US 3872899 A
A vapor recovery fluid loading arm especially for transferring gasoline or other volatile fluids from a reservoir thereof to a tank truck, railway tank car, or other receptacle, and recovering the vapors evolved therefrom. The loading arm has a dripless discharge spout that prevents residual fluid from draining out of the spout after the flow control valve in the arm is closed, thereby preventing spillage and corresponding pollution of the atmosphere. Four different embodiments of dripless discharge spouts are described, each of which has a closure element that shuts off the flow of fluid through it in response to a predetermined condition or signal.
Claims available in
Description (OCR text may contain errors)
act  nite Knight 1 Mar. 25, 1975 [541 VAPOR RECOVERY FLUID LOADING ARM WITH DRIPLESS DISCHARGE SlPOUT  U.S. Cl ..141/59, 141/198, 141/279, 1 141/293, 141/388  int. Cl .8651) 31/00 Field of Search 141/279, 284, 387, 388,
 References Cited 9 UNITED STATES PATENTS 2,479,454 8/1949 Annin 251/613 2,726,800 12/1955 Burdin 141/294 2,809,677 10/1957 Hamner 141/59 2,963,205 12/1960 Beall Jr 141/292 Gowens 141/293 Madden et a1 141/388 Primary Examiner-Richard E. Aegerter Assistant Eramirzer-John W. Shepperd Attorney, Agent, or Firm-W. W. Ritt, Jr.; C. E. Tripp  ABSTRACT A vapor recovery fluid loading arm especially for transferring gasoline or other volatile fluids from a reservoir thereof to a tank truck, railway tank car, or other receptacle, and recovering the vapors evolved therefrom. The loading arm has a dripless discharge spout that prevents residual fluid from draining out of the spout after the flow control valve in the arm is closed, thereby preventing spillage and corresponding pollution of the atmosphere. Four different embodiments of dripless discharge spouts are described, each of which has a closure element that shuts off the flow of fluid through it in response to a predetermined condition or signal. 1
6 Claims, 10 Drawing Figures PATENTEUMARZSIHYE SHEET 1 0F 5 Q. d vm $0 9 wm F 9. N t
PATENTED 55175 sum 3 or 5 uw milwu PMENTEDHARZSISYS SHEEF k (If 5 PATENTED MAR 2 5 975 m m-inhil 1 I VAPOR RECOVERY FLUID LOADING ARM WITH DRIPLESS DISCHARGE SPOUT BACKGROUND OF THE INVENTION The field of art to which the present invention pertains includes apparatus for transferring fluid between vessels, and more particularly to vapor recovery types of fluid loading arms. The relevant areas of the U.S. patent classification system include class 137, subclasses 615 and 616, and class 141, subclasses 206, 290 and 291.
The transfer of volatile fluids such as gasoline between a storage reservoir and a tank truck or railway tank car is invariably accompanied by the generation of large volumes of vapor. To prevent this vapor from escaping and polluting the atmosphere, vapor recovery loading arms have been devised to capture the vapor while the liquid is being delivered into the transport vessel, and then return the vapors back to the storage reservoir or to another suitable container. These vapor recovery arms comprise a dual system of articulated pipes terminating in a single delivery head that is inserted into the hatch of the tank truck or railway tank car, one of the pipe systems for conducting fluid to the tank and the other system for returning the vapors to the reservoir. Apparatus of this type is described in detail in U.S. Pat. Nos. 3,099,297 and 3,176,730.
Although these devices perform satisfactorily, recent concern for the purity of the environment has resulted in laws governing the amount of vapors and other pollutants that can be released to the atmosphere. Not only do the vapors that are lost pollute the air, but any volatile liquid that drains or spills from the loading arm also is a potential atmospheric pollutant because of eventual volatilization of its components. Therefore, when loading gasoline or other volatile 'liquid into a tank truck, railway tank car, etc., it is now very important to prevent any liquid from dripping from the delivery head as it is withdrawn from the tank and returned to its stowed position.
The delivery heads of the vapor recovery loading arms described in the aforementioned U.S. patents provide an excellent means for conducting the liquid from the arm into the tank truck or railway tank car, and for conducting the evolved vapors into the vapor return line of the arm. However, these delivery heads have no provision for preventing residual liquid that is always present therein from dripping off the head as it is raised out of the tank and returned to its stowed position. In an effort to avoid this dripping problem, it has been suggested to leave the delivery head in the hatch for a brief draining period before it is removed. Although this delay is sometimes effective, it is of no help when the tank is overfilled, or when the delivery head is otherwise immersed in the liquid in the tank.
SUMMARY OF THE INVENTION The present invention overcomes the foregoing problems by providing a dripless discharge spout to close off the fluid outlet of the delivery head on a vapor recovery fluid loading arm, thus preventing fluid from dripping out of the head and subsequently volatilizing into the atmosphere. According to the present invention the fluid conduit portion of the delivery head empties into a discharge spout with a valve closure element that opens in response to a predetermined signal or condition to allow fluid to flow, and then closes fluid tight in response to another predetermined condition or signal before the delivery head is raised out of the tank. This valve element also opens and closes the vapor return passageway through the head, either directly or in conjunction with other of the elements in the head, thereby also preventing escape of vapors to the atmosphere. The invention includes loading arms having spouts with an external valve closure element in the form of an annular sleeve that surrounds the spout and that is caused to slide axially on the spout between closed and open positions as the spout is inserted into and withdrawn from a tank hatch, spouts with internal poppet type valves that open and close in response to sliding movement of an annular dome seat surrounding the spout, spouts with internal poppettype valves that open and close in response to air pressure that is applied to a pneumatic cylinder, and spouts with fluid control valves coupled to vapor check valves to control flow of both fluid and vapor.
Accordingly, one object of the present invention is to provide an improved type of vapor recovery fluid loading arm.
Another object of the present invention is to provide a new type of fluid discharge spout for a vapor recovery fluid loading arm that prevents escape of fluid and vapor to the atmosphere when the spout is not positioned in a fluid receptacle.
Yet another object of the present invention is to provide a means for automatically closing the exit port in a fluid discharge spout of a vapor recovery fluid loading arm when the spout is withdrawn from the tank into which fluid has been delivered.
A still further object of the present invention is to provide a dripless discharge spout for use in conjunction with the delivery head of a vapor recovery fluid loading arm.
Another object of the present invention is to provide apparatus for trapping the residual liquid and vapor in a vapor recovery fluid loading arm and preventing them from escaping to the atmosphere when the arm is not in its fluid delivering position in a receptacle.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a vapor recovery fluid loading arm with a dripless discharge spout according to the present invention.
FIG. 2 is a plan view taken along the line 22 of FIG. 1.
FIG. 3 is a sectional view, on an enlarged scale, taken along the line 3-3 of FIG. 1, showing the discharge spout in its closed condition and positioned in a tank hatch.
FIG. 4 is a view like FIG-3, but showing the discharge spout in its full open condition.
FIG. 5 is a vertical section view, similar to FIG. 3, of a second embodiment of dripless discharge spout according to the present invention.
FIG. 6 is a view like FIG. 5, but showing the discharge spout in its full open condition.
FIG. 7 is a vertical section view, like FIGS. 3' and 5, of a third embodiment of dripless discharge spout according to the present invention.
FIG. 8 is a view like FIG. 7, but showing the discharge spout in its full open condition.
FIG. 9 is a vertical section view, like FIGS. 3, 5 and 7, of a fourth embodiment of dripless discharge spout according to the present invention.
3 FIG. is a view like FIG. 9, but showing the discharge spout in its full open condition.
DESCRIPTION OF THE PREFERRED EMBODIMENT In reference first to FIGS. 1 and 2 of the drawings, the numeral 12 designates a vapor recovery fluid loading arm embodying the principles of the present invention. This arm 12 compriese an inner boom section 14, an outer boom section 16, and a delivery head assembly 18 to which is connected a dripless discharge spout 20. Much of the arm 12 is substantially the same as the arms of the aforementioned Knight US. Pat. Nos. 3,099,297 and 3,176,730, and therefore these patents are hereby expressly incorporated by reference into this description.
The inner boom section 14 of the arm 12 includes a pair of parallel rigid pipes or conduits 22, 24 positioned one above the other in the same vertical plane. The inner ends of the conduits 22, 24 are connected to pipe swivel joints 26, 28 for pivotal movement about a common vertical axis A. In a normal installation of this arm on a gasoline tank truck loading rack, the lower swivel joint 26 is connected to a fluid riser pipe 32 from which gasoline is delivered from a storage reservoir (not shown) to the conduit 22. In similar manner, the upper swivel joint 28 is connected to a vapor riser pipe 34 that conducts vapors from the conduit 24 to a suitable recovery system, to the storage reservoir, or to some other desired location. Riser pipes 32, 34 usually are mounted by means of suitable brackets 36 to a rigid support member 38 at the loading rack.
The outer boom section 16 of the arm 12 comprises a pair of parallel rigid pipes or conduits 40, 42 that are oriented in a side-by-side relationship in a common, generally horizontal plane. Between, and interconnecting, the inner and outer boom sections 14, 16 is a fluid cross assembly 44. The outer ends of the inner boom conduits 22, 24 are connected to the cross assembly 44 by two axially aligned swivel joints 46, 48 that are oriented on a common vertical axis B. The inner ends of the outer boom conduits 40, 42 are connected to the cross assembly 44 by a pair of swivel joints 50, 52 that are co-axial on the generally horizontal axis C. Cross member 44 is constructed to provide separate communication between the fluid delivery conduits 22, 40, and between the vapor return conduits 24, 42.
Accordingly, it should be understood that the outer boom section 16 can be pivoted both horizontally about the axis B and vertically about the axis C with respect to the inner boom section 14, and that this capability along with that of the inner boom section 14 to pivot about the vertical axis A facilitates positioning the delivery head 18 at any location within the loading arm s reach.
The delivery head 18 is connected to the outer end of the conduits 40, 42 by a pair of swivel joints 54, 56 that are co-axial on a horizontal axis D. Thus, the pivot axes A, B, C and D enable the delivery head 18 to be placed in any location within the operating area or envelope of the loading arm 12.
Horizontal movement of the loading arm 12 about the vertical axes A and B is accomplished manually, and vertical movement of the outer boom section 16 relative to the inner boom section 14 is accomplished by means of a pneumatic cylinder 60. As seen in FIGS. 1 and 2, cylinder 60 is pivotally mounted on a pair of brackets 62, 64 that are fixed to the conduits 40,42, respectively. The cylinders piston rod 66 is pivotally connected at 68 to a bracket 70 that is fixed to the cross assembly 44. Thus, as the cylinder 60 is actuated to extend the piston rod 66 the outer boom section 16 is elevated about the axis C, and as the piston rod 66 is withdrawn into the cylinder 60 the outer boom section 16 pivots downwardly about the axis C.
The cylinder 60 is powered by high pressure air that is conducted from a source thereof by an air line 72 fastened for support to the inner boom sections vapor return conduit 24, and then by a rigid air line 74 to multiposition, manually operated air control valve 76 pivotally mounted on an upstanding bracket 77 that is rigidly secured to the delivery head assembly 18. The air lines 72, 74 are interconnected by a flexible air line 78, and the inner end of the air line 74 is pivotally connected at 79 to the fluid cross assembly 44. Thus the air line 74 and the outer boom section 16 comprise opposite sides of a pantograph system that maintains the delivery head assembly 18 in a vertical or other preselected attitude as the outer boom section 16 is pivoted upwardly and downwardly about the axis C.
The air control valve 76 is connected to opposite ends of the cylinder 60 by air lines 80, 82, thereby providing a means to actuate the cylinder for raising or lowering the outer boom section 16 as desired.
A fluid delivery control valve 84 is incorporated in the outer boom sections fluid delivery conduit 40 to control the flow of fluid through the loading arm 12 to the delivery head assembly 18. This valve 84 preferably is of the type described in Bloomquist US. Pat. No. 3,206,158, the subject matter of which is expressly incorporated herein. The control valve 84 is connected by an air line 86 to a contact valve assembly 88 that is mounted on the side of the delivery head assembly 18, and an air line 90 connects the contact valve assembly 88 to the manually operated air control valve 76. -As fully described in the aforementioned Bloomquist patent, the fluid delivery valve 84 opens when air under pressure is admitted to it through line 86, and when that air pressure is cut off the valve 84 automatically closes. The contact valve assembly 88 which can be of the type described in the aforementioned Knight US. Pat. No. 3,099,297, functions to prevent inadvertent opening of the fluid delivery control valve 84 unless the delivery head assembly 18 is properly positioned in the hatch of a tank truck, railway tank car, etc., thereby avoiding spills of fluid. Various other systems for controlling the operations of the fluid delivery valve 84 and the cylinder 60, such as those described in the aforementioned Knight US. Pat. No. 3,176,730 and in G. W. Bloomquists pending US. patent application Ser. No. 282,809, filed Aug. 22, 1972, now US. Pat. No. 3,825,045, issued July 23, 1974, can be utilized with this loading arm 12 depending upon the desires of the user.
FIGS. 3 and 4 illustrate on an enlarged scale the details of the dripless discharge spout 20 and the lower portion of the fluid delivery head assembly 18 to which it is attached. As seen in these figures, the delivery head assembly 18 comprises a tubular housing 92 that terminates in a radial annular flange 94 that provides a means for connecting to it the dripless discharge spout 20. An inner wall 96 separates the housing 92 into two passageways 98, 100. The passageway 98 is in communication with the outer boom sectons fluid delivery conduit 40 through the valve 84, and thus functions to conduct fluid through the head assembly into the dripless discharge spout 20. The passageway 100 is in communication with the outer boom sections vapor return conduit 42, and thus functions to conduct vapors coming from the tank T through the discharge spout into the vapor return conduit 42.
The dripless discharge spout 20 comprises a body 102 with a tubular upper portion 103 having a radial annular flange 104 for connecting the spout 20 to the flange 94 of the delivery head assembly 18. An inner suitably curved wall 106 separates the body 102 into a fluid delivery'passageway 108 that forms a continuation of the delivery heads passageway 98, and a vapor return passageway 110 that communicates with the delivery heads vapor return passageway 100 through a port 112. A vapor check valve 114, comprising a piston-type closure member 116 enclosed in a valve housing 118 and biased to a closed position (FIG. 3) by an adjustable spring 120, is mounted on the spouts upper portion 103 over the port 112. The check valve housing 118 has a plurality of circumferentially spaced ports 122, so that when the valve member 116 is open (FIG. 4) the vapors in the vapor return passageway 110 pass through the port 112 and the ports 122 into the head assemblys vapor return passageway 100.
The inner wall 106 of the dripless discharge spouts body 102 extends downwardly to a circular lower end portion 124 having a conical-shaped outer surface 126. The annular periphery of the end element 124 is grooved at 128 to retain an annular O-ring or other suitable seal element 130. The end portion 124 is spaced from the lower annular end 132 of the spouts upper portion 103 an amount adequate to provide smooth discharge of fluid from the passageway 108 into the tank T, and to provide adequate inlet area for vapors from the tank T into the passageway 110.
The dripless discharge spout 20 further includes an annular dome seat 134 concentrically and slidably disposed about the upper portion 103 of the spouts body 102. Surrounding the dome seat 134 is an outer annular tank seal 136 of rubber or other suitable resilient material that establishes a vapor tight seal with the rim R-of the tanks hatch H. The lower portion 138 of the dome seat 134 extends downwardly and inwardly from the seats cylindrical upper portion 140, and then terminates in a lower end 142 with a conical surface 144. This conical surface 144, which as a taper of about 5, wedges against the O-ring 130 when the dome seat is in its lower or closed position (FIG. 3). This establishes a fluid-tight seal with the spouts lower end portion 124 and closes off the passageways 108, 110, thereby preventing escape of fluid or vapors from within the spout to the atmosphere. The dome seat 134 normally is in this lower, closed position when the spout is outside of the hatch H, and also when it is in the hatch as shown in FIG. 3, but not yet fully seated as shown in FIG. 4.
When the spout 20 is fully seated (FIG. 4), its body 102 has moved downwardlywithin the dome seat 134 until the radial flange 104 has come to rest on the upper surface 146 of the seats upper portion 140. In this condition an annular. opening, separated by the wall 106 into a fluid outlet port 148, and a vapor inlet port 150, exists between the seats lower end 142 and the bodys lower end portion 124. Also, in this open" position, the seat 134 is sealed to the body 102 by an O-ring or other suitable annular seal 152, so that no fluid or vapor can escape to the atomsphere. As the level of the fluid in the tank T approaches full, the fluid will enter the vapor inlet 150 and cause the float 154 to rise, actuating the contact valve 88 to cause the fluid delivery valve 84 to close, all as is described in detail in the aforementioned Knight US. Pat. No. 3,099,297.
THE EMBODIMENT OF FIGS. 5 AND 6 The dripless discharge spout 200 illustrated in FIGS. 5 and 6 constitutes another embodiment of the present invention. This spout 200 comprises a tubular body 202 having an upper portion 204 with an annular radial flange 206 for connecting it to the flange 94 of the delivery head assembly 18, and a lower portion 208 that gradually curves inwardly to terminate in an inward sloping end section 210. A curved inner wall 212 divides the body 202 into a fluid passageway 214 that communicates with the fluid passageway 98 of the head assembly 18, and a vapor return passageway 216 that communicates through the check valve 114 with the head assemblys vapor return passageway 100.
A poppet-type valve 218, comprising a valve disc 220 on a valve stem 222, is slidably supported in the spouts body 202 by a guide element 224 through which the stem extends, and a transverse rod 226 that extends through diametrically opposed vertical slots 228 (only one shown) in the side of the spouts body 202 and to which the stem 222 is attached by means of a junction block 230. The outer ends of the rod 226 are secured in an annular dome seat 232 that is slidably disposed about the spouts body 202, and that has an annular tank seal 234 of rubber or other suitable resilient material surrounding its outer periphery.
The spout body 202 has a vapor inlet window 236 in its side that is located to be closed [by the dome seat 232 when the seat is in its lower position, shown in FIG. 5, and to be open when the dome seat is in its upper position, i.e., when the spout 200 is fully seated in a hatch H of a tank T, as seen in FIG. 6.
An annular resilient seal 238, residing in a groove 240 in the outer surface of the spout body 202, effects a fluid-tight seal between the body 202, and the dome seat 232 when the seat is in its lower position (FIG. 5), and also prevents the seat from sliding off the body. Another annular seal 242, residing in a groove 244 in the inner surface of the dome seat, seals the seat fluidtightly at its upper end to the spout body 202.
When the dome seat 232 is in its normal lower position (FIG. 5) the poppet valve 2.18 is closed, a fluidtight seal between its disc 220 and the spouts lower end 210 being provided by an annular resilient seal 246 that is secured to the disc 220. A coil spring 248 surrounding the valve stem 222 biases the valve towards its closed position, thereby aiding the dome seat in holding the valve disc 220 tightly against the spouts lower end 210.
As the spout 200 is lowered into its fully seated position, the spout body 202 moves downwardly away from the valve disc 220, opening the lower end of the spout to allow fluid flow into the tank T. At the same time, the vapor inlet window 236 is opened, permitting vapor to pass from the tank through it and on upwardly through the check valve 114 into the vapor return conduits of the loading arm. Of course, when the fluidlevel in the tank reaches the float 250, the float rises and actuates the contact valve 88, causing the fluid delivery valve 84 to close, all in the previously described manner.
THE EMBODIMENT OF FIGS. 7 AND 8 FIGS. 7 and 8 illustrate one embodiment of the present invention wherein a pneumatically powered poppet-type valve is employed to open and close the fluid outlet in the dripless discharge spout. In the embodiment the discharge spout 300 comprises a tubular body 302 having an annular radial flange 304 at its upper end for connecting it to the head assemblys flange 94, and a central fluid outlet 306 at its lower end 308. The body 302 has an inner wall 310 that divides it into a fluid passageway 312 and a vapor passageway 314. The body 302 has a vapor window 316 for inletting vapor from the tank T to the vapor passageway 314 when the dome seat 318 in its upper position (FIG. 8).
The inner wall 310 has a tranverse lower portion 320 that provides a mounting for a double-acting pneumatic cylinder 322. The cylinders piston rod 324 extends through the lower wall portion 320 and is secured at its lower end to a poppet-valve disc 326. Thus, as the cylinder is actuated by means of compressed air though air lines 328 or 330 the valve disc is caused to move down or up, respectively, to close or open the spouts fluid outlet 306. The valve disc has an annular groove 332 in its periphery to retain an O-ring of rubber, or other suitable seal, to provide a fluid-tight closure of the fluid outlet 306 and prevent the escape of droplets, etc., of volatile product being transferred through the arm 12.
The cylinder 322 can be connected into a suitable air line circuit so that it operates in several manners, including one in which it is responsive to a contact switch diagrammatically illustrated at 336. This switch causes compressed air to be inletted to the cylinder 322 through the air line 330 when the dome seat is in its upper position (FIG. 8) wherein it has pushed the switch shaft 338 upwardly. When the spout 300 is raised, the dome seat falls away from the switch, letting the shaft 338 drop and causing the compressed air to course instead through air line 328, thereby closing the valve disc 326.
Because of the possibility of the liquid level rising higher in the tank than the level of the spouts fluid outlet 306, thereby creating a vacuum in the fluid passageways when the spout is being lifted out of the hatch, a port with a check-type relief valve can be provided in the lower area of the vertical portion of the inner wall 310 if desired. Also, a port or ports with suitable check valves can be provided in the upper area of this vertical wall 310 to help equalize the fluid pressure in the head assembly when the fluid passageways are full and the poppet valve is closed.
In this embodiment, as well as that of FIGS. 3 and 4, and of FIGS. and 6, an upper annular seal 340 in a groove 342 in the inner surface of the dome seat 318 cooperates with a lower annular seal 344 in a groove 346 in the outer surface of the spouts body 302 to effectively seal the window fluid-tight when the dome seat is in its lower position shown in FIG. 7. These upper seals also effectively wipe any fluid from the outer surface of the spout body as the dome seat drops into this lower position.
THE EMBODIMENT OF FIGS. 9 AND 10 The embodiment of the invention illustrated in FIGS.
9 and 10 is practically identical to that of FIGS. 7 and 8, except for a different check valve in the vapor return passageway. Hence, where the elements are identical, they have been designated with the same numbers as in FIGS. 7 and 8.
In the FIG. 9 and 10 embodiment, a double-acting pneumatic cylinder 400 is employed to open and close a check valve 402, as well as to open and close the poppet valve 326. The check valve 402 comprises a valve piston 404 that is slidably mounted in a housing 406 secured to the upper end of the spouts body 302 over the vapor outlet 408, and biased towards its closed position (FIG. 9) by a spring 410. The piston 404 is raised into its open position (FIG. 10) by the piston rod 412, to which it is connected, when compressed air is inletted to the cylinder 400 through air line 330 to open the valve 326. The piston 404 is drawn downwardly into its closed position when compressed air is admitted through air line 328 into the cylinder 400. Hence, in this embodiment the check valve 402 is assured of being open when the spouts fluid outlet valve 326 is open, and closed when the valve 326 is closed.
Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention.
What is claimed is:
1. In a vapor recovery fluid loading arm including a fluid delivery conduit extending between fluid supply means and fluid dispensing means, and a vapor return conduit extending between said fluid dispensing means and a vapor receiving means, the improvement comprising a fluid outlet-vapor inlet assembly intermediate the fluid dispensing means and the atmosphere, said assembly including a. a generally tubular body having inner and outer ends, said inner end connected to said fluid dispensing means, said body separated into a fluid passageway and a vapor passageway by a generally longitudinal wall having a transverse web portion forming a mounting for a valve operating means,
b. a valve seat formed in the outer end of the tubular body,
c. a valve closure element for cooperating with the valve seat to form a barrier preventing fluid from passing to the atmosphere from the fluid passageway,
d. a valve operating means mounted on the web portion and connected to the valve closure element, and
e. valve control means connected to the valve operating means for controlling actuation of said operat ing means from a remote location.
2. A vapor recovery-fluid loading arm according to claim 1 including vapor valve means in the vapor passageway for preventing reverse flow of vapor from the vapor return conduit into said vapor passageway, said vapor valve means operably connected to the valve control means for operation with the valve closure element.
3. A vapor recovery-fluid loading arm according to claim 1 including float means in the vapor passageway of the tubular body, said float means operably connected to a fluid flow control valve for closing said valve to prevent fluid flow through the fluid conduit.
6. An apparatus according to claim 5 wherein the actuating means for the valve control means comprises a contact valve associated with and movable with respect to the fluid dispensing means, said contact valve disposed for movement in response to placing the fluid outlet-vapor inlet assembly into fluid delivery position in a receptacle.