US2440230A - Fill indicator - Google Patents

Description

April 20, 1948. w, BUTTNER 2,440,230

FILI.. INDICATOR Filed .my 22, 194i 2 sheets-sheet 1 April 20, 1948. w. c. BUTTNER 2,440,230

Fm. INDICATOR Filed July 22, 1941 2 Sheets-Sheet 2 /M/m w/52525? By y ls Arme/yer Patented `Apr. 20, 1918 william c. animer, winnen, nl, mmm to Bastian Blessing Co., Chicago, lll., a cor- The poration of Illinois l Application July 22, 1941, Serial No.1403,512

18Claims.

The present invention relates generally to liquefied petroleum gas dispensing systems and more particularly to that portion of the system relating to the filling and measuring of th'e amount of liquid present in a tank, including certain improvements in the construction, arrangement and machining of fittings.

' The present application is an ,improvement over an earlier flied application Ser, No. 361,682, flied Oct. 18, 1940, now Patent No. 2,400,569, granted May 21, 1946, to Harold L. Norway.

The petroleum product employed in systems with which the present invention is concerned,

is preferably of the paraln series, such as butane o or propane, or both, and the storage of this fuel is inthe form of a liquefied gas contained preferably in an underground tank where heat present in the ground, as below the frost line, assists in vaporizing the gas for use in a household appliance.

Two ways .are employed for vaporizing the gas and regulating its pressure. One way of Vaporizing the gas is the so-called "batch" system in which the vaporization is`carried on in the storage tank and the vapor'is withdrawn as a gas from th'e tank. The other way of vaporizing liqueiied gas is the so-called "ilash system in which the liquefied gas is withdrawn as a liquid from the tank and passed through a pressure reducing regulator which in connection with absorbed heat, causes the liquid to flash into gas.

The present invention may be used with eith'er system and although the two fittings embodying the features of the invention are illustrated in connection with the withdrawal of liquefied gas through a fitting that is generally exposed to atmosphere, it is preferred, as shown in our above mentioned application, to have means for the with'drawai of the gas so disposed as to be insulated from freely circulating atmosphere. The illustration made enables applicant to show how his invention may be employed with a unitary fltting secured in sealed relationship with respect to a single opening in a storage tank. yet having a large assortment of valves and controls for various purposes.

It is one of the objects of the invention to provide an improved filling arrangement for a liqueied petroleum gas system and an improved means for determining when a predetermined safety level is reached in the storage tank'during filling operations,

A further object of the invention is to provide an improved unitary fitting which' may be secured in sealed relationship with respect to an opening in the tank in one operation.

In view of the fact Vthat an overiilled tank is very dangerous for well known reasons, and devices heretoiore provided have relied upon means other than a visual indication such as a vapor return dip tube to prevent overiilling, the present invention is particularly adapted to be of as sistance with respect to this latter system to provide a visual indication to enable the operator to shut down filling operations th'e moment that the predetermined level is reached. In this conv nection a further object of the invention is to provide a'construction wherein a vapor return having a tube that extends to a predetermined maximum i111 level in the tank is not relied upon to prevent overillling but operates as a pressure equalizlng means between the replenishing tank and the storage tank, and serves as a fixed filling level indicator.

Approaehedin another way, an object of the in vention is to provide a fixed iill level indicator Awhich-utilizes the pressure equalizing conduit as a means to warn when a predetermined filling level is reached in the tank.

A further object of the invention is to provide an improved means for draining the tank of water after it has been tested hydrostatically before being released by the manufacturer for service.

A further object of th'e invention is to provide an improved unitary fitting or head for liquefied petroleum gas systems and further to provide a slip tube gauge arrangement which will not clog and can be easily manufactured and operated.

These being among the objects of the present invention, other objects will become apparent from the drawings, the description relating thereto and the appended claims.

Referring now to the drawings:

' Fig. 1 is a fragmentary vertical section taken through a portion of a unitary fitting mounted upon a riser pipe that is welded to a tank.

Fig. 2 is a section showing the improved construction of the head and the slip tube providing a non-clogging gauge construction.

Fig. 3 is a view similar to Fig. 1 illustrating another embodlment of the invention.

Fig. 4 is an enlarged section of the valved plug shown in Fig. 3.

Fig. 5 is a view similar to Fig. 1 showing another lmodification of the invention. l

In the drawing, a storage tank is indicated at l I as provided with a standpipe l I'2 that is mounted Iby a welded connection I3 v'where it extends through an opening Il in the wall of the 3 A tank II. The standpipe comprises an outer casing I5, an intermediate pipe or pipe vent tube I6, a tubular member I1 of a slip tube assembly I5 and a unitaryntting or head 2|. A flange mem,- ber I9 is employed to provide a cavity in which water will collect when the tank is inverted and an opening 20 through the casing drains water from this cavity to evacuate the tank completely,

. The casing I supports the head 2| as threaded thereto by tapered threads 22, and the vent or dip tube I5 is suspended from the head by threads 23 in a position preferably concentric to the casing I5. The space between the tube I6 and the casing I5 i's as narrow as possible, and the inside diameter of the tube I6 is as large as possible, the relative sizes being determined in relation to the amount of liquid expected to beA transmitted between them during a filling operation and the size of a deilector 24 on the tube I6 which size is such that .the deflector can be received and with- `drawn through the casing I5 as will be described later..

In this way the incoming replenishing liquid is spread out into the form of a thin, cylindrical column of liquid and the interior of the vent `tube I6 is large enough in combination with the action of the deflector 24 to prevent entrainment of splashed liquid.

The vent tube I6 extends through the hollow interior 25 of the head. 2I to connect with a lateral conduit 26 closed at its outer end by an automatic closing or stem operating vapor return or pressure equalizing valve assembly 21 such as is more particularly described in'application Serial No. 397,096 of William C. Buttner and Savin L. Sundstrom, Patent No. 2,405,998, granted August 20, 1946. The space 26 between the casing I5 and the tube I6 opens into a conduit 3 I'which is closed at its outer end by an automatic closing or stem operated illlervalve assembly 32 such as described in the above mentioned application vSerial No. 397,096. The valves 32 and 21 open when filling and vent hoses respectively, (not shown) are connected thereto, when the ilquid is being introduced into the tank.

Concentricity of the casing I5 and the tube I6 enables the operation of threading the head 2I with different threads to be performed in a single operation, both threads having the same lead.

- The vent tube I6 extends down into the tank f I'I and serves as a frictional skin carrier for the descending cylindrical column of replenishing iluid. However, for the purpose of providing a quiescent area below the mouth 33 of the tube I6.the conical bell-like defiector 24 is made of' Aa ilexible material such as Duprene and is secured to the pipe below the mouth 34 of the casing I5 in a suitable manner, as by a tight ilt as shown, or a threaded collar (not shown). In this way. the incoming stream of liquid is fanned out to such an extent that little, if any, surface turbulence is caused in the tank.

In the present invention illustrated, a liquid `e'duction tube 55 is provided inside the tube I5, close to-one wall thereof, to conduct liquefied gas out of the tank through an externally threaded boss 36 adapted to be connected toa service line (not shown) which line includes first and second stage pressure regulators and preferably a vaporizer therebetween. T'he eduction means is more specifically described in the Savin L. Sundstrom Patent No. '2,303,712 wherein a selectorvalve 3 1 and a kmanual control means 35 are more specifically described. The selector valve enables the use of the iltting in either batch or flash systems.

The slip tube gauge I5 is an improved oneas 'designed to serve several functions that otherwise cooperation with the vent tube I6 to warn when a maximum ll level has been reached, and also permits the servicing of the packing around the tube.

The slip tube gauge I8 as shown in detail in Fig.

^ 2 comprises a tubular member I1 slidably mounted to slip up' and down through the body 4I and sealed with respect to the body 4I bya packing 42 compressed by a gland nut 43. The lower end of the body is machined to provide ra valve seat 44 and is externally threaded as aty 45 with a tapered thread that is received in the top of the head 2l where it establishes a seal when tightened. The tubular member I1 comprises an.

upper pipe 46 and a lower pipe 41 both threaded into an intermediate connecting collar 45 which carries on the upper side thereof, a washer 5I engaging the seat 44 when the slip tube is raised to its upper limit. Thus, when the washer 5I is raised against the seat 44, such engagement providesa means whereby ythe compartment in which the packing 42 is located, is relieved of tank pressures so that the packing 42 can be replaced or repaired whenever desired.

The length of the lower pipe 41 is such that when the washer 5| engages the seat 44 the mouth 52 thereof is drawn up into the vent tube I6, above the intended maximum rated illl level for the tank. In fact, the mouth 452 may be disposed in the tube I6 above the level of the opening 33 so that all levels of liquid in the tank may be gauged by the slip tube when filling operations are terminated. In this way the washer 5I and collar 48 serve not only as a means whereby `the packing 42 can be replaced with safety, but also serves as a stop which determines the upper limit of movement of the slip tube gauge.

The upper end of the gland nut is provided with one of the cooperating elements o1' a bayonet joint 53, and the head 54 that is shown threaded to 'the upper end of the slip tube member 46 as at 55 is provided with the other element of the bayonet joint 53. In this way, upward creeping of the tube under vtank pressure is prevented.

The head 54 has a threaded chamber 56 therein separated from the tube 46 by a partition 51. ,A hole 58 is drilled through the partition 51 concentrically with respect to the threads in the wall of the chamber and a vent plug assembly 6I carrying a pin 62 surrounded by a washer 63 through the hole 56 which is very diflicult to obstruct vby loose particles as compared with a conventionally open small drilled hole. The pin,

by extending through the hole, also serves as a means for cleaning the hole.

` the liquid level is a condensible vapor.

limit, the vent plug u is 'loosened umu a hissing of escaped gas informs,the operator that thegauge is in operation. 'I'he tube is then pushed down slowly until liquid discharges from the vent .hole 66 at which time a reading is taken from calibrated marks (not shown) on the outer surface oi' the tube 46, and by these markings, the

'Ihe vent plug is provided with a T-handle 66" to aid in this manipulation and a protecting cap 61 is threaded to the body 4l toengage a washer 88'which closes the vent hole 1| in the body 4|. Thus, when the cap'61 isl initially loosened any discharge of fluid from the vent hole 1| serves as a warning that the slip tube gaugehas been leaking and the hole 1| vents trapped lgas under pressure which otherwise might lift the cap and cause it to strike the operator. 1

Referring now to that part of the operation of the slip tube gauge which relates to its function .as a means for determining when the maxi' mum rated level has been reached during the filling operation, it has been mentioned that the position of the slip tube gauge for this purpose is its upper limit where the mouth 52 of the gauge is disposed upwardly inside the vent tube I8 a spaced distance abovethe maximum rated level, which, in the particular embodiment illustrated, is represented by the position of'the mouth 83 of the vent tube I6 in the tank.

As preliminary to an understanding of th arrangement, it would be well to note at this time some of the physical characteristics of liquefied petroleum gaswhich have been overlooked in the design of several conventional constructions.

Tanks such as the storage tank are serviced and replenished from a supply tank on a truck. The fluid contents of. both of these tanks above The pressure existing in each tank in absence of an `additional gas such as air, is the vapor pressure of the fluid at the existing temperature, or in liquid level in the tank is determined. The vent vapor'passing up through the tube 12.

be accentuated if the supply tank is warmer than the storage tank.

In conventional systems, either the mouth of the slip tube is relied upon to contact. directly the rising liquid level in the tank, in which case splashing causes many false warnings to be made since the size of the slip tube is small enough to entrain liquid in the out-rushing gas. or, th'event tube. is separated from the slip tube in which case whichever one has the lower mouth in the tank, yfunctions first before the other completes its `intended function.

However, with the present inventiomand the arrangement made between the slip tube member and th'e vent tube. the slip tube gauge will warn the second that the hydrostatic head begins to form, if the mouth of the slip tube gauge is disposed where the hydrostatic column begins to form.

Referring now to Fig. 3 in which like numbers refer to similar parts,vthe vent return means is illustrated asincluding a tube 12 threaded as at 13 into the head 2|A in communication with' the passage 26. 'At its lower end the tube 12 carries a downwardly opening cup 14 which prevents splashed-liquid in the tank being entrained in Eduction maybe had through the passageway 18, which may be threaded (not sh'own) to receive a liquid eduction tube. Whenever the liquid eduction tube is absent and the head 2|A is employed for batch vaporization, a baille 16 is mounted between the eduction passageway 15 and the fill passageway 11 which is shown in phantom,

other words, that pressure where vaporization and condensation balance each other at the temperature of the liquid inthe tank.

Thus, when the supply tank (not shown) is connected to the standpipe by a hose, the pressures in the two tanks tend to equalize except for the hydrostatic head resulting in the difference of. the levels of thetwo bodies of liquid. This head will increase the pressure in the lower tank above the vaporization@condensation balance existing and condensation will tend to take place in the lower tank.

This result is unaffected by presence or absence of a vent tube and takes place-.whether any vent tube that happens to be provided, extends into the tank a short distance or not.

As conventionally filled and in` order to accomplish a rapid filling. the supply tank and ground tank are generally connected so that vapor displaced in the storage tank byincoming liquid will be conducted to the supply tank to replace with vapor the volume of liquid drainedv therefrom. The vent tube will ultimatelybecome a riser pipe filled with liquid having a hydrostatic head the same as that of the supply hose. From this time on, the unbalanced pressure due to the two hydrostatic or artificial heads will cause vapor trapped in the-storage tank to condense until thereis no more vapor there and the tank is filled completely with liquid. This action would so that liquid introduced into the system through' the illl opening 32 is deflected downwardly towards the tank by the baille 16 to prevent entrainment of liquid in the supply of gas going to the service line through the boss 38.

The passageway vent 28 in both embodiments is provided in the heads 2| and 2| A by means of a drill and the outer end is plugged as at 18 in` the embodiment illustrated in Fig. 1. However, inthe embodiment illustrated in Fig. 3 the outer end of the passageway 26 is threaded to receive a plug 8| which has a passageway 82 longitudinally therein receiving a Dill valve 83 seating in the plug body as at 84. The stem 85 of the Dill valve extends outwardly beyond a, plug washer 88 into a threaded cavity 81 which cavity has a bleed w opening 88 therein adapted to vent any pressure existing in the cavity 81 beyond the seal 86. The

seal plug 9|' is threaded at both ends to be received in the threading 81 but at one end carries a recess 92 which receives the stem 85 therein, and at the other end carries a stud 93 which may be used to depress the stem 85 to open the Dill valve to permit flow through a restrictor washer 94 preferably having a #54 drill hole 95 therein.

With the plug 8| disposed as described, whenever it becomes desirable to fill the tank the vapor return hose (not shown) is connected to th'e vapor return assembly 21, the seal plug 9| is 'removed and turned end for end. The stud 93 is forced against the stem to open the Dill valve. When the liquid level rises to the cup 14 the hydrostatic column immediately begins to form andv as soon as liquid is present in the passageway 26, a fog will issue from the vent hole 88 to warn the operator that th'e tank has reached the maximum V filling level. The operator who will be expected to be watching for this indication, will immediately shut down the filling system, disconnect the hoses and return the sealed plug 9| to its original position in which the Dill valve closes and the i 7 stem 85 is protectively received without actuation in the recess 92,

'I'h'us the present invention provides an improved fillingdevice which more accurately assures the correct filling of the tank in a new.

lvent pipe fills before a shutoff is h'ad, the hydrostatic head wiil immediately clear itself after the filling is completed, and the level of the liquid therein will assume the level of the liquid in the tank. Thereafter, as particularly shown in Fig. 1, the slip tube will have sufficient play between its upper limit and the level of the liquid to check accurately the level of the liquid in the tank, even though the tank is overfilled and the level of the liquid is well above the mouth of' the vent tube. In fact, the upper level of the slip tube mouth 52 being disposed 'above the opening Il, it is possible to make an accurate test as to the level of the liquid in the tank especially in those installations wh'ere shutoff conditions in the filling operations are diflicult tocontrol.

. various dispensing systems, it wil1 be apparent to those skilled in the art that various and further uses, modifications and changes may be made without departing from the spirit or substance of the 'invention set forth in the objects and th'e description, the scope of which is commensurate with the appended claims.

What is claimed is: i l. In a liquefied gas dispensing system having a tank, a standpipe comprising a unitary head having coaxial threads thereon, an outer casing secured to the larger thread and to the tank, a pipe secured to another thread and extending into the tank. to approximately the fill level thereof, means for filling the tank through the outer casing, means 'for venting the tank through the pipe,

`and level measuring means mounted in the pipe to determine the level of liquid present in the tank above the flll level.

2. In a liquefied gas dispensing system having a tank, a standpipe comprising a unitary head having spaced threads thereon, an outer casing secured to the larger thread and to the tank,.a pipe secured to another thread and extending linto the tank to approximately the fill level thereof, means for filling the tank through the outer casing, means for venting the tank through the pipe, and slip tube level measuring means mounted for movement upwardly in the pipe to a point above the mouth of said pipe to detect the level of liquid which may be present in the pipe above the fill level and including a restricted opening controlled by a valve operable to vent to the atmosphere for visual observation.

3. In combination with a liquefied gas dispensing device having a tank. a standpipe comprising a fitting having a pluraltiy of vertically spaced threads thereon of different slus, an outer casing secured to the lower thread and to the tank, a pipe secured to another thread and extending into the tank to approximately the fill level thereof, means for filling the tank through the outer casing, means for venting the tank through the pipe including a passageway through the fitting and means including ableed valve for bleeding to the atmosphere liquid present in said passageway above said fill level when the fill level in the tank has been reached. I

4. In combination with a tank for storing liquefied gas under pressure, a standpipe comprising a unitary head having a plurality of fittings thereon including a filling valve assembly. a vent return assembly andia fluid eduction conduit. an outer casing secured to the tank and receiving the head in detachable supported sealedrelgtion,

a dip pipe upon said head in communication with the vent return assembly and extending downwardly into the tank to a predetermined level when the head is mounted upon the casing, means for shielding the vent return assembly and fluid eduction conduit from fluid introduced through the filling means and means for detecting the rises above said maximum level during fillingv operation including a valve port and a valve member carrying a pin extending through the port when the valve is closed.

6. In combination, a tank for storing liquefied petroleum gas. a vent tube extending into the tank to approximately the maximum rated filling level of the tank, a fitting having an opening surrounded by a valve seat, a slip tube gauge mounted to slide up and down in the opening comprising a tube, a stop upon the tube for disposing the lower end of the tube above the maxlmum rated level, a seal on top of the stop cooperating with the seat to seal the opening, a removable stuffing box in said opening and valve means at the top of the tube for educting fluid to the atmosphere beyond the opening to determine when the liquid level in the vent tube rises above said maximum* level during filling operation.

7. In combination, a tank for. storing liquefied petroleum gas, a tube for venting the tank of vapor during filling operations and extending into the tank to approximately the maximum rated filling level of the tank including a flexible defiector on the tube, and means for venting the interior 4of said tube to atmosphere to detect the presence of liquid in said tube.

bottom of the tube and valve means for venting said passageway to the atmosphere through a predetermined restricted opening.

9. In combination with a tank for' storing liquefied petroleum gas; a fitting adapted to be received in sealed relationship with respect to an opening in said tank; and means for venting vapor from the tank'through said fitting during filling operations including a passageway, a dip tube adapted to extend into the tank to a predetermined level and locatedl in communication with said passageway, a` deflector at the bottom provided with the same lead, the larger of said threads being received upon the upper end of the casing in threaded pressure sealed relationship, a pipe secured to another thread and extending into the tank through the outer casing to approximately the fill limitthereof, means carried by the head for filling the tank through a space between the pipe and casing, means carried by the head for venting the ta'nk through the pipe, and valve means for ejecting liquid to the atmosphere when the fill level of the liquid in the tank reaches the mouth of said pipe and the liquid level in said pipe rises above said mouth.

l1. In combination, a tank for storing liquefied petroleum gas, a vent tube extending into the tank to approximately the maximum rated iill level of the tank for venting a vapor from the tank during filling operations, means for filling the tank with the injection of liquefied petroleum gas in both its liquid and vapor phases along,

the outer wall of the vent tube including a casing opening into the tank, a deflector disposed on the tube below the opening of the casing in the tank to direct the incoming liquefied gas outwardly away from the tube, and means for venting the interior of said tube to atmosphere to eject liquefied gas in the liquid phase to the atmosphere when the maximum rated filling level in the tank is reached.

12. In combination, a tank for storing liquefied petroleum gas, a vent tube extending into the tank to approximately maximum rated filling level of the tank for venting vapor from the tank during filling operations, a fitting carrying said tube, a. casing secured to the tank receiving thetube therethrough and supporting said f1tting. a deflector on the tube below the lower end of said casing, said deflector being made of a flexible material and having its maximum dimension greater than the inside dimension of the casing, the flexibility of the material permitting the deflector to be collapsed and inserted into the tank with the tube through the casing while the fitting is being secured in place, and said deflector re-assuming its form when it clears the lower end of the casing.

13. In a gage for liquefied petroleum gas tanks,

a housing adapted to carry a slidable tube and provided with an extension therebelow to form a valve seat; a slidable tube disposed through the housing: a stop ring disposed about the tube and spaced from its lower end; a gasket carried on the upper face of the stop ring, the gasket being arranged to co-act with the valve seat to forma valve which will prevent the escape of fluid aroundthe tube when the valve is closed: and a valve normally closing the upper end of the tube and arranged to be opened for the discharge o'f fluid from the tank and through the tube.

14. In combination with a tank for storing liquefied gas under pressure, a standpipe comprising a unitary head having a plurality of f1ttings thereon including a filling valve assembly and a vent return assembly, an outer casing secured to the tank and receiving the head in detachable supported sealed relation, adlp pipe upon said head in communication with the vent return assembly and extending downwardly into the tank to a predetermined level when the head is mounted upon the casing, and means for detecting the presence of liquid in said pipe at will including a slip tube gauge the inlet of which is disposed upwardly in the dip pipe above said predetermined level when the slip tube is in its fully raised position.

15. In combination with a storage vtank for storing liquefied petroleum gas, a. tubular casing extending through a wall of the tank, means for supporting the casing in permanent relation with respect to the tank, an annular depression in the wall of said tank surrounding said casing and drain means including an opening lncommunication with said annular depression extending through the'wall of said casing, said opening being so disposed as to have a portion of its contour. outwardly of the inside wall of the tank.

16. In a gage for liquefied petroleum gas tanks, a housing adapted to carry a slidable tube and provided with an extension therebelow; a slidable tube disposed through the housing; a stop ring disposed about the tube and `spaced from its lower end; a gasket disposed about said tube intermediate said stop ring and said extension, the gasket being arranged to coact with said extension and said ring to form a seal which will prevent the escape of fluid around the tube when the tube is moved upwardly to they limit of travel; and a` valve normally closing the upper end of the tube and arranged to be opened for the discharge of iiuid from the tanky and through the tube.

17. In a gage for liquefied petroleum gas tanks, a housing having an opening therethrough, a tube slidably mounted in said opening in sealed relationship, a stop member disposed about said tube and spaced from its lower end, a valve device carried by said tube and housing including a valve disc element and a valve seat element, one of said elements being located on said stop member and the other of said elements being disposed around said opening in said housing 0n the side thereof facing said stop member, said stop member and said housing closing'said valve device when the tube is moved upwardly the full limit of travel, and asecond valve device normally closing theA upper endof said tube and slidable tube disposed in said housing, packing removably received in said housing and forming a seal between the wall of said tube and said housing, a stop ring disposed about said tube at a point spaced from its lower end, a valve seat element and a valve disc element, one of said elements being disposed on the inner end of l said housing and the other on the side of said stop ring 1991115 said housing, said elements co- ,acting to form a seal Iwhen said tube is moved upwardly the limit oi travel, preventins leakv age in the event said packing is removed.

' WILIIAM C. B

Number UNITED STATE PATENTS Name Date Jay Deo. 2 9, 1936 White June 21. 1989 Thomas Bept. 5. 1939 White Sept, 10, 1940 Thomas Jan. 5, 1943

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