US2229136A - Supplying superheated steam to locomotive engine cylinders - Google Patents

Description

Jam 21, 1941' E. L. scHELLENs 2,229,136

SQPPLYING SUPERHEATED STEAM TG LOCOMOTIVE ENGINE CYLINDERS Filed June 2, 1957 s sheets-sheet 1 4*- l/a ms Jal 21, 1941'v E. l.. scHELLENs Y 2,229,136

SUPPLYING SUPERHEATED STEAM TO LOCOMOTIVE ENGINE GYLINDERS Filed June 2, 1937 5 sheets-Sheet 2 Jan. 21, 1941. E. l.. scHELLENs SUPXLYING SUPERHEATED STEAM T0 LOCOMOTIVE ENGINE CYLINDERS 3 Sheets-Sheet 3 L.. SM. HL?? Filed June 2, 1937 Patented Jan. 21, 1941 UNITED STATES SUPPLYING SUPERHEATED STEAM TO LOCOMOT'IVE ENGINE CYLINDERS Eugene L. Schellens, Ridgewood, N. J., assignor to C--S Engineering Company, Englewood, N. J.,

a corporation of Delaware Application June 2, 1937, Serial No. 145,921

9 claims.

This invention relates to locomotives and to apparatus for superheating the steam and for conducting the superheated steam to the engine cylinders.

One of the objects of the present invention is the provision of a superheater unit adapted to be positioned within a fire tube or' gas flue of the locomotive boiler and so constructed and arranged as to have high heating efficiency and low steam resistance and also to oier low resistance to the ow of combustion gases through the re tube.

The usual type of superheater unitcomprises a plurality of return-bend tubes rthrough the long passes of which the steam ows in series and in opposite directions and alternately counter to and withthe iiow of gases in the re tube. In such a superheater unit the tube passes wherein the steam flows in the direction of ow of gas are relatively inefficient in transferring heat to the steam from the combustion gases'as compared with the heat transfer in the counter-flow passes of the superheater unit. Such a superheater unit also has a relatively high vdrop in steam pressure between its inlet and outlet ends.

Hence a further object of the invention is an improved form of superheater unit having a relatively large number cf tube passes in which the steam flowscounter to the flow of vgas and a small number 'of tube passes, and preferably'one tube pass of large diameter in which the steam flows with the flow of gas so that the unit has high thermal efficiency 'and also large steam area whereby the drop in pressure between the inlet and outlet cf the unit is low. n

A furtherebject of the invention is the prolvision of a superheater unit consisting of a plurality of small tubes connected in parallel to a common manifold and surrounding a large return tube toj which the small tubes are connected at the Yends-remote from the manifold, the large return tube passing through thev manifold and being free from rigid connection therewith so as to perinit relativeexpansion and contraction movement between the small tubes and the return tube.

In the superheater embodying the kpresent invention there is provided a saturated steam headhaving a plurality of depending branch headers. 'There is also provided a superheated steam header having a plurality of branch headers. In accordance with the present invention ythe superheated steam headers and the saturated steam headers are tapered in opposite directions and are free from rigid interconnections and a vertical group Aof superheater .units are connected with a saturated and a superheated steam 4header in such a Way 'that the sameireedom for expansion and contraction movement toward and away from the front tube sheet of the boiler is permitted at any one of the superheater units. Such a construction constitutes a further object ofthe in- A 5l vention.

Another object of the invention isv the provision of superheated and saturated steam branchhead- `ers that are arranged one lbehind the other in line witha vertical bank of fire tubes andthe 10 superheater units therein, the superheater unit having a saturated steam manifold provided with an entrance tube which is disposed suniciently at one side of the saturated steam headersowthat it can be connected therewith with but. a' single 15 bend, the superheated steam outlet oi the unit being in axial line with. the superheated steam branch header so that it can be connected with the branch header by a tube having but one bend therein. Ink the usual superheater constructionlthe ,superheater units are connected with the saturated and superheatedsteam headers througha large number of connections that by reason of4 space limitations cannot be securedV together sufcient- .20 ly strongly to surely prevent steam leakageand as a consequence one of the' objections to this'type of superheater is the leakage of steam into vthe smoke box and the resultant clogging offthe smoke box screening.` It is an object of the presentinvention to provide a superheater construction wherein the superheater units .are .connected to the headers through b-ut a relatively small number .ofy joints which are spaced apart suiciently vto permit the 3.5 use of clamping flanges and bolts of. ample size. Another object of the invention is the provision -of a superheater unit comprising a series of tubes `.plurality of tubes welded or otherwise secured to 45 ythe smoke box shell andupstanding therein and .receiving branch headers at their upper ends and opening at their lower ends into a main header that is disposed on the outside of the smo-ke box shell. l f 50 rlhe main superheater header is disposed transversely of the smoke box shell and at its Opposite -ends is provided with throttle valves and separate steam connections from l.thethrottle valves to the locomotive cylinders. 'Ilhis arrangement v 55 places the throttle valves desirably close to the cylinders and permits the use of a separate throttle valve for each cylinder and constitutes a further object of the invention.

Another object of the invention is the provision of improved operating mechanism for the throttle valves so arranged that they are caused to be opened by approximately the same amounts and to be surely closed, the operating mechanism including equalizing mechanism that is interposed between the Valves and the throttle lever in the locomotive cab, the mechanism being disposed beneath the locomotive boiler. While it has been proposed heretofore to provide a locomotive with a throttle valve for each of its two cylinders, the valves being located outside of the locomotive shell in separate pipes that passed into the shell, the operating mechanism for the valves necessarily was constrained to pass through the smoke box where it was liable to become fouled and rendered inoperative by the cnders and dust therein. This objection is obviated by the present construction.

A further object is generally to improve the vconstruction and operation of devices for superheating the steam and for conducting the superheated steam to the cylinders of a locomotive.

Fig. 1 is a side elevatio-n of a locomotive em- -bodying the present invention and illustrating particularly the vindividual throttle valve and steam connections between the superheated steam header and the engine cylinder.

Fig. 2 is a sectional view taken along line 2 2 of Fig. 1 and illustrating particularly a iront elevation of the front tube sheet and superheater headers of the locomotive.

Fig. 3 is a sectional detail taken along line 3--3 of Fig. 2.

Fig. 4 is a plan detail of the inner end of a superheater unit.

Fig. 5 is a sectional detail taken along line 5-5 of Fig. 6.

Fig. 6 is an end View of the structure of Fig. 4.

Fig. 7 is a sectional detail of the outer end of a superheater unit taken along line 'l-l of Fig.` 2.

Fig. 8 is an end view of the saturated steam manifold of Fig. '7, taken along line 8--8 of Fig. 7.

Fig. 9 is a rear view of one of the throttle valves illustrated in Fig. 2.

Fig. 10 is a sectional View of a throttle valve taken along line IU--I of Fig. 2.

Fig. 11 is a sectional detail taken along line II-II of Fig. 10.

Fig. 12 is a plan view of the equalizing mechanism illustrated in Fig. 2.

Fig. 13 is a side elevation of the equalizing mechanism.

Fig. 14 is a section taken along line l 1 -i4 of Fig. 13.

As shown especially in, Fig. 3 the locomotive comprises a boiler having the boiler shell I6, the smoke box shell I8 and the front tube sheet 2D. A plurality of large iire tubes 22 extend rearwardly from the front tube sheet 20-and are adapted Ato receive superheater units. A plurality of smaller re tubes 24 are also extended rearwardly from the front tube sheet. Saturated steam passes through the dry pipe 26 into the `neck 28 of a saturated steam header` 30 which is disposed transversely of the smoke box shell in front of the tube sheet 20 and above the nre tubes 22. While the saturated steam header 3) can be oi' any suitable construction it preferably is a fabricated construction consisting oi a steel tube 32, the ends of which are closed by plugs 34 welded thereto, the tube being welded to the cast inlet neck 28 and having a plurality of apertured bosses 36 opening into the interior of the tube welded to the under side and extended in the line of the tube 32 and providing for a plurality of branch headers 38.

The branch headers are p-rovided at their upper ends with attaching ilanges 48 through which clamping bolts 42 are passed and are screwthreaded into the bosses 36. A seating disc or ywasher 44 is clamped between the at face of the flange 40 and a conical seat of a boss 35 to insure a steam tight joint therebetween. The joint between the branch header 38 and the main header can be depended upon to maintain itself steam tight by reason of the large bolts 42 which the construction permits.

The branch header 38 tapers in a progressive manner from a large diameter at the upper end to a small diameter at the lower end thereof, the taper being for the purpose not only of providing accommodation for the diierent volumes of steam in diierent parts of the header but also to render the header flexible to permit lateral bending thereof. The large re tubes 22 are disposed in vertical lines and the branch headers 38 are disposed in front of and in line with the different vertical groups of the re tubes.

The superheated branch steam headers 46 are similar in construction to the saturated steam branch headers `38 and are disposed behind said headers 'and in line with the Vertical groups of fire tubes, the two sets of branch headers being close to each other but free from any interconnection that would tend to hinder the free lateral deection of the headers due to heating and expansion of the superheater units connected therewith. The branch headers 46 are connected through nanges 48 land 50 and the interposed sealing washers 52 and bolts 54 with the upper ends of vertical tubes 56, the lower ends of which are located in openings of the smoke box shell I8 and are secured as welded thereto. The tubes 56 are of different lengths and have their upper ends in the same horizontal plane. A superheated steam header 58, general-ly U- shaped in cross-section and open at its upper end, is welded or otherwise secured in 'a steamtight manner to the outer face of the smoke box tube i8 about the openings of the tubes 56 an'd receives the superheated steam discharged from said tubes.

The superheated steam header 5B extends transversely of and under the smoke box shell I8 and at its opposite ends is provided with steam take-off ears 60, in each of which a throt- `tle valve is located. The construction of a takeoff ear is illustrated more particularly in Fig. 10. As shown in this iigure the parallel opposite side walls 62 of tlhe head-er have coaxial openings in one of which Ia coupling member 64 is seated and is secured thereto by bolts 66 and in the other of which a lcylinder' member 68 is seated arid is secured thereto by bolts 10. A pipe 'l2 yconnects each coupling member with adjacent locomotive cylinders, las is illustrated in Fig. 1.

A throttle valve seat member T4 is carried by the couplingr member and 'cooperates with =a throttle Valve 1G. Said throttle valve has a hollow Istem 18 that at its other end carries a piston 80 reciprocable in the ycylinder member 6'8. A valve rod 82 passesthrough the Valve stem 'I3 and yaxially slotted bushings 84 therein and covoperates the piston 8|) `tosupport..the thrott'le valve 'for kmovements toward and .away from its seat. The valve stem v82 is loosely guided for longitudinal movement in the hub of the valve seat member 14. The valve stem 82 is provided with a pilot valve 88 a'd-apted to open and close `the passage through the valve stem 18. 'Ilhe valve stem is lalso provided with an abutment 92 which is engageable with the throttle valve to move it away from its seat.

The chamber 94 of the cylinder member B8 is pressure tight land the piston 80 has a small amount of leakage between its opposite ends from the interior of the .superheated steam lhead-er into the :chamber 94 either by reason of the clearance between .the piston 80 an-d the lcylinder member or by reason of a leakage passage 96 through the piston. The .throttle valve 16 is slightly larger in diameter than the piston 80 so that the steam pressure acting thereon in the superheated steam header tends to bias the valve for movement into closed posi-tion. When the valve is closed the chamber 94 is under the pressure of steam in the :superheated steam header and hence the valve is maintained positively closed. Movement of the pilot valve 88 away from its seat on the piston 80 serves to relieve the pressure in .the chamber 94 .so that the throttle valve can be opened readily when the valve 'stem 82 has been moved sufficiently to bring the abutment 92 against the throttle valve.

The throttle valve is operated by a shaft 98 which passes through a packing gland |00 into the chamber 94 and thas an arm |02 fixed thereto .and extended therea'bove and pivotally connected with a pair of links |04 that are pivotally yconnected tothe valve stem 8i2.

The throttle valves in the opposite ends of the superheated steam header are interconnected for conjoint operation through equaliaing mechanism illustrated in Figs. 2, 12, 13 and 14. The two operating shafts 98 for the two throttles 4are exten'ded parallel with the superhea'ter header and transversely under the locomotive boiler and in axial alignment and are terminated in hubs |06 and |01 which are journalled in a supporting bracket .tl 0 secured by suitable means M2, Fig. 1, to the under side of the locomotive boiler shell. The tfwo hubs are provided with closely con-fronting annular flanges |`|4 and IIB. The flange ||4 has a plurality of outstanding pins `||8 which are passed loosely through openings |20 in the flange |16, the openings being sufficiently greater in ydiameter than the diameter of the pins to permit sufficient relative axial movement between the valve operating shafts 98 to insure the positive closing of both valves irrespective of small play between the shafts and the valves or differences in the settings of the valves.

fIhe operating shafts 98 have equaliaing arms |.2`=2 'and |=24 xed thereto and extending in the same direction and terminated in pins |26 passed loosely through an equalizing bar |28 having a cylindrical mid portion |30 on which a bushing |32 is journalled. A yoke |34 has a pair of arms |36 which embrace the bushing `|l312 and are provided vvith pins |38 that are journalled in the bushing and thereby provid-e a universal connection between the yoke and the equalizing bar. The other end of the yoke is pivoted at |40 to the end of an arm |4l2 fixed to a sho-rt shaft |44 journalled in the bracket ||0 `and having an arm |46 fixed thereto which i's adapted for iconnecltion through linkage |48, see Fig. `l, with the throttle lever |50 in the engine cab.

The arrangement is such that a pull or a thruston the equalizing bar through the yoke |34 effects the rotation of one shaft until the clearance between the pin H8 and the side wall of the opening' in which it is located is taken up and then effects the rotation of both shafts with the consequent movements of both throttle valves. When, however, the valves are moved into closed position the setting of one valve upon its sea-t causes the equalizing bar to fulcrum upon the arm |22 or |24 associated with that valve to cause the movement of the other valve against its seat. Hence with this construction herein provided both throttle valves are caused to be surely seated.

With the throttle valve arrangement herein -shown the connections between the superheated steam header and the engine cylinders are short and direct and entirely outside the smoke box and the throttle valve operating mechanism is not exposed to smoke box conditions that would tend to render it inoperative.

The present construction represents a saving of several hundred pounds of weight over the usual construction wherein a pair vof steam pipes run from the top of the smoke box through the shell thereof to the engine cylinders.v This saving in weight is highly important in the design of locomotives that'otherwise are up to their limit of Weight as the weight saved by the present construction can be used advantageously tothicken the boiler shell and use increased steam pressure, for instance, thereby to render the locomotive more powerful and eicient.

The saturated and superheated steam headers are connected by a plurality of superheater units contained within the large fire tubes 22. The units are more or less identical in construction. Each unit comprises an annular spaced cluster of small parallel tubes |52 surrounding and radially spaced from a large return tube |54, see Figs. 2 through 8. The'small tubes |52 receive saturated steam from a generally cylindrical casting or manifold |56 located close in front of the front tube sheet and having a conical front wall |58 which confronts the open ends of the fire tubes and serves to deflect away from the manifold dust and cinders that pass through the fire tube and might otherwise lodge on the manifold. The front ends of the small tubes |52 are located in openings in the conical front wall of the manifold and are welded or otherwise secured in a steam tight manner therein. rIhe manifold |56 is provided with a centrally located tube |68 which passes through the front conical wall |53 and also the radial back wall |62 and is welded to both walls in a steam tight manner. The return tube |54 passes looselythrough said tube |50 and hence thetube and the manifold are free for relative axial movements to permit expansion and contraction of the tubes of the unit.

The inner end of the return tube |54 is closed by va plug |64 and forwardly of the plug is provided with four equiangularly spaced slots |68. Hollow ears |58 are welded to the tube |54 over the slots |66 so that the slots communicate with the chambers in the ears. Said ears |58 at the Vends and opposite sides thereof are provided with the common return tube |54. This described arrangement permits a ready assembly of the unit and provides for a relatively free gas flow around and lengthwise of the various tubes. The forward ends of the various ears |68 and |12 are curved or stream-lined to facilitate the flow of gas about them.

The projecting forward ends |54a of the return tubes |54 of the tube units are disposed in line with a superheated steam branch header 46 and are bent downwardly as is indicated in Fig. 3, and are welded or otherwise secured to the branch header, the downward bend of the tubes being for the purpose of facilitating the entrance of the superheated steam into the entrance of the superheated steam header. By having the large return tubes in the line of the header the connection therewith can be made by but a single 'Ihe saturated steam manifolds |56 are provided with ears |14 which are extended all in the same direction and project beyond the lines of the sets of branch headers. Each ear is provided with an opening into which a saturated steam inlet 4tube |16 is secured, the pipe lying at one side of the branch header with which it is associated and being provided with a single and upward bend where it is joined with the branch header, the projecting ears |14 obviating the necessity for complicated double bends in the inlet tube that would be necessary otherwise.

All of the superheater units of a vertical row of nre tubes 22 are permanently connected to their associated pair of saturated and super-` heated steam branch headers and are adapted to be removed as a unit with the branch headers upon the removal of the bolts 42 and 54 which connect the branch headers with their respective main headers. The pairs of saturated and superheated steam branch headers are free from rigid interconnections and hence can flex laterally to accommodate the expansion and contraction of the tubes of the superheater units. By having the branch headers tapered, and tapered in opposite directions, the conjoint lateral deflection of the pair of headers is the same anywhere along the length of the headers and is designed to be sufcient to accommodate the maximum change in length of the tubes of the unit under the normal operating conditions.

I claim:

1. In a locomotive in combination with its boiler shell, steam superheating apparatus inl cluding a plurality of separate tubes secured to and carried by and upstanding from the interior of said shell and opening through said shell, superheater units connected with said tubes within said shell, and a superheated steam header independent of said tubes carried transversely by said shell externally thereof and encompassing the tube openings through the shell.

2. Superheater apparatus for locomotives comprising an upper saturated steam header located within and transversely of the locomotive shell and having a plurality of saturated steam outlets disposed in line at the bottom part of the header, a lower superheated steam header extended transversely of the locomotive shell including means providing a plurality of superheated steam inlets arranged in line transversely of the boiler shell and at one side of the line of said saturated steam outlets, vertical branch headers having means detachably securing them to said inlets and outlets, said branch headers being arranged in pairs and extended in opposite directions from -their associated main headers and each being integral and tapered from end to end and being free from rigid interconnection with each other except at their interconnections with their respective main headers, and a plurality of superheater units disposed in vertical lines having inlet tubes welded to a common saturated steam branch header, and outlet tubes welded to a common superheated steam branch header, said inlet and outlet tubes being free for relative .expansion movement and the branch headers connected to any one superheater unit being capable of lateral flexure of different amounts in the line of such unit to accommodate such movement.

3. superheater apparatus for locomotives comprising an upper saturated steam header located within and transversely of the locomotive shell and having a plurality of saturated steam outlets disposed in line transversely of the shell at the bottom part of the header, a lower superheated steam header extended transversely of the locomotive shell including means providing a plurality of superheated steam inlets arranged in line transversely of the boiler shell and at one side of the line of said saturated steam outlets, vertical branch headers having means detachably securing them to said inlets and outlets, said branch headers being arranged in pairs and extended in opposite directions from their associated main headers and each being integral and tapered from end to end and being free from rigid interconnection with each other except at their interconnections with their respective main headers, a plurality of superheater units disposed in vertical line having inlet tubes welded to a common saturated steam branch header, and outlet tubes welded to a common superheated steam branch header, said inlet and outlet tubes being free for relative expansion movement and said branch headers being independently capable of lateral exure to accommodate such movement, the associated saturated and superheated steam branch headers being arranged in line with the associated superheater units and one branch header behind and spaced from the other branch header.

4. In a superheater apparatus for locomotives, the combination of removable superheated and saturated steam branch headers and a superheater unit connected therewith, said headers being arranged in the axial line of said superheater unit and one header behind and spaced from the other header, said superheater unit having an outlet tube which is in the axial line of the superheater unit and headers and is welded to the nearest header, said unit also having an inlet tube which is at one side of and parallel with the axis of the unit and passes by the near header and has an end part which is curved upwardly and is welded to the side of the remote header opposite the near header.

5. In superheater apparatus for locomotives, a saturated steam header, a superheated steam header, a superheater unit, said headers being arranged in the axial line of said unit and one header behind the other, the superheater header being nearest the superheater unit, said superheater unit including a manifold, a plurality of superheater tubes connected with said manifold, said manifold having a steam inlet located at one side of the line of said headers and a steam inlet tube connected with said inlet and passing beside said superheated steam header and having an end part curved upwardly and welded to said saturated steam header on .the side opposite said superheater branch header, said superheater unit having a common superheated steam return tube connected with the aforesaid superheater tubes and disposed in the line of said superheated steam header and having a welded connection therewith.

6. A superheater unit for locomotives adapted for insertion in a fire tube thereof including a common return tube, an annular saturated steam manifold having a sliding connection with said tube at the outer end thereof and having a front wall and a conically shaped rear wall that confronts the end of .the fire tube, and a plurality of superheater tubes surrounding and extended lengthwise of said return tube and having conneotions with the interior of said manifold through said conical wall and having connections with the inner end of -said return tube, said manifold having a steam inlet through its outer wall.

7. A superheater unit for locomotives including an annular series of superheater tubes, a `common return tube disposed within said series of superheater tubes, said return tube at one end having a plurality of outstanding circumferentially spaced hollow ears opening in-to the interior of said return tube, the ears being located between and each communicating Wi-th a pair of said superheater tubes, and the tubes opening into the sides of said ears.

8. A superheater unit for locomotives including an annular series of generally parallel superheater tubes, a common return tube for said superheater tube disposed within said annular series, said tube having a plurality of outstanding circumferentially spaced hollow ears opening into the interior of said tube, each of said ears having oppositely laterally projecting ears, and a pair of superheater tubes connected with said last named laterally projecting ears.

9. superheater apparatus for locomotives comprising upper and lower saturated and superheated steam main headers, the upper saturated steam header having a plurality of downwardlyfacing saturated steam outlets, and the lower superheated steam header having a plurality of upwardly facing superheated steam inlets, individual Vertical saturated steam branch headers having means detachably securing them to said outlets and extended downwardly from said satuated steam main header, individual superheated steam branch headers having means detachably securing them to said inlets and extended upwardly from said superheated steam main header, each of said branch headers being integral and tapered from one end to the other and being free from rigid interconnections with each other except through their connections with the main headers, and a vertical group of superheater units having inlet tubes welded to a common saturated steam branch header and outlet tubes welded to a common super-heated steam branch header, said inlet and outlet tubes being free for relative expansion movement and the branch headers connected to any one superheater unit being capable of lateral flexure of different amounts in the line of such unit to accommodate such movemen-t.

EUGENE L. SCI-IELLENS.

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