are frame members 17 and 18 for supporting the springs and for carrying and providing diaphragm chambers 19 and 20 respectively.

Communicating with the u aper part of the baffie chamber at point 40, I show the conduit 41 with the valve 42, the conduit leading downwardly to the valve 10, then through the connecting portion 3 to the discharge pipe 2. At 4 I show the blowotf valve by means of which the contents of the conduit 41 may be discharged. The conduit 41 is positioned to drain from the point 40 into the discharge pipe 2. That portion of the conduit 41 within the horizontal limits of the receiver R is positioned at an incline to the horizontal as shown. I have found it advantageous to incline the conduit at about twice the angle of the inclination of the receiver. The scheme of connection of the conduit 41 relative to chamber C and the discharge pipe. is shown in my copending application for Drainage control system, Serial No. 144,815, filed October 28, 1926.

Mounted on the conduit 41 at points within the horizontal limits of the receiver, as shown in Fig. 1 are pressure generators 50, 51 and 52. These generators are an improved type of those generally shown in patent to Copley, No. 1,193,125, issued August 21st, 1916. Briefly each of the pressure generators comprises a cylindrical body lying concentric with the conduit 41, in which a volatile and expansible fluid is stored. This fluid is heated and put under pressure in accordance with the rate of heat input depending upon the nature of the contents of the conduit 41 at the point adjacent the generator. Thus when the conduit contains steam the generator is heated and pressure created, and when the conduit contains water the generator is cooled with the aid of external radiating means as shown. The generator 50 is shown with expansible heads 55 and 5G and which may be brazed or suitably mounted on the conduit. A filling plug 57 is provided, heat radiating fins are shown at 58 to aid in the cooling of the working fluid. The generators 51 and 52 may be of the same general nature but of different sizes as shown in Fig.

1. The size of the generator depends upon the work demanded of the working fluid as will presently appear. The generator 50 has connected to it the conduit 31 leading to the diaphragm chamber 19 of the valve 7. The generator 52 (being the larger) is shown connected by the conduit 32 to the larger diaphragm chamber 20 of the larger valve 8. The generator 52 is connected with the conduit 60 to the pressure actuated alarm dc vice 61, which is maintained silent by pres sure transmitted to it through the conduit 60.

From the foregoing it will be seen that when there is no condensate in the receiver, that all of the generators will be heated by the presence of steam in the conduit 41, that pressure will be exerted in the diaphragn'i chambers 19 and 20, and that both the valves 7 and 8 would be held in closed position. As the condensate collects and rises the re ceiver to a level shown by the broken line NN, which I am pleased to call a normal operating level, the generator 50 will be cooled and the valve 7 forced open by the spring 15. The opening of the valve will depend upon the rate of heat exchange from 3 conduit 41 to the working fluid which in turn depends upon the water level.

At this point in the operation of my invention, I accomplish a triple object, first of accurately maintaining the water level NN and thus both keeping a water seal and keeping the chamber C dry; secondly returning hot condensate to the heater and thirdly of usually using the small valve that will not be merely cracked but will be opened wide enough to prevent wire drawing of the valve and valve seat.

If an abnormal amount of condensate be diverted from the bafile chamber to the receiver, the rate of inflow into the receiver R 11:":

in the order mentioned. level returns along the line N-N, a normal is raised beyond lthelcapacity of the valve 7 (which is limited vfOI' the purpose outlined above), the generator 51 will "be chilled and the valve8 opened. The extrad'ischarge will be handled through the pipe 6, as above mentioned and will be sent either to the hot well alarm device 61 actuated, so that manual at tention maybe given to the protection of the turbine.

After the emergency of high water has passed and as the water level in the receiver descends, the generators 52 and 51 will be heated successively as the steam moves downwardly in the conduit 41, so that the alarm device will be silenced and the valve 8 closed When the water operation is again resumed. If the water level were to descend out of contact with the generator 50, the valve 7 would be closed and the waterseal would be maintained over the receiver outlet to prevent loss of steam from the main steam header. the valve 7 is such that uniform water level will be maintained in the receiver except for w abnormalconditions as shown Elll my copene ing application above referred to.

It will. be seen from the foregoing that by the use of a plurality of valves, I :have reduced thedamage of wire drawing to a min imum and have centered substantially all of the harmful effect in the smallest and cheapestof the valves. 1 am thus able to reduce the cost of the replacement of valve members and valve seats. Along with this,by the-use of my invention, 1 am ableito control the distribution of condensate according to predetermined scheme of heat balance wherein a great saving of heat units can be effected without endangering the auxiliary apparatus. I have incorporated the control of the drainage and distribution with a system cluding the pressure generators, which are self-starting and which automatically relieve themselves of air pockets, thereby assuring a water seal in the receiver under all con, tions.

I claim:

1. A condensate return system having in combination a receiver, a plurality of pres sure generators associated therewith, discharge lines leading from "the receiver, a plurality of valves controlling the discharge lines, said valves being arranged to operate successively in said lines, a plurality of means including pressure responsive devices con- The operation of necting the valves withthe generators whereby one valve 1s operable 1n varying degrees within a range of predetermmed condensate levels in [the receiver and a second valve becomes operative within a higher range of condensate levels to increase the discharge from the receiver while the first valve is maintained in a maximum open condition.

2. A condensate return system having in combination a receiver, a plurality of then mal responsive devices associatedtherewith, a plurality of valves controlling the discharge from the receiver, said valves being arranged to open and close consecutively, a

plurality of means connectin said thermal responsive devices with the valves whereby one valve is operable in varying degrees within a predetermined range of condensate levels within the receiver and a second valve becomes operative within a hi her range of levels to increase the dischargefrom the re ceiver while the first valve is maintained in a maximum open position and an alarm device operative within a rangeof hi hest con densate levels when both of said valves are 1 wide open.

3. A condensate retunnsystem having in combination a receiver, a plurality of pressure generators associated therewith, aplin rality of valves controlling the discharge from the receiver,-said valves being-arranged to operate cor :"tivelly, a plurality of including pressure responsive devices connevzting the'valves with the generators whereby one valve is operable in varying degrees within a predetermined rangeofcondensate levels within the receiveranda second valve becomes operative within a higher range of condensate levels to increase the discharge from the receiver while the first valve is maintained in a maximum open condition.

4;. A condensate return system having in combination a receiver, a plurality of pressure generatorsassociated with the receiver, a line connecting the receiver to a feed water heater, a line connecting the receiver to a hot well, discharge valves of diflerent fluid capacities disposed in said lines and means includi pressure devices connecting the genng erators with the valves, the capacity of the valve in the line leading llO1llllQ heater being such that slight variations in the condensate level in the receiver will cause a variation in the opening of the valve whereby the valve is normally open and permits a continuous flow of condensate from the receiver to the feedwater heater while the other valve is maintained normally closed.

5. A condensate return system having in combination a receiver adapted to be connected with a high pressure, high temperature line of a power plant, drain conduits therefor, a plurality of valve means in the conduits for controlling the escape of condensate from the receiver, means associated with the valves tending to maintain them open, a plurality of pressure generator means for closing the valves and associated with the receiver at different levels, whereby one of the valves is maintained normally closed during the period in which the opening of another of the valves is being effected.

6. In a condensate return system, the combination of a condensate receiver for a steam line, drain conduits for the receiver, one of the conduits leading to a feed-water heater, a high fluid capacity valve mechanism connected in one of the drain conduits, a low capacity v'alve mechanism connected in another of the conduits, means associated with the receiver and positioned relative thereto to generate varying pressures at low condensate levels in the receiver, means connecting said generator means with the small capacity valve mechanism whereby said mechanism is acted upon to be varied tending to cause a drainage of the condensate in the receiver within the range of condensate levels to which the pressure generator means is responsive, a second pressure generator means associated with the receiver arranged to be variably active at high condensate levels in the receiver and means connecting said second named pressure generator means with the large capacity valve mechanism, whereby said mechanism is maintained normally closed during the variable activity of the first I named generator means in causing the low capacity valve mechanism to be variably active in draining the condensate from the receiver to the feed-water heater.

7. In a condensate return system, the combination of a receiver adapted to drain a high pressure high temperature steam line of a power plant, a plurality of pressure generator means associated with the receiver arranged to become consecutively active in controlling the drainage of the receiver as the condensate level therein is increased, and a plurality of valve means controlled by the respective pressure generator means. i

8. In a condensate return system, the combination of a receiver, a plurality of pressure generator means associated with the receiver and arranged to become consecutively active in controlling the drainage of the receiver 'as the condensate level therein varies and means controlled by the respective pressure generator means including valve mechanism of different capacities.

9. In a condensate return system, the combination of a receiver, a plurality of pressure generator means associated with the receiver and arranged to become consecutively active in controlling drainage of the receiver as the condensate level therein is increased, and a plurality of valve means controlled by the respective pressure generator means, one of said valve means being normally active while the other is maintained normally inactive by one of said pressure generator means.

10. In a condensate return system, the combination of a receiver, drain lines therefor, a valve in one of the lines, means tending to maintain the valve open, pressure generator means associated with the receiver and with the valve whereby pressure created in the generator tends to close the valve when the condensate level in the receiver drops, a second generator associated with the receiver at a position which corresponds to a higher condensate level therein, a second valve in another of the condensate drain lines, means connecting the last named valve and generator whereby pressure in the generator maintains the valve normally closed while the first named valve is maintained open.

11. A condensate return system having in combination a receiver adapted to be connected with a high pressure, high temperature line of a power plant, a drain conduit therefor, a pair of valves for controlling the es cape of condensate from the receiver, means associated with the valves tending to maintain them open, a pair of pressure generators associated with the receiver at different condensate levels whereby one of the valves is maintained normally closed during the period, when the amount of opening of the other valve is varied.

12. The combination of a condensate receiver, an outlet for the receiver, a plurality of discharge pipes leading from said outlet, valves in said pipes, and means for selectively controlling the distribution of condensate among the several pipes according to rate of accumulation of condensate in the receiver.

13. The combination of a condensate receiver, an outlet for the receiver, a plurality of discharge pipes leading from said outlet, valves in said pipes, and means for selectively controlling the distribution of condensate among the several pipes according to rate of accumulation of condensate in the receiver, said means including thermo-responsive elements positioned adjacent the receiver and actuable by change in water level therein.

14. The combination of a condensate receiver, and outlet for the receiver, a plurality of discharge pipes leading from said outlet, valves in said pipes, means for selectively controlling the distribution of condensate among the several pipes according to rate of accumulation of condensate in the receiver, said means including a conduit leading from the steam line passing adjacent the receiver, connected below the outlet thereof but above the said discharge valves, and thermal-responsive means for controlling said valves associated with the conduit.

15. The method of distributing condensate comprising controlling the flow of condensate through separate paths and selectively permitting the condensate to flow in the said paths according to the rate of accumulation of condensate.

16. The method of collecting and distributing condensate including collecting the condensate in a receiver, maintaining a water seal in the receiver, distributing the outflow of the receiver, first in one path and then in a plurality of paths according to the rate of accumulation of condensate in the receiver.

17. In a condensate return system, a receiver for condensate, discharge pipes for the receiver, valves in said pipes, means for varying the opening in each of said valves responsive to changes in water level in the receiver between the different zones whereby said valves are selectively actuated as the water level in the receiver rises.

18. The combination of a condensate receiver having an outlet, means for controlling the outflow of condensate from the receiver and for maintaining a water seal over the outlet of the receiver, and means acting upon said first named means for distributing the outflow from the receiver through different channels according to the quantity of condensate flowing from the receiver.

19. The combination of a condensate receiver, valve means for restricting the outflow therefrom and means controlling said valve means for distributing the outflow of condensate in different channels dependent upon the rate of outflow.

20. The combination of a condensate receiver, valve means for restricting the outflow therefrom, and means controlling said valve means for distributing the outflowing condensate in different channels dependent upon the quantity of condensate in the receiver.

21. In a condensate return system, the combination of a condensate receiver, valve means for restricting the outflow of condensate therefrom, means controlling said valve means for distributing the outflow into different paths depending on the quantity of con densate in the receiver, and means for indicating that the quantity of condensate held in the receiver exceeds a given amount.

22. The combination of a receiver for condensate, a plurality of discharge pipes for the receiver, valves in said pipes, thermo-responsive devices for actuating said valves positioned substantially above and below the normal water level of the receiver, said thermo-responsive devices being actuated in response to change in water level in the receiver whereby one of said devices controls one of said valves when the water level in the receiver is lower than normal and whereby another of said devices controls another of said valves when the water level in the receiver is higher than normal.

23. The combination of a container for steam, a receiver for condensate positioned below the container, discharge pipes leading from the receiver, valves in said pipes, tubular the zone of varying water level of the receiver and connected to said valves.

2%. A condensate return system including in combination a receiver, a plurality of discharge lines leading therefrom, valves in said lines, adjustably compressed springs tending to open said valves, pressure responsive means for closing the valves, pressure generator means connected to said last named means and associated with the receiver and responsive to change in water level therein, whereby the relation between the stresses in the said springs is a factor in determining the lag or lead between valve openings.

25. A condensate return system including in combination a receiver, a plurality of discharge valves therefor, springs tending to open said valves, means for adjustably compressing said springs, means associated with the receiver and responsive to change of con ditions therein for closing the valves against the forces of said springs, whereby the relation between the stresses in the said springs is a factor in determining the lag or lead between valve openings.

In testimony whereof, I hereunto aflix my 1;

signature.

JOSEPH M. BARRETT.

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