US3093996A

US3093996A - Drilling pressure control assembly tester

Info

Publication number: US3093996A
Application number: US16857A
Authority: US
Inventors: Marvin R Jones
Original assignee: Cameron Iron Works Inc
Current assignee: Cooper Industries LLC
Priority date: 1960-03-22
Filing date: 1960-03-22
Publication date: 1963-06-18
Anticipated expiration: 1980-06-18

Description

June A18, 1963 M. R. JoNEs 3,093,996

DRILLING PRESSURE CONTROL ASSEMBLY TESTER Filed March 22, 1960 2 Sheets-Sheet 1 /90 f' /3 M ,Ga

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INVENTOR. x

ATTO/PNEJ/J June 1`8, 1963 M. R. JONES DRILLING PRESSURE CONTROL ASSEMBLY TESTER Filed March 22, 1960 2 Sheets-Sheet 2 Marv/f7 /0/7er INVENTOR.

ATTOR/VEK United States Patent Oce 3,093,996 Patented June 18, 1963V Texas Filed Mar. 22, 1960, Ser. No. 16,857 1'7 Claims. (Cl. 721-46) This invention relates to a device for testing ya well drilling pressure control assembly. More particularly, it relates to a device for pressure testing the sealing efficiency and the seals between blowout preventers, between a 'blowout preventer and a casing head, and -between a casing head and casing, the device being so constructed as to permit the use of relatively low pressure gas as a test fluid.

In well drilling operations, formation pressures are ordinarily controlled by the drilling fluid. However, in the event the formation pressure becomes greater than the head pressure of the drilling uid, a blowout is apt to occur. To guard against this difficulty, wells are equipped with drilling pressure control assemblies which are operable to seal the well olf and prevent blowouts.

Drilling pressure control assemblies -generally include one or more blowout preventers which are connected to the well through a casing head or the like. A blowout preventer comprises a valve-like body hav-ing rams or other sealing means operable to -seal about a drill pipe or other object in the bore of the preventer to prevent the well pressure from blowing out through the casing. Such equipment is emergency equipment and may never be required during drilling of a well; however, it is necessary to determine that the equipment is in proper condition to meet such emergencies in the event they do arise.

Occasionally, `drilling -pressure control assemblies will fail to contain formation pressures during an emergency, and, as a consequence, the well gets out of control. Generally, this 4loss of control occurs because some element of the assembly leaks and all 4attempts to stop the leak fail. When this happens, the high velocity flow of gas or abrasive particles in the gas enlarge the leak and may cut the whole assembly away. Although visu-a1 inspections, maintenance programs and the like tend to reduce the likelihood of failures during an emergency, it is considered necessary to periodically pressure test the assembly to determine that it will not leak when subjected to the highest formation pressure which `may be encountered.

One type of device known and used for testing drilling pressure control assemblies is shown in the patent to Christensen 2,540,322, This device utilizes mud as a testing agent and is designed to expose the blowout preventer and its connections to mud under high pressure without subjecting the well formation to such test pressure. An advantage of this type of tester is considered to be the fact that it utilizes la fluid such as drilling mud, which is ordinarily 'found at a drilling site, and further, such Huid may be yfurnished to the tester at a desired high pressure by conventional drilling equipment, such a-s a mud pump. However, a lleak which will permit the passage of gas will not necessarily leak mud even though the mud is ata high pressure, and drilling pressure control assemblies are required to control gas, as well as mud, when operated to prevent a blowout. Therefore, in actual practice, devices such as shown in Christensen 'are obviously unsatisfactory as pressure testers for determining that the emergency equipment is in proper condition to control a well and prevent a blowout.

Clear water, of course, leaks more readily than mud, and accordingly it has been proposed that clear water,

rather than mud, be used as -a testing fluid in testing devices of the type shown in Christensen. Although improved results are obtained, still such results are considered unsatisfactory since gas :also leaks far more readily than clear water. F or example, an assembly which may not show leakage of water at a pressure as high as 6,000 p.s.i. may leak gas readily at a pressure as low as p.s.i. Various agents have been added to the water in an attempt to overcome this diliiculty. For example, dyes have been added to the water to aid in leakage detect-ion, and surface tension reducing agents have been added to increase the likelihood of leakage. Although such changes provide still further improved test results, the ability of the control asembly to control a well and prevent a blowout during an emergency cannot be determined -since possible leaks in the equipment which would permit passage of gas at high pressure still cannot be detected.

It would be desirable to utilize gas as a test fluid since it would then be possible to ascertain the performance of the control equipment under actual operating conditions encountered during an emergency. The testing device shown in the patent to Allen 2,334,303 exempliies testers utilizing gas as a testing agent. While such devices are useful for the detection of high pressure gas leaks, they have some disadvantages because of certain characteristics inherent in their construction and operation. For example, testing devices of this type utilizing gas as a test fluid are considered objectionable because of the large amount of energy which is stored in the drilling pressure control assembly when it is full of gas at high pressure. In addition, in order to compress the large amount of gas required by these devices within reasonable time, special gas compressing equipment must be provided which is not otherwise required in connection with drilling operations, This involves a large investment in such special equipment, and in -addition constitutes a hazard to the safety of both the operators and the other drilling equipment.

An object of this invention is to provide a testing device for 4drilling pressure control assemblies which will obviate the foregoing difficulties.

Another object of the invention is to provide a testing device for drilling pressure control assemblies that retains the desirable features of known testing devices, but avoids the undesirable features of these devices.

Another object of the invention is to provide a testing device for drilling pressure control assemblies which utilizes gas as a test fluid and does not require special auxiliary equipment not otherwise used in the drilling oper-ations.

Another object of the invention is to provide a tester for drilling pressure control assemblies that does not require the storage of a large amount of energy in the assembly when testing it at high pressure.

Another object of the invention is to provide a tester for drilling pressure control assemblies which does not constitute a hazard to the safety of either the operators gr the drilling equipment when gas is used as a testing uid.

Another object of the invention is to provide a blowout preventer tester which is capable of 'detecting leaks which may occur under actual operating conditions.

Another object of the invention is to provide a tester for a blowout preventer which utilizes gas as a test iluid wherein the amount of gas required is relatively small as compared to testers presently known.

Another object of the invention is to provide a blowout preventer tester Iwhich utilizes gas as a testing iiuid to test the sealing eiciency of the blowout preventer and the connections between the blowout preventer and a well casing wherein gas may be injected at a relatively 3 l low pressure into a test space provided in the bore of the blowout preventer and subsequently increased to a relatively high pressure while confined in the test space for testing purposes.

Another object of the invention is to provide a -blowout preventer tester utilizing relatively low pressure gas as a test fluid, the tester being operable in response to fluid pressure supplied thereto from conventional well drilling equipment to increase the pressure of the gas, while it is confined in a test space in the blowout preventer, to thatnormally encountered in actual emergency conditions for testing the preventer for leaks.

Other objects are inherent and will become apparent upon consideration of the following description taken in connection with the accompanying drawings wherein certain embodiments of the invention are described and shown for purposes of illustration.

These and other objects are accomplished in this invention by a tester comprising a body adapted to provide a test space in the bore of the drilling pressure control assembly for receiving test gas, which may be at relatively low pressure such as is ordinarily available at a drilling site, and a fluid chamber for receiving operating fluid under pressure, which may be drilling mud, water, oil or the like, ordinarily available at a drilling site, and which may be provided at a desired pressure by conventional drilling equipment such as mud pumps. The gas in the test space is exposed on one side to the control assembly. connections and seals being tested, and is connected on another side with the operating fluid in the fluid chamber, whereby operating fluid may be supplied under pressure to the fluid chamber through operating fluid supply means to increase the pressure of the test gas confined in the test space for testing the assembly for leaks.

In one form of the invention, pressure responsive means is carried by the body interposed between the test gas and operating fluid, the pressure responsive means being adapted to provide a fluid-tight pressure responsive connection between the test gas and operating fluid, whereby the pressure responsive means is operable in response to operating fluid supplied thereto under pressure through the operating fluid supply means to increase the pressure of the test gas confined in the test space without requirement of direct contact between the test gas and operating fluid.

By providing for pressure responsive means interposed between and separating the test gas and operating fluid, the pressure of the test gas can be increased without danger of undesirable side reactions, such as formation of emulsions, solutions, or the like between the test gas and operating fluid, which could otherwise occur if direct contact ybetween these fluids is permitted. Of course such side reactions could interfere with or even preventdetection of leaks in the control assembly. Thus, the pressure responsive means in this form of the invention not only provides means for increasing the pressure of the test gas, but it also provides means for obtaining accurate test results when using any readily available test gas and operating fluid, even though these fluids may be of a nature such that they would normally react, when in direct Contact, in a manner to interfere with or prevent detection of leaks in the assembly. In addition, the pressure responsive means will be seen to provide means for preventing operating fluid from overflowing into the gas test space and coming into contact with the connections being tested.

On the other hand, it should be understood that the.

pressure responsive means is not necessary in order to obtain accurate test results with the tester ofthis invention. That is, by selecting a test gas and an operating fluid which do not enter into undesirable side reactions under conditions of use in the tester, and by operating the tester in a careful manner so as to avoid overflowing of the operating fluid, the pressure responsive means can be eliminated and the pressure of the test gas increased by direct contact with the operating fluid.

In one embodiment of the invention utilizing pressure responsive means, the body includes a cylinder sized for a loose fit in the bore of the drilling pressure control assembly and sealing means carried by the cylinder for sealing off the bore through the control assembly providingl a test space therein exteriorly of the cylinder. Pressure responsive means, comprising a floating piston is carried in the bore of the cylinder, the cylinder bore on one side of the piston being connected with the test space exteriorly of the cylinder, and the cylinder bore on the other side of the piston being closed and connected with means for supplying operating fluid under pressure to the piston.

When the tester is in operable position sealing off the bore through the drilling pressure control assembly, relatively low pressure test gas may be injected into the test space through passageways which are ordinarily provided in the walls of the blowout preventers, casing head, or other element of the control assembly. Inasmuch as the floating piston in the cylinder is exposed on one side to the pressure of the gas in the test space, the piston will be moved in the bore of the cylinder in a direction away from its connection with the test space. At this point, test gas at substantially its supply pressure will be confined in a space in the bore of the control assembly, said space having a total volume comprising substantially the sum of the volumes of the test space exteriorly of the cylinder and the bore in the cylinder above the piston. Operating fluid, such as drilling mud, may then be supplied through the operating fluid supply means to the other side of the piston under sufficient pressure to move the piston against the relatively low pressure test gas confined in the test space and bore in the cylinder. This reduces the total volume of the gas and increases its pressure within the bore of the control assembly. The control assembly may then be inspected for leaks.

Thus, as will be explained in more detail below, the tester of this invention is so constructed to permit the use of gas at relatively low pressure as a test fluid. Therefore, special and expensive gas compressing equipment for supplying large volumes of test gas at high pressure is not required. Further, the pressure of the test gas may be increased, while it is confined in the bore of the control assembly, for testing the control assembly for leaks under operating conditions by use of liquids ordinarily found-at a drilling site and supplied under pressure by conventional drilling equipment. Thus, it will be seen thata tester is provided which retains the desirable features of presently known gas and liquid pressure testers, but avoids the difficulties and disadvantages encountered in the use of these known devices.

For a more detailed description of the invention, reference is now made to the drawings, wherein like figures are used to designate like parts and certain embodiments of the invention are shown for purposes of ilustration. In the drawings:

FIG. 1 is a side elevation in cross section of an embodiment of the tester of this invention shown in operable position in the bore of a typical drilling pressure control assembly, the elements of the control assembly being schematically shown and the tester being adapted to form a seal with the inner surface of the casing head,

r whereby the lowermost connection to be tested is the connection between the lower blowout preventer and casing head; and

`FIG. 2 is a view similar to FIG. l except that the tester is modified to form a seal with the inner surface of the casing, whereby the lowermost connection to be tested is the connection between the casing head and casing.

In the drawings, a conventional well drilling pressure control assembly, indicated generally at 12, and comprising an upper, middle and lower blowout preventer,

13, 14 and 15, respectively, is shown connected at its lower end to a well casing 16 through a casing head 17, and connected at its upper end to other well head equipment, for example, bell nipple 19.

A vertical bore, indicated generally at 11, and comprising

bores

13a, 14a and 15a in the upper, middle and lower blowout preventers, respectively, together with bore 19a in bell nipple 119, bore 17a in casing head 17, and bore 16a in surface casing 16, provides access to the well formation for drill bits, drill pipe, casing, tubing and the like which are used in the drilling and completion of the well.

A seal ring 20 surrounds bore 11 at each of the anged connections between bell nipple 19 and preventer 13, between

preventers

13, 14 and 15, and between preventer 15 and casing head 17, while casing head 17 is sealably and removably connected to casing 16 as by threaded connection 21. As is the usual practice, the flanged connections are provided with suitable means, such as llange studs and nuts (not shown), for pulling the anged connections together into sealing relationship. Thus, in the event the Vhydrostatic head `of the drilling mud is not suicient to control the gas pressure in the well formation, the well can be sealed off to prevent a blowout by providing a seal across bore 11 by closing a blowout preventer. j

' Of course, an emergency such as a threatened blowout of a wellmay occur at any stage of the drilling or completing operation, and accordingly, bore 11 may contain objects such as drill pipe, casing, tubing and the like, which is being used in the well at the time the emergency arises. Thus, it is necessary to provide means for seal-A ing olf the annular space in the bore 11, between the object contained therein and the casing 16 to prevent iluid from blowing tout therethrough.

For this purpose, it is conventional practice to provide each of

preventers

13, 14 and 15 in the control assembly with sealing means, such as opposed rams 18, operable to seal about the object in the bore for sealing the well olf and preventing a blowout. Since the drilling mud may have been blown out of the well or become gas cut by the formation gas when the control assembly is operated to prevent a blowout, the seal formed between the4 rams and the object in the bore, as well as the connections between the various elements of the control assembly and casing, all may be subjected to gas at substantially its formation pressure. That is, during an emergency, each of seals 20 at the connection below the rams, connection 21 and the rams themselves, may be exposed to gas under for-mation pressure, and therefore, for the reasons previously given, it is considered necessary to periodically gas pressure test the entire drilling pressure control assembly to ascertain the pressure that the assembly will hold without leaking.

` At this point, and before proceeding to a detailed description of the tester of this invention, it should be noted that the above described well drilling pressure control assembly Iand associated elements is intended merely as an illustration of a typical installation of this type of emergency equipment, zand that other arrangements and elements are known and used for this purpose. Further, it is to be understood that the tester of this invention can be used to advantage in testing control assemblies other than the typical installation here illustrated.

IIn the tEorm illustrated in FIG. 1, the tester of this invention indicated generally at 110, comprises a cylinder 22 formed on a diameter slightly smaller than the diameter of bore 11, adapting the tester to be inserted into operative position in thel bore of the control assembly 1,2, and to pnovide a relatively small annular test space Z8 therein exteriorly of cylinder 22. Cylinder 22 has a -bore 2.3` therethrough and is open 4at its upper end 24 to passage of gas between bore 23 and test space 28, and i-s closed atl its lower end to passage of iiuid by adapter plug Z5, which is preferably removably and sealably connected to surface of casing head 17 and plug 25 for sealing olf bore 1:1 below the lowermost connection seal 20 to be tested, and dening the lower boundary of annular test space 28.

The upper boundary of test space 28 -is defined by the seal yformed when rams 18 of the upper blowout pre-Venter l13 engage ram receiving surface 30 on the outer surface of operating iiuid supply conduit 31. Thus, it will be seen that when the tester 10` is in operative position in the bore of the control assemlbly 12, the bore 11 is sealed oi and a relatively small annular test space l218 is provided therein exten'orly of cylinder 22 for receiving test gas under pressure `from a suitable source (not shown) through a gas 'supply conduit 33a and side opening 3x2 in blowout preventer 13, the gas flow through conduit l33a being controlled by a suitable means such as valve 33.

One of the novel features of the tester of this invention, contrary to Ipresently known testers using gas as a test fluid, isthat the test gas need not be supplied to the control assembly at its relatively high testing pressure, but nather can be injected into the test space of the control assembly at a relatively low pressure, such as is ordinarily available at a drilling site, and then increased in pressure while confined in the test space to test the control assembly for leaks under operating conditions.

For this purpose and to provide means for separating and preventing direct contact between the test gas and operating fluid, pressure responsive means comprising an annular lloating piston 34 (shown in solid lines at an intermediate position) is carried in the bore 213 of cylinder 22' and is movable therein in response rto lluid pressure supplied thereto between a lirst position near the lower closed end of the cylinder (shown in dotted lines) and -a second near the upper open end olf the cylinder (also shown in dotted lines). Piston 34 is provided with sealing means for forming a seal between the operating iluid supply conduit 3|1 and the inner surface of cylinder 22, adapating the piston lfor dividing bore 23 into an upper gas chamber 35 and -a lower liquid or lfluid chamber 36.

Piston 34 may be of any suitable construction and is shown here as fbeing `formed from resilient material such as rubber, Hycar, or the like, and has annular U-shaped grooves 36 .and 37 in its upper and lower faces, respectively, forming upper and lower lips 318 and c39 on the outer diameter of the piston and upper and

lower lips

40 and 41 on the inner diameter of the piston for slidably engaging the inner surface of the cylinder v22 and the outer surface of conduit 3-1, and forming a pressure energized type seal therebetween. Thus, in its upper position, piston 34 also limits the upward movement of operating uid within the cylinder and prevents the operating fluid from overllowing into the test space exteriorly of the cylinder.

Operating fluid for moving piston 34 is supplied thereto through operating lluid supply conduit 31, which is preferably removably connected at one end, as by threaded connection 42, to adapter plug 25 'and extends upwardly therefrom axially of bore 23 and beyond the upper end of cylinder 22. The other end of conduit 3-1 is connected through control valve 43 and supply line 44 to a source, such las -a mud pump (not shown), remote from the control assembly `for providing operating fluid at the desired pressure. Passage means 45 is yformed in adapter plug 25 and connects the passageway through conduit 31 with liquid chamber 36, jected from conduit 311 into liquid chamber 536 and against the undeside of piston 34 under suicient pressure to move the piston upwardly from its lirst to its second position.

As previously mentioned, piston l34 may be eliminated and the tester operated without pressure responsive means interposed between and separating the test gas and operating fluid. In this form of the invention, the pressure p of the test gas is increased by pumping operating tluid whereby operating luid may be ininto the tester and'directly against the test gas. Accordingly, when operating the tester without the piston, the nature of the test gas and operating fluid should-be such that they ydo not tend to emulsify, form a solution, or otherwise react in a manner to adversely affect the test results.

It will also be understood that inasmuch as the piston is not being used, care should be exercised in pumping operating fluid into the tester, particularly if the pressure of the test gas in the test space in being usedas a control for limiting the amount of operating fluid being introduced. That is, since the piston is not present to limit the upward movement of the operating fluid in the cylinder, sufficient operating fluid could be pumped into the cylinder to cause an overfiow into the test space in the event a leak at some point in the control assembly prevents normal build-up of pressure in the test space. Accordingly, when operating the tester without the piston, it is preferable to control the tester by regulating the quantity of operating fluid being introduced by any suitable means such as a flow regulator (not shown).

Although the operation of the tester of this invention will no doubt be apparent from the foregoing description, its operation will be clearly understood in View of the following described test performed on a typical drilling pressure control assembly.

According to the usual practice, the control assembly is first emptied of all tools and is carefully cleaned so that -any leaks which may develop during the test may be more easily detected. A tester sized to fit the particular control assembly being tested is `then inserted into the bore of the assembly so that its lower end seats and forms a seal in the casing head below the lowermost connection to be tested. The rams of the uppermost blowout preventer to be tested are then closed to seal about the operating liuid supply conduit. At this point, the bore through the control assembly is sealed off and a relatively small annular test space is provided in the bore of the assembly exteriorly of the cylinder. The upper and lower boundaries of this test space are defined by the ram seal and casing head seal, respectively, and each of the connections therebetween are exposed to the pressure in the test space. In addition, the control valve in the operating fluid supply conduit is opened to atmospheric pressure.

The annular test space is then precharged with test gas at any desired pressure, for example, the relatively low pressure at which the gas is ordinarily provided at a drilling site. This may be accomplished by opening the valve in the test gas supply line and allowing the gas to flow into the control assembly until fiow stops and the pressure within the assembly counterbalances the supply.

pressure. It will be recalled that the cylinder is opened at its upper end to passage of gas and at its lower endA to atmosphere, and therefore, the piston in the cylinderk will be moved downwardly to its first position near the bottom of the cylinder. The v-alve in theV test gas supply line is then closed. At this point, test gas at substantially its supply pressure completely fills and is confined in the test space eXteriorly of the cylinder and in the gas chamber within the cylinder and `above the piston.

The control valve in the operating fluid supply conduit is then positioned for supply from the mud pump and 1 operating iiuid is pumped through the supply conduit and passage means in the adapter plug and into the liquid chamber below the piston. Of course, the mud pumps ordinarily used in the drilling operation can easily provide operating fluid under sufficient pressure to move the piston upwardly against the pressure of the test gasto the top of its stroke near the open end of the cylinder.

This upward movement of the piston reduces the total.

volume of the test gas and correspondingly increases its pressure. When the piston reaches the top of its stroke, the control valve in the supply conduit is closed and the control assembly is inspected for leaks by any known means, including observation of decline of pressure as 8; shown on a guage. After the inspection is completed, the tester may be removed from the control assembly by reversing the foregoing procedure.

Referring now to FIG. 2, it will be seen that this form of the testerl of/thisinvention is the same in all respects as the tester of FIG. l, except that the tester of FIG. 2 has been modified to form a seal in the bore of the casing 16 rather than in the bore of the casing head 17 so that the connection between the casing head and the surface casing is the lowermost connection to be tested.

Thus, in the form shown in FIG. 2, adapter plug 25a does not form a seal with casing head 17b, but rather merely engages the inner surface 17a of the casing head for supporting the tester in the bore of the control assembly. A stinger 50 is preferably removably connected to adapter plug 25a, as by threaded connection 51 and carries a pressure energized type seal such as O-ring 52 for forming a gas-tight seal about the inner surface of casing 16.

The operation of this form of the invention is the same in `all respects as the operation =of the tester of FIG. 1 except that the test gas is precharged through a side opening 53 in casing head 17b through gas supply conduit 54.

and control valve 55. However, it will be understood that test gas may be precharged through a side opening in one of the blow-out preventers similarly as was provided in the example of FIG. 1.

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

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

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

The invention having been described, what is claimed 1. A device for testing a drilling pressure control assembly including a blowout preventer connected to a surface casing through a casing head or the like, the control. assembly Ihaving means for charging tes/t gas under pressure into the bore thereof and sealing means carried by the blowout preventer operable to seal about an object in the bore, said testing device comprising abodyV the body bore land a second position further removed, therefrom and near the open end` thereof; said piston beingmovable from said second to said first position when said test space is precharged with test gas under pressure; and means` for supplying operating fluid under pressure to said, floating piston for moving it Afrom said first to saidl second position and increasing ther pressure of the gas confined in said test space,

2. Atesting device according to claim 1 wherein said sealing means carried by thebody comprises a surfaceI at the upper end of the body for sealablyl receiving the blowout preventer sealing means and additional means for forming a seal between the body and the inner surface of the control assembly below the Iowermost connection to Abe tested.-

3'. A testing device according to claim 2 wherein said body is stepped on different diameters, the body portion having smaller diameter providing said surface for receiving the blowout preventer sealing means, and the body portion having the larger diameter being formed on a diameter slightly -smaller than the diameter of the bore through the controlassembly to provide an annular test space `in the blowout preventer bore exteriorly of the body, said annular test space being relatively small with respect to the bore in said body.

4. Adevice for testinga'drilling pressure control assembly including one or more blowout preventers connected to a well casing through a casing head or the like, the assembly having a vertical boretherethrough and the blowout preventers having rams operable to seal about an object in the bore, said testing device comprising, a cylinder formed on a diameter slightly smaller than the diameter of the bore through the drilling pressure control assembly, said cylinder being closed at its lower end and open at its upper end; an operating fluid supply conduit connected to the cylinder at the closed end thereof and extending through the bore of the cylinder and beyond the open end thereof, the portion of said conduit in the bore of the cylinder being sized to provide an annular space therein, and the portion of said conduit exteriorly of the cylinder being sized to provide a surface for receiving the rams of the blowout preventer; an annular floating piston in said annular space in the bore of the cylinder movable therein in response to fluid pressure between a first position near the closed end of the cylinder and a second position further removed therefrom and near the open end thereof; means connecting the passageway through said operating fluid supply conduit and the annular space in the cylinder for supplying operating liuid under pressure to said annular floating piston for moving the piston from said first to said second position; and means for forming a seal between said cylinder and the inner surface of the drilling pressure control assembly below the lowermost connection .to be tested.

5. A device for testing a drilling pressure control assembly including a plurali-ty of blowout preventers connected to a well casing through a casing head or the like, the assembly having means for charging test gas under pressure into the bore thereof and the blowout preventers having rams operable to seal about an object `in the bore, said testing device comprising, a cylinder formed on a diameter slightly smaller than the diameter of the bore through the drilling pressure control assembly for providing a relatively small annular test space in said assembly bore exteriorly of the cylinder when the tester is in operative position therein, said cylinder being closed at its lower end and open at its upper end to passage of gas between the bore of the cylinder and said test space exteriorly of the cylinder; an operating fiuid supply conduit having a passageway .therethrough and extending axially through the bore of the cylinder and beyond the open end thereof, one end of said conduit being connected to the cylinder at the closed end thereof and the other end of the conduit being connected with a source remote from the control assembly for providing operating Huid under pressure, the portion of said conduit in the bore of the cylinder being sized to provide an annular space therein, and the portion of the conduit exteriorly of the cylinder being sized to provide a surface for receiving and forming a seal with the rams of the upper blowout preventer and defining the upper boundary of said test space; an annular fioating piston in said annular space in the bore of the cylinder movable therein between a first position near the closed end of the cylnder and a second position near the open end thereof; sealing means carried by said piston for forming a seal between the outer surface of the conduit and the inner surface of the cylinder adapting the piston for dividing the annular space in the bore of the cylinder into an upper gas chamber and a lower operating fluid chamber; means for forming a seal between the cylinder and the inner surfaceof the drilling pressure control assembly below the lowermost connection to be tested and defining the lower boundary of said test space; said floating piston being movable to said first position upon the introduction of test gas under pressure into said test space and gas chamber; and passage means connecting the passageway through the operating liuid supply conduit and said lower operating fluid chamber for supplying operating fluid under suilicient pressure to move the annular floating piston from said first to said second position for increasing the pressure of said test gas and testing the connections of the control assembly and the sealing efiiciency of the rams.

6l. A testing device according to claim 5 wherein said conduit and cylinder are sized to provide a relatively large annular space within the cylinder with respect to said annular ltest space exteriorly of the cylinder for providing a relatively large increase in pressure of the test gas when said piston is moved from the first to the second position.

7. A testing device according to claim 6 wherein said sealing means carried by the piston comprises a pressure energized seal.

8. A tester according to claim 7 wherein the closure at the lower end of said cylinder comprises an adapter plug releasably connected to the cylinder at its lower end.

9. A tester according to claim 12 wherein said conduit is releasably connected to said adapter plug.

10. A tester according to claim 9 wherein said passage means connecting the passageway through the conduit and the operating fluid chamber comprises a passageway formed in said adapter plug.

1l. A testing device :according to claimlO wherein said means for forming a seal between the cylinder and the inner surface of the control assembly comprises sealing means on the adapter plug for forming a seal between the adapter plug and the inner surface of the casing head yadjacent the connection between the casing head and lower blowout preventer.

12. A testing device according to claim ll0 wherein said means for forming ya seal between the cylinder and the inner surface of lthe assembly includes la stinger carried by the adapter plug and `sealing means on the stinger for forming 1a seal between the stinger and the inner surface of the well casing adjacent the connection bet-Ween the casing head `and lwell casing.

13. A testing device according to claim. l2 wherein said stinger is releasably connected to the adapter plug.

14. For use in testing 4a blowout preventer having a bore therethrough and means for introducing a test gas into the bore, a device comprising ya hollow body adapted to fit closely within the bore to provide an annular test space to be charged with said test gas, one end of said body being closed to define 4a fluid chamber therein communicating at its other end with said -test space and being relatively large in ycomparison to said test space, and means connecting with the closed end of said body for supplying operating liquid to said uid chamber to increase the pressure of the gas in said test space, the closed end of the body being lower than the opposite end thereof so that the operating liquid flows upwardly into the chamber ,as it is supplied thereto.

15. A device of the character defined in claim 14, including a member extending across .the chamber to separate the operating liquid from the test gas and movable therein responsive to said liquid for increasing the pressure of said test gas.

16. A device of thecharacter defined in claim 15, wherein said supply means comprises :a conduit extending downwardly through the 4fluid chamber and defining an annular `space between the conduit and chamber, and the separating member extends across the annular space.

17. A device for testing a drilling pressure control assembly including a blowout preventer connected to a surface casing through -a casing head or the like, the control assembly having means `for charging test gas una bore insaid body, one end of the body bore being closedV and the other end being connected with said test space and open to passage of uid therebetween when the tester is in operable position in the bore of the control assembly; a pressure responsive member extending across the bore ofthe body and movable therein between a rst position near the closed endof'v the4 body bore anda second position further removed'therefrom and'near the open end thereof, and -means for supplying operating, uid under pressure to said member. for movingtit from said rst to said second positionfand increasing the :pressure of the gas conned insaid test space.

References Cited inthe le of this patent UNITED STATES PATENTS 1,744,698 Granger Jan. 271, 1930 2,478,628 Hansen Aug.` 9; 1949 2,652,717 Bush-etfal. Sept. 22, 1953 2,662,393 Rzasa, Dec. 15, 1953

Claims

17. A DEVICE FOR TESTING A DRILLING PRESSURE CONTROL ASSEMBLY INCLUDING A BLOWOUT PREVENTER CONNECTED TO A SURFACE CASING THROUGH A CASING HEAD OR THE LIKE, THE CONTROL ASSEMBLY HAVING MEANS FOR CHARGING TEST GAS UNDER PRESSURE INTO THE BORE THEREOF AND SEALING MEANS CARRIED BY THE BLOWOUT PREVENTER OPERABLE TO SEAL ABOUT AN OBJECT IN THE BORE, SAID TESTING DEVICE COMPRISING A BODY SIZED FOR A LOOSE FIT IN THE BORE OF THE DRILLING PRESSURE CONTROL ASSEMBLY; SEALING MEANS CARRIED BY THE BODY FOR SEALING OFF THE BORE THROUGH THE CONTROL ASSEMBLY AND PROVIDING A TEST SPACE THEREIN EXTERIORLY OF THE BODY; A BORE IN SAID BODY, ONE END OF THE BODY BORE BEING CLOSED AND THE OTHER END BEING CONNECTED WITH SAID TEST SPACE AND OPEN TO PASSAGE OF FLUID THEREBETWEEN WHEN THE TESTER IS IN OPERABLE POSITION IN THE BORE OF THE CONTROL ASSEMBLY; A PRESSURE RESPONSIVE MEMBER EXTENDING ACROSS THE BORE OF THE BODY AND MOVABLE THEREIN BETWEEN A FIRST POSITION NEAR THE CLOSED END OF THE BODY BORE AND A SECOND POSITION FURTHER REMOVED THEREFROM AND NEAR THE OPEN END THEREOF, AND MEANS FOR SUPPLYING OPERATING FLUID UNDER PRESSURE TO SAID MEMBER FOR MOVING IT FROM SAID FIRST TO SAID SECOND POSITION AND INCREASING THE PRESSURE OF THE GAS CONFINED IN SAID TEST SPACE.