US2297418A

US2297418A - Valve mechanism for steam plants

Info

Publication number: US2297418A
Authority: US
Inventors: Koller Richard
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-12-05
Filing date: 1939-09-07
Publication date: 1942-09-29
Anticipated expiration: 1959-09-29

Description

Sept. 29, 1942. R. KOLLER VALVE MECHANISM FOR STEAM PLANTS Filed Sept. 7, 1939 2 Sheets-Sheet l INVENTOR Rickard K6118! BY MW ATTORN EYS p 1942- R. KOLLER 2,297,418

VALVE MECHANISM FOR STEAM PLANTS- Filed Sept. 7, 1939 2 Sheets-Sheet 2 a Q R M r o .1 l J fi m w 5 E 3 w v 3 w a \A m a m & m {m y 1 l TF R 2 w 3% m y M 3 5 m W 4 12 3 M 7 a 9 00 4 0 mm M. mm m as 5 I0:

2 w a A a 3 m ll lIlIl/l lllllllfln 1 l B 8 n a 00 1 a m1 ATTORNEYS Patented Sept. 29, ee

. 2,297,418 VALVE MECHANISM FOR srsmym'rs Richard Kiiller, Bremen, Germany: vested in the Alien Property Custodian Application September 7, 1939, Serial Germany December 5, 193

2 Claims. (Cl. 137-153) One object of the present invention is to provide new and improved means for operating and controlling the main stop valve and fuel oil valve of a power plant steam boiler, in such a way as to aflord increased safety in the operation of said plant. The invention is particularly adapted for use in ship power plants, operating under high pressure and temperature, although as far as certain aspects of the invention are concerned, it may be used in conjunction with any steam generating plant.

As a feature of the present invention, there is provided hand controlled means for operating both the fuel oil valve and the main stop valve of a boiler plant simultaneously into open or closed position.

As a further feature, means are provided for operating the main stop valve independently of the position of the hand controlled means.

As another feature, the fuel oil valve may be operated into open position independently of the position of the hand controlled means.

' As another feature, there is provided a safety device, operated by steam pressure for closing the main stop valve and the fuel valve automatically and independently of the position of the hand controlled means, when the pressure in 'the steam mains drops below a predetermined amount with respect to the boiler pressure. This construction affords additional safety means for closing the main stop valve when defects such as fractures or large leaks appear in the steam mains.

Various other objects, features and advantages of the invention will be apparent from the following particular description, and from an inspection of the accompanying drawings, in which:

Fig. 1 is a longitudinal section through one form of construction embodying the present invention, parts thereof being shown somewhat diagrammatic,

Fig. 2 is a section taken on line 2-2 of Fig. 1,

Fig. 3 is a longitudinal section of another form of construction embodying the present invention, parts thereof being shown somewhat diagrammatic,

Fig. 4 is a transverse section taken on line 4-4 of Fig. 3, and

Fig. 5 is a section taken on the line 5-5 of Fig. 3.

In the specific form of the invention shown in Figs. 1 and 2, there is provided a fuel oil valve I II for controlling the fuel to a boiler (not outlet of said boiler, and a hand controlled device I2 for operating said valves simultaneously.

The fuel oil valve I6, which may be of the slide type, is shown comprising a valve casing I6, and a valve member l6 therein, co-operating with a valve seat Il between the inlet and outlet sides of said valve, and secured to one end of a stem I8. This stem I6 is guided for axially slidable movement in a fixed guide plate 20,

and is urged upwardly in the valve closure position shown in Fig. 1 by means of a coil spring 2|, encircling said stem and seated at one end on said guide plate, and abutting at its other end a collar 22 aflixed to said stem.

The main stop valve II comprises a valve casing 25, having an inlet 26, connected to the outlet side of the boiler drum or boiler steam collector by means of a flange 21, and an outlet 28 connected to the steam mains, feeding the various prime movers of the power plant such as the steam engines. Between this inlet and outlet is a. valve member 30, adapted to co-operate with a valve seat 1 I. I

The motive means for operating the stop valve II comprises a control piston 62, reciprocable in a cylinder 33, and rigid with the valve member 36 through an interconnecting piston rod 34. The cylinder 33 is provided at opposite ends with

ports

35 and 36, having steam pressure connec- 30 tions by which the piston 32 can be moved in closure or open position of the valve .I I, according to the position of the hand controlled device I2, as will be hereinafter described.

The hand controlled device I2 includes a 35 change-over valve 39, which controls the operation of the piston 12, and which comprises a valve casing 46, and a double cone valve member 4| therein, with its two conical faces adapted to co-operate respectively with

seats

42 and 43.

This valve member H is secured to a stem 44,

having an intermediate portion 45 threaded in,

substantially of rectangular cross-section, slldabily fitted into a correspondingly shaped socket at the end of the crank shaft 46. As the handle shown), a main stop valve II connected to the 46 is rotated, the corresponding rotation of the valve stem 44 causes said stem to move axially as the result of its threaded engagement with v the valve casing 40, so that the valve member 4| is moved into seating engagement with either with the port 35 to deliver steam under boiler pressure to the upper side of the piston 32. A valve 60 in the line 51 is continuously kept in open position by a suitable plug, so that the full boiler pressure is effective through the branch connections 56 and I8.

On the other sidevof the seat 42 is a pair of ports GI and 62 on opposite sides of the valve seat 43, and in communication with each other through an intermediate valve chamber, when the valve member 4| is in seating engagement with the seat 42 as shown in Fig. l. to the port 6| is one end of a pipe 83, the other end being connected to the port 36. The other port 62 has a pipe connection 65 leading to the exhaust side of the power plant units, such as the steam engines.

When the valve member 4| of change-over valve 39 is in the position shown in Fig. 1 in engagement with the valve seat 42, the valve chamber 55 is shut off from communication with the ports 6| and 62, while said ports are in communication with each other, so that the pipe 33 is under low exhaust steam pressure. Under these conditions, the underside of the piston 32 will be under the exhaust pressure in the pipe 63, and since the upper side of the piston 33 is under boiler pressure at all times, the resultant downward steam pressure on said piston will cause said piston to move downwardly, until the valve member 30 engaging the seat 3| closes ofl flow of boiler steam to the outlet 28 and into the steam mains.

When the handle 48 is turned in a direction to move the valve member 4| to the left from the position shown in Fig. 1 into engagement with the seat 43, communication between the two ports 6| and 62 will be cut off, and the valve chamber 55 will be in communication with the port 6|. Under these conditions, the pressure on opposite sides of the piston 32 being equaliz'ed, the boiler steam pressure acting on the under side of the valve member 30 will move said member upwardly into open position to permit flow of steam through the stop valve into the steam mains.

The stop valve Il may be closed independently of the change-over valve 39. For that purpose,

there extends from the piston 32, and through one end of the cylinder 33, a rod 56, reduced in diameter at one end to form an annular shoulder 61. Loosely encircling this reduced section of the rod 66 above the shoulder 61 is a sleeve 63, which has a splined connection with a bevel gear 69, meshing with bevel pinions i0, and which is threaded to a frame structure Upon rotation of the pinions Hi, the resulting rotation of the sleeve 68 will move said sleeve axially along the reduced end of the rod 56. This sleeve 63 can be moved downwardly suil'lciently to close the valve II by the seating engagement of said sleeve 68 with the shoulder 61 of the rod 66, independently of the change-over valve 39, or

can be raised with respect to the rod 6G in posi- Connected tion to limit the extent of opening of the stop valve H.

In order to operate the fuel oil valve l3 simultaneously with the main stop valve II, the crank shaft 43 has a cam 13, desirably integral therewith, and cooperating with a lever 14, one end of which is pivotally secured at II to the frame bracket 41. This lever 14 carries intermediate its ends a roller 13, pressed into follower engagement with the cam 13 by the action of coil spring 2| acting on valve stem l3. In the position shown in Figs. 1 and 2, the high part 11 of the cam 13 being out of engagement with the follower-roller 13, the lever 14 will be in its extreme counter-clockwise position shown, so that the valve member "will be pressed into closure position against the valve seat II. when stop valve H as already described, the high portion of the cam I3 moving into engagement with the follower roller 13, rotates the lever 14 clockwise about its pivotal support, so that the valve stem I3 is pressed downwardly against the 1 action of the coil spring 2| to open the valve It.

The handle 43 is desirably provided with a device 13 for indicating open and closed position of the two valves I II and II. when the handle 43 is turned into indicated closed position shown in Figs. 1 and 2, both of these valves i3 and II will be closed, and when turned into indicated open position, both of these valves will be open.

Means are provided for holding 'the fuel valve l3 open, independently of the operation of the hand device l2. For that purpose, the free end of the lever 14 can be locked to an ear extension 13 of the frame bracket 41 by means of a locking pin 33, when said lever is rotated clockwise in position in which the fuel valve i0 is open.

In the form of the invention shown in Figs. 3 and 4, the hand device |2a for simultaneously operating the fuel oil valve la and the main stop valve comprises an elongated casing 3|, an operating handle 43a, a valve 39a for controlling the operation of the main stop valve upon operation of said handle 43a, and connecting means between said handle and said valve 39a. This valve 33a comprises a valve casing 32, and a double cone valve member 83, connected to a stem 34, and adapted to co-operate respectively with

seat members

35 and 86 on opposite sides thereof. Between the two

valve seats

85 and 83 is a port la, to which is connected pipe G3. The valve seat 85 is disposed between port Sin and a port 62a, having a pipe connection 65 to the'steam exhaust side of the prime movers,

such as the steam engines. Connected to the underside of the valve member 33 is a rod 31, having a non-conforming slide fit in the valve seat member 33 as shown in Fig. 4, to permit flow of fluid through said seat member in the position of said valve member shown in Fig. 3. Secured to the lower end of this rod 81 is a valve piston 33, which is larger in diameter than valve member 83, and which forms part of the safety means for automatically closing the stop valve upon the appearance of defects in the steam mains such as pipe fractures. Above this piston 33 is a port to which is connected pipe 53, and below said piston is a port 9| having a pipe connection 92 to the steam mains on the outlet side of the main stop valve II.

In the operation ofthe control valve 39a, when the valve member 33 is in the uppermost position shown in Fig. 3 in engagement with the upper seat 85, the ports GIa and 90 will be in communication with each other, so that the piston off. Under these conditions, the underside of the piston 32 will be under low exhaust steam pressure, so that the resultant downward steam pressure acting on said pistonwill move the valve member 30a in position to close the main stop valve II.

If anything should happen to the'steam mains such as a pipe fracture or a substantial leak, which would cause the pressure in said mains to drop below a predetermined amount, this reduction in pressure on the underside of the safety valve piston 88 will cause said piston to move downwardly from the position shown in Fig. 3, independently of the position of the handle 48a, until the valve member 83 seats on the seat member 88. In this position of the valve member 83, the stop valve II will be moved in closed position in the manner already described, and the fuel valve Illa will be closed at the same time as will be described.

The connection between the valve stem 86 and the crank handle 68a includes a crank shaft I00, affixed to said handle, and having a rotative slide connection with a collar IIlI, threaded on a sleeve I02 afl'lxed to the casing 8|. This slide connection is desirably formed by having the lower portion of said shaft of rectangular crosssection extend loosely into an aperture of corresponding cross-section in the collar IIII.

A cross-piece IE3 is threaded or otherwise secured to theupper end of the valve stem 84, and secured to the collar IN by a lost motion connection, which permits the axial downward movement of said stem by steam pressure action on the safety piston 88 as already described, independently of the position of the handle a. This lost motion connection comprises a bolt or pin I04, having its upper end secured to the collar IN, and passing loosely through the top wall of the cross-piece I03.

Stem 84 passes through a guide member I01 secured to the casing 8|, and is urged upwardly by a coil spring I08 abutting the flange of a cupshaped member I09. Extending partially in this member I09 is a sleeve nut IIII threaded to the stem 84, and having a flange seated on the flange of the member I09. The tension of the spring I08 can be adjusted by turning the sleeve nut IIO the desired extent.

Rotation of the handle 48a in one direction causes downward axial movement of the collar Illl, until said collar reaches the cross-piece I03. Further rotation of the handle 48a moves the cross-piece I03 downwardly, and in turn the stem 84 to operate the valve 39a, and close the stop valve I I as already described. Rotation of the handle in the opposite direction moves the stem 84 upwardly, and operates the valve 39a into the position shown in Fig. 3.

The fuel valve Illa includes the valve member IGa connected to the stem Hill, which is urged upwardly by means of the coil spring 2Ia. A

lever 14a pivotally supported at II2 has one forked end engaging the cross-piece I88, so that saidlever is moved angularly' about its pivotal position shown in Fig. 3 against the action of the I coil spring 2Ia when said cross-piece is moved upwardly.

Inorder to open the fuel valve Ifla independ ently of the operation of the change-over valve l2a, and hold said valve in this position, there is provided a bell crank lever III, pivoted at Hi to a frame bracket H6, and having one arm III thereof constituting the operating handle, and the other arm IIB serving to engage a collar I20, which is amxed to the upper end of the stem la, and against which the coil spring 2Ia acts. Extending transversely from the handle III is a lug I2I, adapted to be secured to a fixed frame arm I22 by means of a suitable locking pin I23. This valve holding mechanism is particularly useful to keep the fuel oil valve open during preheating and starting, and when testing the

control mechanism

39, 39a.

If desired, the two valves Ida and II may be operated by remote control by mechanical or other means, for example, from the engine platform or from the deck of the ship.

As many changes could be made in the above construction, and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A steam power plant mechanism comprising a main stop valve on the outlet side of a power plant steam boiler, the outlet side of said valve being connected to steam mains leading to the prime movers of the power plant, a control piston for said stop valve having boiler pressure acting on one side thereof, a change-over valve comprising a reciprocable valve member, a first pipe connection from asource of' boiler pressure to said changeover valve. a second pipe connection shutting off communication between said second and third pipe connections, and establishing communication between said first pipe connection and said second pipe connection, when said change-over valve is operated into another position to open said stop valve, a safety piston movable with said valve member, the steam pressure in said first pipe connection acting on one side of said safety piston, and a pipe connection from the other side of said safety piston to the steam mains on the outlet of the main stop valve, said safety piston being of such area, that when the pressure in said steam mains falls below a predetermined amount, the differential pressure acting on said safety piston is sumcient to move said valve member into position to close the main stop valve, independently of the position of said change-over valve.

2. A steam power plant mechanism comprising a main stop valve on the outlet side of a power plant steam boiler, the outlet side of said valve being connected to steam mains leading to the Y prime movers of the power plant, a control piston for said stop valve having boiler pressure acting on one side thereof, a change-over valve comprising a reciprocable valve member, a first pipe connection from a source of boiler pressure to said change-over valve, a second pipe connection between said change-over valve and the other side of said piston, and a third'pipe connection to said change-over valve from a source of steam pressure substantially lower than the boiler pressure, andmeans for establishing communication between said second and said third pipe connections through said change-over valve, and for shutting oil. communication between said first vpipe connection and the other pipe connections,