US3044492A - Valves - Google Patents

Description

July 17, 1962 c. M. PETERS ETAL 3,044,492

VALVES Original Filed July 26, 1955 I 2 Sheets-Sheet 1 Verna/7 5. Jca f/ (hf/ore M Pe/e/J INVENTORS July 17, 1962 c. M. PETERS ETAL 3,044,492

VALVES Original Filed July 26, 1955 2 Sheets-Sheet 2 M as 5 Verna/7 5. \Scaff C 0199/0 M. Fe fer:

INVENTOR) United States Patent O 3,644,492 VALVES Ciifiord M. Peters and Vernon B. Scott, Longview, Tex., assignors to US. industries, Inc., New York, N.Y. Original application July 25, 1955, Ser. No. 524,357, now Patent No. 2,890,138, dated July 23, 1957. Divided and this application Mar. 14, 1957, Ser. No. 646,018 5 Claims. (Ci. 137-62515) This invention relates to valves particularly useful in automatic tank switching systems but which can have other uses.

This application is a division of our copending application, Serial No. 524,357, filed July 26, 1955, now Patent No. 2,800,138 issued July 23, 1957.

In the petroleum production industry, as well as others, it is common to use a battery of tanks for temporary storage of crude oil or other products. For example, in the production of oil wells, it is common to provide a battery of tanks serving a multiplicity of wells for temporary storage of the oil production prior to its delivery to the pipeline. In order to gauge the tanks and determine how much oil is to be delivered to the pipeline, the production is usually flowed into a tank until it is filled whereupon the production is switched to a second tank. While the second tank is filling, the first one is gauged, its temperature taken and other measurements made whereupon it is emptied into the pipeline. In the usual installation, at least three and frequently six or more tanks are provided in the tank battery to provide ample storage and flexibility of operation.

Heretofore, it has been a common practice to equip the tank battery with manually operated valves to con trol flow into the various tanks. This arrangement has necessitated the pumper or gauger to be present when a tank is about to become filled in order that the production can be switched into an empty tank.

To eliminate the human element and manpower needed though preceding tanks are empty and otherwise ready to receive production. In other switching systems, there has not been provided an interlocking arrangement whereby flow into a succeeding tank in a series is positively prevented while-a preceding tank is being filled or whereby opening a tank'to production in itself positively closes all succeeding tanks to production. Further, the prior art systems have not provided any system where a tank, upon filling, is positively locked out of production until the pumper determines it is available to receive production.

An object of the invention is to provide a pilot valve particularly adapted for use in a tank switching system in which a plurality of such pilot valves are provided, one for each tank, the pilot valves being constructed to permit them to be interlocked in such a manner that only one tank at a time can he opened to receive or discharge fluid and upon becoming filled or emptied, the flow of fluid is switched to another available tank.

Another object of this invention is to provide a pilot valve particularly adapted to be employed to sequentially apply the pressure of a pneumatic medium to flow valves each con-trolling flow into or from a tank and upon a tank becoming filled or emptied, to switch such medium 3,044,492 Patented July 17, 1962 to the pilot valve of a succeeding tank, the pilot valve of a filled tank remaining in a position to prevent furtherflow into such tank not only until all such succeeding available tanks have been filled but also until the filled tank has been emptied and determined to be ready to' again receive fluid.

Another object is to provide a pilot valve constructed to switch a pneumatic control medium from a flow valve controlled thereby to a succeeding pressure actuated mechanism responsive to an impulse received by the pilot valve, the pilot valve remaining locked in its switched position until moved to a position to permit application of pneumatic medium to its flow valve responsive to another impulse received by the pilot valve.

Another object of the invention is to provide a control valve mechanism in which a pilot valve is used as a part of the mechanism in a manner so as not to bleed any substantial amounts of the pneumatic medium to the atmosphere.

Another object is to provide a pilot valve for use in a control system in which the inlet flow valve to a tank is positively locked in closed position while the outlet flow valve is open.

Another object of the invention is to provide a pilot FIG. 2 illustrates an alternative detent or locking means useful with a valve of the type shown in FIG. 1;

FIG. 3 is a partial view showing a modification of the valve of FIG. 1 particularly adapting the valve for use with the last one in a series of tanks; and

FIGS. 4 and 5 are somewhat schematic illustrations showing the pilot valve of this invention installed in a tank switching system.

Like characters of reference are used throughout the several views to designate like parts.

In general, this invention provides a pilot valve adapted to be used on each of the inlet flow valves of the individual tanks of a tank battery and which is operable to apply an energizing medium to the first flow valve so medium to the first flow valve so that it can close and I then transmits the energizing medium to a second pilot valve to cause the second tanks flow valve to be opened. This switching and transmission continues until all of the available tanks in the battery have been filled. When the last available tank in the series has been so filled, the energizing medium is transmitted to the pilot valves of the preceding tanks to urge them to a position to again apply the energizing medium to the flow valve of the first tank in the series and if it is not available to the flow valve of the next available tank. The pilot valves'block flow to a succeeding flow valve until all preceding available tanks have been filled. Thus the pilot valves are constructed to provide an interlock whereby all available tanks must be filled serially and two or more of them cannot be placed on the line at the same time. The pilot valves are also constructed so that as each tank is filled, it is automatically locked out of the system until the pumper or gauger has finished gauging and determines the tank is ready to go back on the line.

Referring to FIG. 1, a pilot valve is shown which is suitable for use as pilot valves 51 and S2 of FIGS. 4 and 5 or for other uses, 7 This valve comprises a body 57 having an inlet port 58 to which a conduit 43 can be connected. A pair of outlet ports 59 and 69 are also provided for respective connection with conduits 54 and 49. These various ports communicate with a bore 61 through which flow is controlled by a valve member such as shiftable plunger 62. The plunger has spaced seals, such as O-rings 63 and 64, with an intermediate reduced diameter portion 65 arranged so that when the plunger is in the position shown in FIG. 1, communication bet een the ports 58 andv 59 is efiected' while port 60 is blanked off from port 58. This position will, for convenience, be hereafter referred to as the fill position. Upon shifting plunger 62 to the right in FIG. 1, seals 63and 64 are moved so that port 58 is placed in communication with port 60 and out of communication with port 59. The latter'in turn is in communication via reduced diameter portion 66 with a vent 67 in the valve body. This position will hereafter be referred to as the switched position. With this construction pressure fiuid from conduit48 can be applied through conduit 54, with the valve plunger in fill position, to flow valve 45 to open it (-FIG. 4). Upon shifting of plunger 62 to switched position, the pressure fluid is diverted or switched to the snag 1.92

To facilitate describing the operation of the pilot valve, a schematic tank switching system is illustrated in FIGS. 4 and 5. In FIG. 4, the system is positioned for fluid to flow into a tank from valve 45 through conduit 42 while two other tanks are empty and ready to receive fluid in turn from valves 46 and 47, respectively. Pressure fluid, say at 25 p.s.i., flows from source S through conduit 4-8 and thence through pilot valve 51 to act against the diaphragm of flow valve 4-5 to hold it in open position. As

next succeeding pilotvalve'while flow valve is bled oil through vent 67 thereby permitting it to close.

Means are provided for shifting plunger 62 between its fill and switched positions responsive to signals received from exteriorly ofthe valve. Thus, there can be provided two pressure responsive means in the form of pistons 6S and 69 respectively slidable in bores 70 and 71 of the valve body and having a sliding seal therewith as by O-rings 72 and 73. Piston 68 is arranged so it can abut plunger 62 to move it to switched position and then move relative to the plunger to a retracted position wit out moving the plunger. The pistons movement in one direction is eiiected by the application of a pressure medium through an inlet fitting 7 4 and in the other direction by resilient means such as spring75 so that when sufiticient pressure is applied through fitting 74 to overcome spring 75, the piston will move to the right to shift the valve plunger to switched position.

Detent means are provided which are operable and effective to maintain the piston in switched position where it prevents shifting of the valve plunger to fill position until the detent means is released. As shown in FIG. 1, the detent means comprises a manually operable plunger 76 which is spring pressed by spring 77 to cause an end 78 to ride against the piston andv eventually drop into groove 79. Hence, once piston 68 hasshifted the valve plunger, it is prevented from returning to its retracted position by the detent means and this retains the valve plunger in itsswitched position. The purpose of this ar rangement is to enable a tank to be locked out of service until the pumper has determined it should be placed back in service which he can do merely by lifting up on the detent so spring 75 can move the piston.

Piston 69 is likewise shown to be separate but abutable with the valve plunger upon application of fluid pressure thereto from one of ports 80 01181. It will be noted that the cross-sectional area of'piston 69 is made sufliciently smaller than that of piston 68 that pressure acting through ports 89 or 81 cannot develop a force sufsoon as the tank controlled by valve 45 is filled sufficiently, liquid level control 85 (controls 65, $6 and 87 being operated by the liquid levels in the tanks) applies pressure from source S through conduit 32 against piston 68 of the pilot valve to cause the pistonand valve plunger to move to switched position. This movement bleeds oil? flow valve 45 and permits it to close. At the same time, piston 63 is locked by detent 76 in its shifted position which, of course, prevents opening valve 45 until the detent is released.

Pressure fluid from source S hasby such movement been switched to flow through pilot valve 51, conduit 49, pilot valve 52 and conduit 55 to flow valve 46 to open it and admit flow through conduit 43 to a second tank. As soon as the tank controlled by valve 46 is filled, liquid level control '86 will act through conduit 33 to admit fluid from source S and conduit '88 to piston 68 of valve 52 and cause pilot valve 52 to be shifted to close valve 4-6 and apply pressure fluid via conduit 50 to pilot valve 53 and conduit 56 to valve 47 to open it and admit flow through conduit 44 to a third tank. Then upon filling of the tank controlled by valve 47, the same manipulation of pilot valve 53 occurs through liquid level control 57 and conduits 84 and 88 whereupon pressure from source S, instead of being applied to the next pilot valve, is brought back through conduit 89' to be applied against each of pistons 69 in pilot valves 51 and 52. If it is assumed, for example, that the tank controlled by valve 46 has beenemptied before the last tank completes its filling, the pumper can raise the detent on pilot valve 52 so that its piston 68 moves to retracted position a shown in FIG. 5. This movement does not move the valve plunger but it remains in the position shown in FIG. 5. Then upon filling of the last tank, pressure applied through conduit 89 shifts the plunger of pilot valve 52 cutting off the supply of pressure to pilot valve 53 and diverting it to flow valve 46 which opens. In FIG. 5, it is assumed that the tank controlled by valve 45 has not been emptied or for some reason is not to be refilled and therefore the detent on its pilot valve has not been released. 'As a result, the application of pressure to this pilot through conduit 89 does not cause shifting of its plunger so that pressure fluid. from source S continues to be applied through the pilot valve to the inlet of pilot 52. If this tank had been ready for filling and the detent on its pilot had been released, the pressure in conduit 89' would have been effective to shift the plungers of both pilot valves 51 and 52.

, This would cause pressure from source S to be applied first to flow valve 45 and then upon its tanks filling, to

ficient to move the plunger to fill position until pressure V on piston 68 has been released.

In FIG. 3 is shown a partial view of a valve useful as the last pilot valve in the series on tank battery. In FIG. 4, this would correspond to pilot valve 53. The valve of FIG. 3 can beexactly like that of 51G. 1 except that piston 69 is replaced by a resilient means such as spring 80a and a s'pring'guideand retainer 810. This arrangement constantly urges the valve plunger to fill position and no pressure fluid is required for such shifting.

In each of the valves of FIGS. 1 and 3, a sight index and manual shifter can be provided in the form of 'a pin 62a connected to the valve plunger.

flow valve 46. Pressure fluid may be released from conduit 89 tlirough valve 114 and conduit 115 as and for the purpose described in the aforesaid application Serial No. 524,357, now Patent No. 2,800,138, or will bleed ofi through choke 139. V

It may sometimes happen that one of the intermediate tanks in the series has been emptied and made available after the last'tank'has been filled and while a preceding tank is being filled. In such event, the release of the detent on the pilot valve of such intermediate tank would not cause shifting of the plunger so that the tank could be filled in its proper turn after the preceding tank had been filled or skipped. For example, should the tank controlled by valve 47 become filled while pilot valve 52 is movement of pilot valve 53 to switched position, thereby shutting ofi gas flow of pilot valve 53 and hence to line 89. Then, upon filling of the tank controlled by valve 45, pilot valve 51 will be moved to switched position. Even if prior to this, detent 76 of pilot valve 52 has been released, pilot valve 52 will remain in switched position, causing the tank controlled by valve 45 to be skipped. To avoid this, the pilot valves are constructed so that a conduit 90 can be provided to communicate between port 59 of one pilot valve to port 81 of the next succeeding pilot valve. Then pressure acts through conduit 90 during the filling of the tank controlled by valve 45 to immediately shift the valve plunger of pilot valve 52 upon release of its detent. Thus, the detent of a succeeding pilot valve can be released any time during the filling of a preceding tank and yet such pilot valve will be moved to fill position so that the tank it serves will not be skipped. To prevent pressure from being applied to conduit 89, a check valve 91 can be supplied in each branch of this conduit leading to the intermediate pilot valves. Of course, conduit 90 could be eliminated with the result that an intermediate tank which has been emptied and made.

means, the latter being released upon removal of such signal. With this arrangement, the detent means of FIG. 1 is replaced by that of FIG. 2. The latter includes a cylinder 92 housing a piston 93, the latter being movable in one direction by fluid pressure applied through fitting 94 and urged in another direction by spring 95. The piston carries a detent part 96 which upon application of pressure to the piston, is engageable with groove 79. In use, fitting 94 can be connected to a bleed type pilot which is actuated by, for example, a flow valve so that pressure signals are alternately applied and removed from the detent as the bleed type pilot is actuated. With this arrangement, piston 68 of the pilot valve will be retained in its switched position by pressure applied to piston 68 until such pressure is relieved. Thereupon, the bleed type pilot can apply pressure to piston 93 to detain piston 68 of the pilot valve until the bleed type pilot is actuated to bleed 015 such pressure.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings it is to be interpreted as illustrative and not in a limiting sense.

1. A selector pilot valve comprising a valve body having first, second and third ports, passage means connectingsaid ports, a valve member movable in said passage means between a first position to restrict flow to be between said first and second ports and a second position to restrict flow to be between said first and third ports, first pressure responsive means for urging the valve member toward its first position, second pressure responsive means movable in one direction to move the valve member to its second position and then being free to move in an opposite direction without causing movement of the The invention having been described, what is claimed valve member to its first position, detent means operable and effective to engage said second pressure responsive means upon its movement of the valve member to its second position and there to hold the second pressure responsive means until released, and resilient means urging said second pressure responsive means in said opposite direction.

2. The valve of claim 1 wherein said valve member comprises a valve plunger and wherein said second 'responsive means includes a piston abutting said plunger so that movement of the piston in said one direction causes the plunger to move to said second position and upon release of said detent means, said piston can move out of abutment with the plunger without moving the same to its first position.

3. A pilot valve comprising a body having a flow inlet and first and second outlets, a valve member movable in said body between first and second positions in which it respectively confines flow from the inlet to be to said first and second outlets, a vent in the body positioned to be in fluid communication with the first outlet when the valve member is in its second position, and first and. second pressure responsive means carried by the body and operable to respectively urge the valve member toward its second and first positions responsive to pressure signals applied to the pressure responsive means, the first pressure responsive means being of greater ettective area than the second so that when pressure signals of substantially equal magnitude are applied to both pressure responsive means, the valve member will be positioned in its second position, said first pressure responsive means also being movable independently of the valve member when the latter is in its second position.

4. The valve of claim 3 in combination with detent means carried by the body and engageable with one of said valve member and first pressure responsive means when the valve member is in its second position but releasable to permit movement of the valve member to its first position upon application of a pressure signal to the second pressure responsive means and upon reducing any pressure signal being applied to the first pressure References Qited the file of this patent UNITED STATES PATENTS 960,986 Moore June 7, 1910 1,091,108 Allen Mar. 24, 1914 1,239,566 Conrader Sept. 11, 1917 1,392,697 Neesham Oct. 4, 1921 1,743,055 Walker Jan. 7, 1930 1,920,003 Chenault July 25, 1933 2,276,979 Jacobi Mar. 17, 1942 2,304,323 Wiegers Dec. 8, 1942 2,322,517 Hose June 22, 1943 2,326,487 Overbeke Aug. 10, 1943 2,341,411 Ojalvo Feb. 8, 1944 2,617,257 Douglas Nov. 11, 1952 2,645,450 Chessman July 14, 1953 2,751,182 Snyder June 19, 1956 2,781,996 Smallpiece Feb. 19, 1957 2,880,755 Brown Apr. 7, 1959 FOREIGN PATENTS 496,454 Germany of 1930 455.718 Italy of 1950

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