US 3596582 A
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Description (OCR text may contain errors)
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Primary ExaminerSamuel S. Matthews Assistant ExaminerMichael D. Harris Attorney-Huebner and Worrel ABSTRACT: A system for replacing environmental fluid in boreholes and similar fluid-confining structures for graphic and similar purposes. The system includes a c having opposite ends, a transparent fluid in the cyli piston in the cylinder adjacent to one end of the cylinder urged toward the opposite end, remotely operable flow control valve structure confining the transparent fluid within the cylinder and thereby releasably restraining the piston adjacent to said one end, a conduit extended from said opposite end of the cylinder to an area to be photographed to deliver the transparent fluid thereto upon release of the piston, and a conduit extended from said one end of the cylinder to the area to be photographed to draw environmental fluid from said area into the cylinder for replacement purposes.
Wayne L. Sayer Bakersfield, Calif. 747,969 July 26, 1968 Underground Surveys Corporation References Cited UNITED STATES PATENTS 6/1957 Laval..........................
v lllvu U IIGLCD l l  Inventor  Appl, No.
 Filed  Patented Aug. 3, 1971  Assignee  SYSTEM FOR REPLACING ENVIRONMENTAL FLUID 1N BOREl-IOLES AND OTHER FLU CONFINING MEANS 8 Claims, 2 Drawing Figs.
PATENTEU AUG 3m:
w m @l P ll-47 as IN VE N 70/? A 7TORNE V S WA YNE L. SAVER g I x g A SYSTEM FOR REPLACING ENVIRONMENTAL FLUID IN BOREHOLES AND OTHER FLUID-CONFINING MEANS BACKGROUND OF THE INVENTION The present invention relates to a system for replacing environmental fluid in boreholes and the like as required for borehole photography and as performed by apparatus of the type shown and described in US. Pat. Nos. 2,677,996 and 2,982,191. It is to be understood that the term photography," as employed herein, is intended to include the production of a viewable image whether of the light-sensitive chemical, electronic, or other form and whether such image is of relatively permanent or transient character.
The extreme environmental problems encountered in borehole photography are described in the aforementioned patents. Borehole cameras are described therein which are adapted to be lowered into a well, for example, to take a photograph therein. The cameras are of particular significance in their ability to take photographs even below the surface of opaque or translucent liquids in the well. This is accomplished by replacing the liquid in the well through which satisfactory photographs cannot be taken with a liquid or other fluid medium which is optically transparent and through which satisfactory photographs can be taken, the transparent fluid having a different specific gravity from that of the well fluid. The cameras described in the patents are suited to the purpose but the fluid displacement mechanisms thereof are subject to certain difficulties which the present invention seeks to overcome. It has been difficult to supply adequate electrical energy for dependable operation through lengthy conductors required to reach remote locations. High pressures and temperature encountered in extremely deep wells and the like have impaired proper operation.
SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved system for replacing environmental fluid in boreholes and other fluid-confining means.
Another object is to provide an improved photographic apparatus which includes a fluid replacement system and serves the same general purposes as the apparatus of the aforementioned patents.
Another object is to provide a photographic apparatus having a fluid replacement system capable of withstanding high environmental pressures.
Another object is to provide a fluid replacement system for use with a borehole camera which is of simple and economical construction.
Another object is to provide a remotely operable fluid replacement system that can be controlled by a single electrical conductor.
Another object is to provide a remotely operable fluid replacement system which has a self-contained energy source for actuating the fluid replacement operation.
Another object is to provide such an energy source in a fluid replacement system which is unimpaired by high environmental pressures and temperatures as are frequently encountered in borehole photography.
Another object is to extend the distances of which fluid replacement systems can be remotely actuated.
Another object is to provide a fluid replacement system which operates in a reliable and facile manner and is excellently suited for its intended purpose.
Further objects and advantages will become apparent in the subsequent description of the illustrative embodiment shown in the drawing.
BRIEF DESCRIPTION OF DRAWING FIG. 1 is a foreshortened longitudinal vertical section through a borehole photographic apparatus embodying the fluid replacement system of the present invention.
FIG. 2 is a fragmentary vertical longitudinal vertical section of the borehole photographic apparatus showing a succeeding relationship of the parts thereof during operation.
DESCRIPTION OF EMBODIMENT Referring in greater detail to the drawing, there is illustrated in FIG. 1 a borehole photographic apparatus 10, including a borehole camera 112 and a fluid replacement system 14, shown disposed in a borehole casing 16. The system 14 includes an inner tubular housing or cylinder 18 within which a piston 20 is freely slidable, the piston being fitted to the housing with a sliding sealing fit. Obviously, O-rings, not shown, may be used in circumscribing relation to the piston to effect such a seal. Adjacent to one end of the housing 18 is an end wall or plug 22 which is in facing relation to one end 24 of the piston 20. The end wall and the piston end and the portion of the housing 18 therebetween define a chamber 26 for containing a supply of optically transparent or clear fluid 28. The end wall 22 is provided with a valve 30 operated by a solenoid 32 controlled from above ground by a single conductor in an electrical control cable 36. This is accomplished by connecting the operating solenoid to the conductor and to ground. Whenever the conductor is energized the solenoid is actuated to open the valve. Whenever the conductor is deenergized, the solenoid is deactivated and the valve closes. The cable may also contain conductors for the remote control of the sequencing of the camera 12 from above ground or a single control conductor may be utilized for operating the solenoid and initiating a sequence of operation of thecamera, as operational circumstances may suggest.
The camera 12 is mounted within the housing 18 below the wall 22 and in spaced relation thereto to provide a passageway 38 through which the clear fluid 28 can pass to the exterior of the housing for displacing borehole liquid 40 therebelow. The lower end of the housing 18 is preferably equipped with an annular deflecting lip 42 for causing the clear fluid to be deflected across a pair of stereopticon windows 44 forming part of the camera 12 for the purpose of flushing and cleaning the same. An electric lamp 46 or other suitable source ofillumination is operatively associated with the camera 12 and wiring 47 is provided for delivering electrical power to the lamp.
The lamp 46 is mounted on a conduit 48 having at its lower end an open intake end 50 disposed below the lamp 46 in a position such that liquid or fluid drawn into the intake end is caused to flow across the lamp for flushing and cleaning the same. The conduit 48 is in communication with a cylindrical passageway 52 defined by a double wall construction resulting from concentrically arranging an outer tubular housing 54 around the housing 18. The housing 54 has the lower end thereof secured to the housing 18, as by welding or the like, and the upper end thereof closed off by an end cap 56 to which a supporting bracket 58 is fixed.
The end cap 56 defines one end of receiving chamber 60 which is in communication with the passageway 52, the other end of the chamber being defined by an end 62 of the piston 20. A ring 64 of suitable material is secured at the upper end of the housing 18 for engaging the piston end 62 and limiting the extent of sliding movement of the piston in one direction, as shown in FIG. I, travel of the piston in the opposite direction being limited by engagement of the piston end 24 with the end wall 22, as shown in FIG. 2. The end cap 56 is provided with a release valve 66 which is opened to permit the escape of trapped air and/or liquid during movement of the piston into engagement with the limit ring 64 for filling the chamber 26 with the clear fluid 28.
The lower ends of the housings l8 and 54 have secured thereto pairs of rings or cup packers 68 and 70 for engaging the casing wall and effecting a seal therewith. The rings are made of any suitable flexible material and are arcuately formed to curve downwardly so that pressure against the lower sides thereof forces them into tighter engagement with the casing wall. Such packers are well known in the art.
The piston is formed or filled with a material having a high specific gravity, for example, lead, for gravitationally pressurizing the fluid 28. Also, the supply chamber 26 is made sufficiently large to provide for displacing the necessary volume of the borehole liquid, preferably sufficient to perform the replacement function at each of a plurality of locations in the borehole. To this end, the control of the valve 30 is sequenced to permit the necessary amount of the fluid 28 to flow out and replace the borehole liquid below the apparatus, after which the valve is closed.
The camera 12 is then sequenced from above ground for taking photographs or otherwise investigating the borehole. The sequencing of the camera may also be accomplished automatically by an activation system including wires 72 and a switch 74 which is actuated by movement of the piston end 24 into engagement with the end wall 22. It is understood, of course, that the cable 36 and the wires 47 are suitably covered for protection against the environmental conditions present in a borehole and that the viewing device 12 is similarly conditioned, preferably by being fluid filled.
A suspension cable 76 is attached to the bracket 58 and to winching apparatus above ground, not shown, for raising and lowering the apparatus.
OPERATION The operation of the device of the present invention is believed to be clearly apparent and is briefly summarized at this point. In preparation for the descent into a borehole, the apparatus is inverted to cause the piston to move gravitationally into contact with the limit ring 64, the relief valve 66 being in the open condition for permitting the escape of air and/or liquid from the chamber 60 which becomes progressively smaller with movement of the piston to the limit ring. In the meantime, the chamber 26 becomes progressively larger and is filled with the clear fluid 28 by passing the fluid through the valve 30 which is placed in open condition for the purpose. After the chamber 26 has been filled, valve 30 is closed and the apparatus is raised to erect operating position by means of the suspension cable 76 and the winching apparatus, not shown. With the valve 66 closed and the cable 36 suitably connected to the control mechanisms above ground, the apparatus 10 is lowered into the borehole casing 16 and allowed to descend to the location where it is desired to view or image conditions within the borehole. During descent, the borehole liquid 40 enters the intake end 50 of the conduit 48. As the pressure increases with greater depth, the well fluid is forced into the passageway 52 and eventually into the receiving chamber 60. Under such conditions, the pressure of the borehole liquid at the viewing depth is substantially equally effective on both ends of the piston and the full weight of the piston is available for pressurizing the clear fluid 28 and forcing it out to replace the borehole liquid. lf desired, the conduit 48 and passageway 52 are also filled with the clear fluid so that there is no air trapped in the system. This is particularly desirable where extreme pressures are to be encountered.
Preferably, the apparatus is permitted to descent a slight distance past the viewing location and then pulled up slightly in order that the cup packers 68 and 70 assume the downwardly curved positions shown in FIGS. 1 and 2 for obtaining an effective seal with the interior of the casing. The aboveground controls are then operated to open the valve 30 for a predetermined amount of time and then close it. With the valve 30 opened, the fluid 28 in chamber 26 flows through the valve in response to the pressure exerted thereon by the weight of the piston 20. The fluid flowing from the chamber passes through the passageway 38 around the viewing device l2 and across the windows 44 thereof for displacing the borehole liquid 40 adjacent thereto until sufficient liquid is forced into the intake end 50 of the conduit 4%] and the passageway 52, such liquid eventually finding its way into the receiving chamber 60 which has been enlarged by downward movement of the piston. The viewing device is then sequenced for taking photographs or for viewing the borehole through the transparent optical fluid immediately therebelow. The apparatus is then moved to another location in the borehole and the process of displacing the borehole liquid with clear optical fluid and viewing therethrough is repeated until the piston engages the end wall 22. At this time, the switch 74 is closed and the viewing device is automatically sequenced, which condition may be indicated above ground by an audio or visual signal or both, after which the apparatus is withdrawn from the borehole.
The fluid replacement system of the present invention provides its own source of energy for remote operation. The energy is dependably available and uninfluenced by high pressures or temperatures. The operation of the system is dependably and easily initiated and interrupted through a single conductor from even extremely remote locations. lts simplicity enables it to be economically produced and to attain absolute reliability.
Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.
Having described my invention, what l claim as new and desired to secure by Letters Patent is:
l. A system for replacing environmental fluids disposed within boreholes comprising:
A. a substantially sealed cylinder having opposite ends;
B. a displaceable piston seated within said cylinder adjacent to one end thereof continuously urged in displacement toward the other end of the cylinder, including a pair of coaxially related faces oppositely spaced from the ends of the cylinder and defining therewithin a first and a second coaxially related chamber;
C. a transparent fluid at a first pressure substantially filling said first chamber;
D. a fluid discharge conduit communicating with said said first chamber for conducting fluid from said cylinder;
E. an environmental fluid at a second pressure substantially filling said second chamber;
F. displacement initiating means for initiating displacement of the piston comprising a selectively operable flow control valve seated in said discharge conduit adapted to be opened for accommodating a discharge of said fluid from said cylinder; and
G. a substantially unobstructed fluid intake conduit for extending from a body of environmental fluid to the second chamber for continuously maintaining the second chamber in direct communication with the body of environmental fluid for thus maintaining the pressure of the environmental fluid substantially filling the second chamber substantially equal to the pressure of the body of environmental fluid, whereby the transparent fluid is discharged through said discharge opening and the environmental fluid is delivered to the second chamber as the piston is displaced within the cylinder.
2. The system of claim 1 wherein the cylinder is by its weight urged in displacement.
3. A system for replacing environmental fluid in boreholes and the like comprising an elongated cylinder having an upper and a lower end, a weighted piston mounted in the cylinder for reciprocal movement between the ends, whereby the cylinder is divided into an upper and a lower chamber each having an axial dimension dictated by the position of the piston relative to said ends, a substantially transparent fluid substantially filling the lower chamber of the cylinder, releasable means restraining said piston adjacent to the upper end of the cylinder, an outlet conduit connected to the lower chamber having an open end externally of the cylinder beneath the lower end thereof for accommodating a discharge of the substantially transparent fluid from the cylinder, and a substantially unobstructed intake conduit in direct communication with the upper chamber and having an open end externally of the cylinder to be immersed within a pressurized body of environmental fluid whereby said upper chamber is brought into direct communication with said body of environmental fluid for conducting environmental fluid to the upper chamber for replacing the substantially transparent fluid as it is discharged from the cylinder.
4. The system of claim 3 in which said fluid within said lower chamber, the body of environmental fluid, and said environmental fluid within said upper chamber are subjected to substantially common pressure, whereby the' weight of the piston establishes a force of a magnitude sufficient for displacing the piston.
5. The system of claim 3 in which the releasable means comprises a valve mounted on the outlet conduit.
6. The system of claim 5 including electrical means operably connected to the valve controllable remotely from the valve to open and to close it whereby discharge of fluid from the cylinder can be regulated to occur in spaced increments at different positions in the borehole.
7. The system of claim 5 in which the open end of the outlet conduit is downwardly spaced from the open end of the intake conduit.
8. A system for replacing environmental fluid in boreholes and the like comprising:
A a housing adapted to, be immersed in a pressurized body of environmental fluid including an elongated cylinder having an upper and a lower end;
B.'a weighted piston mounted in the cylinder for reciprocal fluid-discharging movement between the ends thereof, whereby the cylinder is divided into an upper and a lower chamber each having a variable axial dimension dictated by the position of the piston relative to said ends;
C. a substantially transparent fluid substantially filling the lower chamber of the cylinder;
D. releasable means restraining said piston adjacent to the upper end of the cylinder;
E. an outlet conduit connected to the lower chamber having an open end externally of the cylinder beneath the lower end thereof for accommodating a discharge of the substantially transparent fluid from the cylinder as the piston is moved toward the lower end of the cylinder; and
F. means establishing a substantially direct communication between the upper chamber and said body of environmental fluid for accommodating a passage of environmental fluid from said pressurized body to the upper chamber for replacing the substantially transparent fluid in the cylinder as the piston is moved toward the lower end of the cylinder.