US2169411A - Vapor saving and relief system - Google Patents

Description

Aug. 15, 1939. P. B. DRANE VAPOR' SAVING AND RELIEF SYSTEM F'iled Jan. 15, 1938 2 Sheets-Sheet l Aug. 15,. 1939. P1. B; DRANE V VAPOR SAVING AND) RELIEF SYSTEM 2i Sheets-Sheet 2 Filfed Jan. 15, 1958.

Patented Aug. 15, 1939 UNITED STATES- PATENT OFFICE VAPOR SAVING AND RELIEF SYSTEM Phillips Brooks Drane, Tulsa, Okla. Application January 15, 1938, Serial No. 185,243 15 Claims. (Cl. 220-) vThis invention relates to new and useful improvements in vapor saving and relief systems.

One object of the invention is to provide an improved system adapted to be applied to a battery of storage tanks, wherein oil or other hydrocarbon liquid is stored, said system being so arranged that undue waste of rich condensible vapors from the tanksvis prevented and also excessive' pressure or vacuum which may build up in the tanks is relieved.

An important object of the invention is to provide an improved system wherein a common equalizer line is connected to all of the tanks in the battery and is provided with a single relief valve, which is adapted to excessive pressure or by vacuum, whereby a proper pressure is automatically maintained in the tanks under varying atmospheric temperatures and conditions.

Another object of the invention is to provide an improved system, of the character described,

each tank having a check valve controlling the flow from said tank to the line and being normally open when the tank, to which it is applied, is closed to atmosphere; said valve automatically closing when the tank is opened to atmosphere, whereby the other tanks in the system are cut oil from the particular tank which is opened to atmosphere, which prevents the escape of vapors from the system and other tanks and results in a conservation of such vapors.

A further object of the invention is to provide an improved relief valve which is adapted to be located in the equalizer line and which is arranged to be moved in one direction by excessive pressure inthe line to relieve such pressure, and is arranged to move in an opposite direction by a vacuum in said line to admit air to the line to overcome such vacuum; the valve being so constructed that a fire arrester may be installed thereon, whereby the fire hazard to the system is reduced.

Still another object of the invention is to provide an improved check valve for a storage tank for controlling the flow of vapors from the tank to an equalizer line, said valve being associated with the usual thief hatch of the tank, whereby when the hatch is closed, the valve is open and when the hatch is swung to an open position, said valve is automatically closed to cut oil the tank from the rest of the system.

A construction designed to carry out the invention will be hereinafter described, together with other features of the invention.

be actuated by eithermcluding an equalizer line connecting the tanks;

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an example of the invention is shown, and wherein:

Figure 1 is an elevation of a plurality of oil storage tanks, havingv a system, constructed in accordance with the invention applied thereto,

Figure 2 is a partial plan view of one of the tanks, taken on the line 2-2 of Figure 1, 10

Figure 3 is a transverse, vertical, sectional view, taken on the line 3-3 of Figure 2,

Figure 4 is a horizontal, cross-sectional view, taken on the line 4-4 of Figure 3,

Figure 5 is a horizontal, cross-sectional view, 15 taken on the line 5-5 of Figure 3,

Figure 6 is a transverse, vertical, sectional view of the relief valve, ,showing the same in a closed position, v

Figure '7 is a similar view, with the valve moved 20 to an open position by a vacuum in the equalizing line,

Figure 8 is a view similar to Figure 6, showing a slightly modified form of the valve with said valve in an open position, having been moved to 25 such position by an excessive pressure within the equalizing line,

Figure 9 is a horizontal, cross-sectional view, taken on the line 9-9 of Figure 8, and

Figure 10 is a horizontal, cross-sectional view, 30

taken on the line I 0lll of Figure 8.

In the drawings, the numeral l0 designates an oil storage tank of the usual construction, which is provided with the usual hatch or access openings II in its roof. The hatch is surrounded by 35 an upstanding collar I! which is bolted to the top of the tank and a suitable closure or cover I3 is hinged to the collar I 2, being arranged to swing over the hatch or openings II to close the same. A suitable packing gasket I4, is mounted 40 in the underside'of the closure or cover l3 and engages the upper edge of the collar when the cover is in a lowered position (Figure 3). The closure may be formed with a recess I 5 for receiving lead, or other material, to add suflicient 45 weight to the closure to hold the same in a closed position. When the closure is swung upwardly to the position shown in dotted lines in Figure 3, it is manifest that access to the interior of the tank l0 may be readily had.

A plurality of the tanks III are usually located in close proximity to each. other in order to form what is commonly termed a battery. Only two of the tanks have been shown in Figure 1, but it is obviousthat any desired number may be em- 66 2 ployed. An equalizing pipe l6 extends laterally above the tanks I0 and is connected to the top of each tank by vertical branch pipes H, the upper ends of which are suitably connected with the line It, while the lower ends thereof communicate with the interior of the'tank. The oil, or other hydrocarbon liquid, in the tanks II), have vapors rising therefrom and therefore the upper end of each tank is filled with such vapors. valuable constituents and are condensible and for this reason it is desirable that the same be conserved. The vapors in the top of each tank will of course rise in the vertical pipes l1 and into the line l6 and since said line serves to connect the tanks, it will be obvious that the pressure in all of the tanks is equalized. For controlling the flow from the interior of each tank l0 into the line IS, a check valve A is interposed between the line l6 and the tanks. The valve includes a housing l8 which is provided with flanges l9 at its upper and lower end. The flange l9 rests on the top of the tank I l) and sourrounds an opening 20 which is formed in said top. A ring 2| is located within'the tank contiguous to the opening 20 and bolts 22 pass through the ring, through the top of the tank and through the lower flange IQ of the housing. These bolts receive nuts 22, whereby the valve housing is securely fastened to the top of the tank. Manifestly, the vapors from the interior of the tank may rise into the valve housing I8. The upper end of the housing has a flanged collar 23 bolted thereto and the lower end of the pipe or conductor I1 is threaded into this collar. With such arrangement, the vapors rising into the housing l8 may flow upwardly therethrough and into the conductor or pipe l'l, fronrwhich they may enter the equalizing line l6. An annular valve seat 24 is formed within the housing l8 and is adapted to be engaged by a circular valve disk or member 25. The disk is provided with a depending stem 26 and said disk is vertically movable within the housing, being guided in such movement by radial guide ribs-21, which are preferably formed integral with the housing |8. Upward movement of the valve disk is limited by an axial pin 28 which depends from a spider 29 mounted in the upper end of the valve housing. Downward movement of the disk is of course, limited by the engagement of said disk with the valve seat 24.

When the disk 25 is in a raised position, as

, shown in Figure 3, the vapors from the interior or the tank It) may flow upwardly past the valve seat and into the equalizing line i6: However, when the disk is moved downwardly to the position shown in dotted lines in Figure 3, said disk engages the valve seat 24 and shuts off the flow through the valve housing. Therefore, when the disk 25 is seated, the vapors from the other tanks in the battery cannot flow through'the conductor 11 and into the tank on which said valve is mounted.

Under normal conditions, the cover or closure I3 is in its lowered position closing the hatch or opening whereby the interior of the tank is not open to the atmosphere. At such time, it is desirable that the vapor pressure within all the tanks of the battery be equalized and for this 7 reason, it is desirable thatthe valve disk 25 be in a. raised or unseated position to permit such equalization to occur. When the cover I3 is raised or opened and air is admitted to the interior of one of the tanks through the access which may be stored These vapors contain rich and opening H, the pressure in this tank is released to atmosphere. It is desirable when said cover is raised that the. valve disk be seated so as to prevent the vapors from the other tanks and from the line Hi from escaping through the 5 opening H of the tank which is open to atmosphere. To automatically control the valve disk 25, the lower end of the stem 26 of said disk is engaged within a recess 30' provided at one end of an'operating lever 3|. The lever is pivoted at 1 32 on a bracket 33 which depends from thering 2| bolted to the underside of the top of the tank Ill. The other end of the lever 3| extends beneath the hatch or access opening I I and has the lower end of an operating rod 34 threaded there- 15 in. A lock nut 35 is screwed on the threads of the rod 34 and with this arrangement, it is evident that the relative position of the rod 34 with relation to the lever may be varied. The rod extends upwardly through the opening II and 20 within the collar l2, having its upper end engaged by the underside of the closure or cover l3.

When the closure is in its lowered or closed position, as shown in full lines in Figure 3, said cover engaging the upper end of the rod 34 swings the opening lever 3| so that the valve stem and disk 25 are raised or lifted within the casing or housing l8. The weight of the closure I3 is suflicient to overcome the tendency of the lever to swing to the position shown in dotted 30 lines in Figure 3, which tendency is due to the pivot point of said lever, as well as to overcome the weight of the valve disk and stem. Therefore, so long as the closure I3 is in a lowered position, the valve disk 25 is held in'a raised or unseated 35 position to permit a flow of vapors from. the interior of the tank upwardly into the conductor end line l6. 1

When the closure I3 is swung upwardly to the position shown in dotted lines in Figure 3, the weight of the valve disk and stem, together with the pivotal mounting of the lever, will cause the lever to move to the position shown in dotted lines in this figure. Such movement is suflicient to permit the valve disk-25 to engage the seat 24 and thereby cut ofi the flow from the conductor l! to the interior of the-tank. So long as the cover or closure is lifted and the interior of the tank is open to the atmosphere, the valve disk 25 remains seated and flow from the other 56 tanks in the battery to the open tank is cut off, whereby the vapor pressure in such other tanks is maintained. As soon as the cover is again swung downwardly to close the opening H, the lever 3| is again swung due to the engagement of the 55 underside of the cover with the operating rod 34, whereby the valve disk 25 is again raised.

When the valve disk is in its raised position, it is its the upward movement of the disk, prevents the lower end of the valve stem 2| from becoming disengaged with the recess 30 in the lever 3|.

From the foregoing, it will be seen that when 5 the cover i3 of each tank is lowered or in a closed position and the interior of that tank is not open to the atmosphere, the check valve A of that tank is open, whereby a flow through the conductor ill and line H5 is permitted. Therefore, when all of the closures or covers |3 are lowered, the vapor pressure within the entire system, thatis, within all of the tanks and the lines connecting the same, is equalized. In the event any one tank is opened to the atmosphere by lifting its 76 held in this position. In

hatch cover, that tank is automatically cut out of the system and communication between that tank and the remaining tanks is automatically shut off. This prevents any escape of vapors from the other tanks, whereby an undue waste of the rich condensible vapors is prevented.

Due to atmospheric temperatures and conditions, as well as to other causes, the vapor presmined point, said pressure will lift the valve member 4|,,whereby the ring 38 is lifted from the seat 31. When this occurs, the vapor from within the stand pipe 35 may pass upwardly past the seat and escape from beneath the cap 48. The pressure at which the valve member 4| and ring 38 are lifted is determined by the relation between weight of the ring 38 and the weight 41,

sure within the system will vary, and in some instances will cause excessive pressures, whereas in other cases a vacuum which if not relieved, would cause collapse of the tank. Therefore, some means must be provided to take care of these excessive pressure and vacuum conditions which will probably arise with changes in temperature and other conditions. For this purpose, the equalizing line I6 is extended from the last tank in the battery and is connected with a vertical stand pipe 35. The upper end of this pipe has a relief valve B mounted thereon and this valve is arranged to relieve excessive pressures which may set up within the system, as well as to take care of a vacuum, in the event the same should be formed within the system.

The valve B is clearly shown in Figures 6 and 7 and includes a cylindrical casing or housing 36, which has its lower end reduced andinternally screw-threaded so as to be threaded onto the upper end of the stand pipe 35. An annular valve seat 31 is formed within the casing 36 and a ring 38 is normally seated thereon. The ring is formed with an annular recess 39 which receives lead or other material, whereby a desired weight may be given the ring. The ring is vertically movable within the casing, being guided in such movement by vertically extending, radial ribs 40 which are preferably made integral with the casing. A circular valve member or disk 4| is located below the ring and is adapted to engage the underside thereof. The valve member is formed with upwardly extending lugs 42 which extend upwardly through the ring and these lugs serve to guide the valve member in its vertical movement, as will be explained. A link 43 has its lower end pivoted to the upper side of the valve member 4|, while its upper end is pivoted to one end of an operating yoke 44. The yoke extends radially of the casing 36 and has its outer end extending into a chamber 45 which is formed by enlarging the casing 36. Y which extends transversely of the chamber 45. The outer end of the yoke, or that portion within the chamber 45, is provided with a weight 41, which weight may vary according to the conditions, as will be explained. The open upper end of the casing 36 is covered by asuitable cap 48 which cap is supported in spaced relation from said upper end by a plurality of ribs 49 which The yoke 44 is pivoted on a shaft 46 are grooved to engage the upper edge of the casing. The vapors rising within the casing pass upwardly into the cap 48 and then escape outwardly around the lower edge thereof, passing between the supporting ribs 49. If desired, an internal annular shoulder 50 may be formed within the upper end of the casing and a suitable fire screen, or other fire arrester may be interposed between this shoulder and the lower edge of the supporting ribs 49 of the cap.

Under normal conditions, the valve member 4| is in the position shown in Figure 6, the weight 41 holding said valve member against the lower end of. the ring 38. The weight of the ring is greater than the weight 41, whereby the parts are the .event that the pressure Within the system exceeds a predeterand by varying these weights, the pressure at which said valve member is raised may be positively controlled.

In the event that a vacuum is formed in the system, it is desirable that such vacuum be relieved by admitting air to the system. In such case, when the vacuum within said system reaches a point suflicient to lift the weight 41, the valve member 4| is moved downwardly to the position shown in Figure 7, whereby it disengages the ring a v38. When this occurs, air entering beneath the cap 43 may flow downwardly through the valve casing 36 and into the system. By adjusting the weight 41, the vacuum at which the valve member 4| ismoved downwardly, may be positively controlled. With the above arrangement, it will be seen that a single valve which is operated either by. an excessive pressure of an excessive vacuum is provided. The vapor pressure within the system is thereby maintained at all times and under all conditions, the operation of the relief valve B being entirely automatic.

In Figures 8 to 10, a modified form of the valve B is shown. It may be "desirable in many instances to increase the weight of the ring 38. Such increase could be brought about by the substitution of a heavier ring but it would be preferable to use the same ring and add additional weight thereto. To accomplish this, an additional weight in the form of a disk 52 may be inserted within the valve casing between the vertical ribs 40. This weight is provided with a pair of depending legs 53 which rest upon the ring 38. The weight 52 is guided in its movement by the vertical ribs 40, as is the ring 38, and therefore said guide ribs act to prevent displacement of the supporting legs 53 from the ring 38. When the weight 52 is added, it is necessary to raise the fire arrester 5| and cap 48 and to accomplish this purpose an extension collar 54 may be inserted in the upper end of the casing 36. This extension collar receives the cap 48 and screen 5| in its upper end and serves to space these parts above the weight 52.

What I claim and desire to secure by Letters Patent is: l

1. A vapor saving and relief system adapted to be applied to a battery of liquid storage tanks including, tanks to permit equalization of the vapor pressure in the tanks, means in the line for relieving either excessive pressure or vacuum therein, and means separate from the relief means at each .tank for controlling the flow of vapor from the 3. A vapor saving and relief system including,

a battery of liquid storage tanks, each having an equalizing line connected with the" an access opening in its top, a closure for the sure in the tanks, means in the line for relieving either excessive pressure or vacuum therein, and a check valve actuated by the closure of the access opening in said tank for controlling the flow of vapor from the tank to the equalizing line.

5. A vapor saving and relief system including, a battery of liquid storage tanks, each having an access opening in its top, a closure for the opening, an equalizing line connected with the tanks to permit equalization of the vapor pressure in the tanks, means mounted in the top of each tank and actuated by the closure of the access opening for controlling the flow of vapor from the tank to the equalizing line, and a single valve in the equalizing line actuated by excessive pressure in said line to relieve said excessive pressure and also actuated by a predetermined vacuum to admit air to the line to relieve such vacuum.

6. A vapor saving and relief system including, a battery of liquid storage tanks, each having an access opening in its top, a closure for the opening, an equalizing line connected with the tanks to permit equalization of the vapor pressure in the tanks, means mounted in the top of each tank and actuated by the closure of the access opening for controlling the flow of vapor from the tank to the equalizing line, and a single valve 'mounted at the outlet end of the equalizing line and having a valve member movable in one direction by excessive pressure in the line and movable in an opposite direction by a. predetermined vacuum, whereby said valve member is moved to an open position to relieve excessive pressure and vacuum conditions in the line.

7. A vapor saving and relief system including, a battery of liquid storage tanks, each having an access opening'in its top, a closure for the opening, an equalizing line connected with the tanks to permit equalization of the vapor pressure in the tanks, a check valve actuated by the closure of the access opening in the tank for controlling the flow of vapor from the tank to the equalizing line, and: a single valve in the equalizing line actuated by excessive pressure in said line to relieve said excessive pressure and also actuated by a predetermined vacuum to admit air to the line to relieve such vacuum.

8. A vapor saving and relief system including, a battery of liquid storage tanks, each having an access opening in its top, a closure for the opening, an equalizing line connected with the tanks to permit equalization of the vapor-pressure in the tanks, a check valve actuated by the closure 'of the access opening in the tank for controlling the flow of vapor from the tank to the equalizing line, a valve housing mounted in the equalizing line and having a'valve seat therein, a weighted valve member adapted to engage said seat and being adapted to be lifted by an excessive pressure in the line to relieve such excessive pressure, and a second valvemember adapted to engage the first valve member and being arranged to be unseated by a predetermined vacuum in the line to admit air to the line and relieve the vacuum therein.

9. A vapor saving and relief system including,

to permit equalization of the vapor pressure in the tanks, a check valve actuated by the closure of the access opening in the tank for controlling the flow of vapor from the tank to the equalizing line, a valve housing mounted in the equalizing line and having an annular valve seat therein, a weighted valve member engaging said seat, and a valve disk engaging the underside of the ring and movable therewith in an upward direction, whereby said ring is unseated, the valve disk being independently movable in a downward direction to disengage the ring and permit a flow through the ring and past" the disk.

10. As a sub-combination in a vapor saving and relief system having an equalizing line, a relief valve including, a body mounted in said line and having a valve seat therein, a weighted valve ring adapted to engage said seat, the valve ring being movable vertically within the body, a valve disk underlying said ring and engaging the underside thereof and interior of the line so as to be lifted by an excessive pressure and to be lowered by a vacuum, the lifting being opposed by the weighted ring, and means for opposing the lowering of said disk whereby a predetermined vacuum is necessary to move said disk.

11. As a sub-combination in a vapor saving and relief system for a battery of storage tanks, each of which have an access opening in its top and a closure for said opening, a check valve mounted in the top of each tank and having a valve seat therein, a valve disk adapted to engage said seat, an operating member connected with the disk for controlling the seating and unseating thereof, and means secured to the member and adapted to be engaged by the closure for the access opening in the tank, whereby when the closure is covering the opening, the valve disk is unseated and when said closure is open said disk is seated to shut off the flow of vapors into the "tank from above the valve.

12. As a sub-combination in a vapor saving and relief system for a battery of storage tanks, each of which have an access opening in its top and a closure for said opening, a check valve mounted in .the top of each tank and having a valve seat therein, a valve disk adapted to engage said seat, an operating member connected with the disk for controlling the seating and unseating thereof, and means arranged betweenthe closure and member for actuating the valve disk when said closure is swung, whereby when the closure is covering the opening, the valve disk is unseated and when said closure is open said disk is seated to shut off the flow of vapors into the tank from above the valve.

13. As a sub-combination in a vapor saving and relief system having an equalizing line, a relief valve including, a body mounted in said line and having a valve seat therein, a weighted valve ring adapted to engage said seat, a valve disk underlying said ring and engaging the underside thereof and being exposed to the interior of the line so as to be lifted by an excessive pressure and to be lowered by a vacuum, the lifting being opposed by the weighted ring, and a weight for opposing the lowering of said disk whereby a being exposed to the predetermined vacuum is necessary to move said disk.

14. As a sub-combination in a vapor saving and relief system having an equalizing line, a relief valve including, a body mounted in said line and having a valve seat therein, a weighted valve ring vertically movable within the body and adapted to engage said seat, means for guiding the ring in its vertical movement, a valve disk underlying said ring and engaging the underside thereof and being exposed to the interior of the line so as to be lifted by an excessive pressure and to be lowered by a vacuum, the lifting being opposed by the weighted ring, and means for opposing the lowering of said disk whereby a predetermined vacuum is necessary to move said disk.

15. A vapor saving and relief system adapted to be applied to a battery of liquid storage tanksincluding, an equalizing line connected with the tanks to permit equalization of the vapor pressure in the tanks, means at each tank for controlling the flow of vapor from the tank to the line, and a single means remote from said tanks and connected in said line for relieving excessive pressure or vacuum therein.

PHILLIPS BROOKS DRANE.

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