US1541519A - Feed-water heater - Google Patents

Description

N. T. MCKEE FEED WATER HEATER.

Filed Oct. 3, 1923 2 Sheets-Sheet 1 O @@CO) ooo t O I\ N INI/EIVTB /VEHL 7 /VC/(EE ATTUR/VEYS June. 9, 1925.'

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4 nom/frs lqI T. FEED WATER HEATER June@ 1925- Y Patented June 9., 1925.l

lUNITED STAT-Es PATENT ori-uca.

NEAL T. MOKEE, GF MOUNT VERNON, NEW YORK, ASSIGNOR T THE SUPERHEATEB COIEPANY, PF NEW YORK, 'N. `Y.,

A CORPORATION 0F DELAWARE.

FEED-WATER HEATER.

Application ld October 3, 1923. Serial No. 386,231.

To all whom it may concern:

' Be it known that I, NEAL T. MCKEE, a

citizen of the United. States of America,

have invented certain new and useful Improvements in Feed-Water Heaters, of which the following is a specification.

This invention relates to feed water heaters and more particularly to that type of feed water heaters designed for use upon steam locomotives. In this type of heater a plurality of small copper tubes are located within an outer steam casing or jacket and are suitably secured to and extended between a pair of headers, one of which is fixed to the casing at one end thereof and the other of which is freely floating at the other end, the steam 'beingadmitted to said casing to surround the tubes and heat the feed water passing therethrough.

The feed water 1s pumped under pressure into a suitable water space in the lfixed header, which .water space communicates with a lower quadrant of tubes to conduct the water to the header at the op osite end of the casing, and passes throug a water chamber in the floating header to a second quadrant of tubes immediately above the rst quadrant.'v The second quadrant of tubes leads the water back to a second water space of the fixed header which leads it to the adjacent upper or third quadrant of tubes, throu hwhich it flows back to a second water c amber-in the floatingheader, which delivers it to .a fourth quadrant of tubes from which it passes through the fixed header to a feed pipe which carries water to the boilers. v

Great ditliculty has been experienced with this type of feed water heaterm maintaining a steam tight jointv between the small copper water tubes andthe headers because of the unequal expansion of the tubes, it being obvious that the water within each quadrant of tubes is at a different temperature, consequently a twisting strain is produced uponY the Hoating header, this strain being at a maximum between the first and fourth quadrants. lin order to overcome this vtwlsting strain due to the differences in expan-- sion caused by the unequal tem eratures in each quadrant, the oating `hea er has been divided vertically 4into two equal` halves each of which is connected with one-half of the total number of tubes, one halfheader thus formed being connected with the first and second quadrants of the tubes and the other half-header being connected with the third and fourth quadrants. While this expedient has Vresulted in decreasing to a certain extent the twisting strain upon the ioating headers and the loosening of the tubes due to unequal expansions, it has not altogether overcome the loosening of the tubes, as a further loosening thereof is caused by tension produced upon the tubes b unbalanced water pressure vwithin the eaders, tending to cause said headers to move away from each other longitudinally of the tubes.

The principal object of this invention is to provide a new and improved construction in a feed waterheater of the type described by means of which'jthe tension upon the .tubes due to unbalanced water pressures within the headers 1s removed.

For the accomplishment of these and such further objects as will hereinafter be apparent to those skilled in the art to which this appertains, the invention consists in the construction, combination and arrangement of parts, a preferred embodiment of which is hereinafter specifically described and is illustrated in the accompanying drawing, but it ,is to be understood thatchanges, variations and modifications ma be resorted to without departing from t e spirit of my invention. In the drawingI forming a portion of this specification and wherein like reference characters designate corresponding parts throughout the several views,

Fig. 1 is a side elevation partly in section of a feed water heater of the type disclosed and embodying my invention;

Fig. 2 is a section on the line 2 2 of Fig. l;

i Fig. 3 is.,A a section on the line 3 3` of which the xed header 11 is secured. lSuitably secured to the header 11 and extending longitudinally within the casing are a plurality of small c per water tubes 12, the other end of which) tub-es are secured to a pair of Hoating half headers 13 as heretoitore described. The header 11V is provided with suitable dividing walls to direct the water from the inlet pipe 14 through the first quadrant of tubes to the floating half header 13 shown at the right of Fig.v 2, passing upwards through water chamber 15 of said header to the second quadrant of tubes, back to header 11, thence horizontally through water chamber ltthereotI to the third quadrant of tubes upon the left hand side (Fig. 2) of the heater. The water then passes through the third quadrant of tubes to the upper part of the water chamber 15 of the left hand header 13 and downwardly therethrough to the fourth quadrant of tubes, through which it flows to an outlet pipe (not shown) in the header 11', similar to the pipe 14, to be led thereby to the boiler. y

As the water within the Water chambers is under pressure, there would, as inspection of Figs. 2 to 4 inclusive will clearly show, be an unbalanced pressure upon the outer walls of the water chambers 15, 15, in the direction of the arrow A in Fig. 4, with consequent strain upon the tubes 12, unless provision were made to, balance such pressure; this unbalanced pressure upon each of the floating half headers 13 would obviously be equal to the pressure upon an area equal to one-half of the combined cross sectional area of the tubes 12. In the particular construction shown, tension would be exerted directly upon the expanded joints 17 by means of which the tubes 12 are connected with the headers 13. In order to eliminate this tension, the following means are provided: Each of the floating half headers 13 is provided centrally thereof with a boss 18, which is provided with a bore 19, communicating directly with the Water chamber 15. The bore 19 isA screw-threaded to receivea reduced apertured boss 2O o' an inner guiding sleeve 21 provided as at 22 with suitable packing. A movable cup shaped cylinder 23 is slidably mounted upon the gulding sleeve 21 and the inner diameter of said cylinder is so proportioned that the cross sectional area of thecylinder will be equal to the combined cross sectional area of the tubes connected to its respective header. The end closure 24C of the outer casing is provided with a pair of bosses 25 as shown in Figs. 3 and d each of which is in alignment with the axial center of its cooperating cylinder 23 to receive the thrust of the cylinders.

The operation of the device is as follows: when the water under pressure enters the water chambers 1 5 ofthe floating headers, the water will pass through the apertured bosses 20 oi' the guiding sleeves 21 and will force the cylinders 23 outwardly into contact with the bosses 25, thelthrust of each cylinder being Acommunicated to the end closure 24C of the outer casing, from which it is transmitted through the bolts 27 to the outer casing 10, the bosses 25 thus forming means to transmit to the `casing the outwardly directed pressure exerted by the water upon the movable walls formed by the ends of the cylinders 23. Many other means for transnntting this pressure to the casing may obviously be substituted for the bosses25 without departing fromthe principles of my invention. As the main" or fixed header 11 is secured to the outer casing, it will thus be seen that the entire thrust due to the pressure of the cylinders 23 will be in eect tied to the fixed header, and as the combined area of both the cylinders 23 is equal to the combined area of all the tubes 12, that the tension due to the unbalanced pressure in the water chambers is entirely removed fromthe tubes.

While I haves'hown my invention as applied to a feed water heater having a pair of floating half headers, it will be apparent that the same principles of construction vcould be applied to a single floating header or to a heater having more than two float ing headers. i

l claim: v 1. ln a feed water heater having an outer steam casing, a main header and a floating header therein and a plurality of water tubes secured to and extending between said headers, said headers being provided with water chambers with which said tubes are in communication and means to transmit to said casing outward strains due to unbalanced water pressure within said fioating header, whereby tension upon said tubes due to such unbalanced pressure is prevented.

2. 1n a feed water heater having an outer steam casing, a main header and a floating header therein and a plurality of water tubes secured to and extending between said headers, said headers being provided with water chambers with which said tubes are in communication., and means defining a chamber secured to said ioating header and communicating with the water chamber thereof, a movable wall Within said chamber having a cross sectional area approximately equal to the combined cross sectional area of the water tubes connected with said header, and means to transmit the outwardly directed pressure upon said movable wall to said outer steam casing whereby tension upon said water tubes due to unbalanced pressure within 'said floating header is prevented.

3. ln a feed water heater having an outer lll@ steam casing, a main header and a oating header thereinV and a plurality of water tubes secured to and extending between said headers, said headers being provided with water chambers with which said tubes are in communication, a guiding sleeve secured to said Hoating header, a cylinder having a closed outer wall slidably mounted on said sleeve and defining with said sleeve a chamber communicating with the water space of its respective floating header, the inner face of said 'closed outer wall being approximately equal to the combined cross sectional area of the water tubes connected with said floating header and means to transmit the outwardly directed pressure upon said closed outer wall to said outer steam casing whereby tension upon said water tubes due to unbalanced pressure within said header is prevented.

4. In a feed water heater having an outer steam casing, a main header secured to said casing, a plurality of oating headers and a plurality of water tubes secured to and extending between each of said floatin headers and said main header, each of sai headers being provided with a water space with which said tubes are in communication and means defining a chamber secured to each of said floating headers and communicating with the water space thereof, a movable wall of each of said chambers having l a cross sectional area approximately lequal to the combined cross sectional area ofthe `water tubes connected to its respective oating header, and means to transmit the outwardly directed water pressure upon said movable wall to 'said outer steam casing whereby tension upon said water tubes due to unbalanced pressure is prevented.

5. In a feed water heater having an outer steam casing, a main header secured to said casing, a plurality of floating headers and a plurality of water tubes secured to and extending between each of said Heating headers and said main header, each of said headers being provided with a water space with which said tubes are in communication', a guiding sleeve secured to each of said floating headers, a cylinder having a closed outer end wall slidably .mounted on said sleeve and defining with said sleeve a chamber communicating with lthe water space of its respective oating header, the

inner face of said closed outer wall being approximately equal to the combined cross sectional area of the water tubes connected to its respective oating header and means to transmit the outwardly directed pressure upon the inner face of said closed outer wall to said outer steam casing whereby tension upon said water tubes due to unbalanced pressure is prevented.'

NEAL T. MOKEE.

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