US3788073A - Apparatus for applying a substantially constant tension to an elongated member connected to an installation subject to alternating movements - Google Patents

Apparatus for applying a substantially constant tension to an elongated member connected to an installation subject to alternating movements Download PDF

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Publication number
US3788073A
US3788073A US00248727A US3788073DA US3788073A US 3788073 A US3788073 A US 3788073A US 00248727 A US00248727 A US 00248727A US 3788073D A US3788073D A US 3788073DA US 3788073 A US3788073 A US 3788073A
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United States
Prior art keywords
jack
installation
pressure
group
elongated member
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Expired - Lifetime
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US00248727A
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English (en)
Inventor
A Castela
P Joubert
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IFP Energies Nouvelles IFPEN
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IFP Energies Nouvelles IFPEN
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
    • E21B19/08—Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods
    • E21B19/09—Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods specially adapted for drilling underwater formations from a floating support using heave compensators supporting the drill string
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7052—Single-acting output members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7107—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being mechanically linked
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7114—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators
    • F15B2211/7121—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators the chambers being connected in series
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7114—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators
    • F15B2211/7128—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators the chambers being connected in parallel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/76—Control of force or torque of the output member
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S254/00—Implements or apparatus for applying pushing or pulling force
    • Y10S254/90—Cable pulling drum having wave motion responsive actuator for operating drive or rotation retarding means

Definitions

  • ABSTRACT Apparatus for applying a substantially constant tension to an elongated member connected to an installation subjected to alternating movements which comprises the combination of at least one jack supporting said elongated member with regulating means located on the installation, supplying a determined working pressure with the use, as pressure source, of an accumulator delivering to a jack an auxiliary fluid under a pressure varying with the displacement of one element (piston or cylinder) of said jack, comprising at least two jacks, one of which has one element articulated to a fixed point and the other element articulated to one element of another jack through a movable articulation member compelled to be displaced along a predetermined path when one of the elements of a jack is displaced with respect to the other.
  • the present invention relates to an apparatus for applying a substantially constant tension to an elongated member connected to an installation subjected to alternating movements.
  • the invention relates to an apparatus for supporting, with a substantially constant force, an elongated member suspended from an installation subjected to vertical movements.
  • the drill string must be kept under a substantially constant tension, so as to be unaffected by the vertical movements of the floating installation.
  • the upper end of the drill string is generally connected to a hook carried by a travelling block which is suspended, by a cable used for handling the drill string, from a stationary crown block, located at the top of a derrick carried by the floating installation.
  • An automatic compensation for the movements of the floating installation is obtained by supplying the jack with fluid under pressure delivered by an oleopneumatic (oil-and-gas) accumulator.
  • P is the initial gas pressure in the accumulator which is the same as that of the fluid contained in the jack, whereby a tension force can be exerted on the drill string
  • V is the volume of the pressurized gas
  • K a coefficient which depends in particular on the type of gas housed in the accumulator.
  • the volumes V required suppress or at least to reduce the drawbacks of the prior devices by providing a device for keeping a working fluid under substantially constant pressure, this device being, in particular, suitable for use in apparatuses for keeping an elongated member under a substantially constant tension.
  • the apparatus according to the invention for applying a substantially constant tension to an elongated member connected to an installation subjected to alternating movements, comprises in combination a. means for applying a force to the elongated member, including at least one main jack,
  • regulating means on the installation, for supplying a working fluid under a determined pressure, this fluid being supplied to said main jack; this regulating means being interposed between the cylinder of said main jack and a source of at least one pressurized fluid, said source containing a gas whose pressure varies with the volume occupied by the gas, this regulating means comprising at least one group of jacks, an element of at least one jack of said group being connected through a moveable articulation to an element of at least another jack of said group the element of at least one jack of said group which is not connected to said moveable articulation being rotatably mounted on a flxed point of the installation, said moveable articulation being compelled to move along a predetermined path, fixed with respect to the installation, said fixed point being so located that the axis of said rotatable jack remains inclined on said path during the rotation of said rotatable jack, at least one jack of said group being fed with pressurized fluid from said source,
  • One of the advantages of the device according to the invention is to provide an apparatus applying a substantially constant tension to a drill string suspended, through handling means, from the top ofa derrick integral with a mobile installation whose heavy constituting elements are not located at the top of the derrick, so as to improve the stability of the mobile installation.
  • FIG. 1 is an overall view of this apparatus
  • FIGS. 2 and 3 respectively show the variation in the pressure applied to the main jack and in the tension ex; erted on the drill column, as a function of the displacements of the piston of this jack, under the action of the vertical movements of the floating installation.
  • Reference numeral 1 indicates the floating installation topped by a derrick 2.
  • a drill string (not shown) is suspended from the floating installation through handling means constituted, in this particular embodiment, by a hook 3 integral with a travelling block 4 suspended by a cable 5 from a crown block 6.
  • the cable 5, used for handling the drill string passes over a device, which forms no part of the invention, constituted by articulated arms 7 and 8 and pulleys 9 and 10, for preventing wear of the cable which might result from friction on the crown block.
  • the crown block 6 is suspended from the end of the stem of a supporting jack l1 fixed to the derrick 2 and constituting the means for supporting the drill string.
  • This jack is placed substantially in line with the direction of the vertical movements of the floating installation, i.e. along a substantially vertical direction.
  • the jack 1] is connected through a pipe 12 to a regulating device.
  • This device produces a force, in the manner indicated hereinafter, so as to keep under a determined pressure the working fluid supplied to the jack 11.
  • the elements constituting the regulating device have been shown in a vertical position for the clarity of the drawing, but this arrangement is not limitative.
  • the device comprises a first jack 14 having one of its constituting elements for example its cylinder pivotally articulated at one end thereof about a fixed point 15.
  • a point of its second constituting element, for example the point 18 of the stem of the jack, is compelled to move along a determined path 19, so that the axis of the jack 14 has an inclination angle a along the path 19.
  • a pipe 20a connects the jack 14 to an accumulator 20 containing an invariable mass of gas.
  • This accumulator 20 is for example an oleopneumatic accumulator whose pressure varies with the relative displacement of the elements constituting the jack 14 when point 18 moves along the path 19.
  • the path 19 has been so determined that the variations in the inclination a of the jack 14 along the path 19 corresponding to the displacements of the point 18 result in a variation of the ratio of the force exerted by the jack to the component of this force along this path which substantially provides for some compensation of the pressure variations of the fluid in the jack 14.
  • the regulating device is connected to means for converting the component along the path 19 of the force exerted by the jack 14 into a determined pressure P
  • These converting means consist of an intermediate jack 16, whose constituting elements, for example the stem of the jack 16, is connected to the point 18, the other constituting element, for example the cylinder of the jack 16, being integral with a fixed supporting point 17.
  • the cylinder of the jack 16 is articulated about its fixed supporting point 17 and the axis of the jack 16 makes an angle B with the path 19, this angle B varying with the displacements of the point 18 on the path 19.
  • the stem of the jack 16 is subjected to the action of the component along the path 19, of the force exerted by the jack 14, which maintains under a determined pressure the fluid which is contained in the jack l6 and conveyed to the supporting jack 11 through the pipe 12.
  • the pressure P supplied by the jack 16 and the pressure P in the accumulator 20 are interrelated through the relationship P P(S/S) (Cosoz/Cos B)
  • the values of this pressure which correspond to the limit positions (B and H) of the moveable articulation 18 in the guideway 19 (FIG. 1) are respectively n P8 /S) a/ 8) and Pu P (COSa /COS B wherein the indexes B and H indicate the particular values of the different parameters Pu, P, a and B of the relation (1), corresponding to the respective positions B and H of the moveable articulation 18.
  • the values Pu,, and Pu will be selected as a function of the particular conditions of each considered case of utilization.
  • the values of Pu and Pu will for example be determined with consideration of the influence of a system of pulleys interposed between the drill column and the supporting jack 11.
  • Test values are selected for the construction parameters of the regulating system, these parameters being (FIG. 1) the values of d and d (respective distances of the articulation points 15 and 17 from the axis of the guideway 19), the limit values a a and B B,, of the angles a and B and the values of the respective crosssections S and S of the jacks l4 and 16 respectively.
  • the pressure P in this accumulator varies substantially according to a physical law having the form' PV" constant, wherein K is a coefficient whose value depends, in particular, on the nature of the pressurized gas and V is the volume of gas at the pressure P of the accumulator 20, applied to the piston of the jack 14.
  • V and V are the values of the volume of pressurized gas when the position of the moveable articulation 18 is respectively at point B and point H of the guideway 19.
  • V V Letting V V, be defined as AV there results from the relation (5)
  • the value of A V is known, since it is equal to the product of the cross-section S of the jack 14 by the stroke of its piston when the moveable articulation 18 is displaced between points B and H, V being the minimum value of the volume of pressurized gas.
  • each value of h corresponds a well defined position of the moveable articulation 18 along the guideway ilie well defined values for the angles a and B, when the values [3 [3B, dm and S have been fixed.
  • the graphs of FIGS. 2 and 3 show respectively the variations of Pu (expressed in kg/cm and T (expressed in tons), as a function of the stroke h (expressed in meters) of the piston ofjack 11, obtained in accordance with the following data horizontal distance between the axes of pulleys 9 and 10 and the axis of pulley 6 when the latter is in its lowermost position 3.3 meters,
  • the cable 5 forms 12 turns between the pulley 6 and the moveable block or pulley system 4.
  • tension to an elongated member connected to an installation subjected to alternating movements which comprises a combination:

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  • Engineering & Computer Science (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Mining & Mineral Resources (AREA)
  • General Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
US00248727A 1971-05-03 1972-04-28 Apparatus for applying a substantially constant tension to an elongated member connected to an installation subject to alternating movements Expired - Lifetime US3788073A (en)

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Application Number Priority Date Filing Date Title
FR7115911A FR2147771B1 (no) 1971-05-03 1971-05-03

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US00248728A Expired - Lifetime US3788074A (en) 1971-05-03 1972-04-28 Device supplying a working fluid under a determined pressure
US00248727A Expired - Lifetime US3788073A (en) 1971-05-03 1972-04-28 Apparatus for applying a substantially constant tension to an elongated member connected to an installation subject to alternating movements

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US00248728A Expired - Lifetime US3788074A (en) 1971-05-03 1972-04-28 Device supplying a working fluid under a determined pressure

Country Status (13)

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US (2) US3788074A (no)
JP (2) JPS5429961B1 (no)
CA (2) CA957360A (no)
DE (2) DE2221700C3 (no)
DK (2) DK135866B (no)
ES (1) ES402339A1 (no)
FR (1) FR2147771B1 (no)
GB (2) GB1394201A (no)
IT (1) IT954956B (no)
NL (2) NL149253B (no)
NO (2) NO131616C (no)
SE (2) SE393430B (no)
SU (1) SU633496A3 (no)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4213720A (en) * 1977-09-05 1980-07-22 Vickers Limited Tensioning of members
US4739584A (en) * 1986-10-23 1988-04-26 Peter Zellman Garage door locking mechanism
DE3735236A1 (de) * 1987-10-17 1989-04-27 Teves Gmbh Alfred Einrichtung zur anpassung der kennlinie eines hydrospeichers an die kennlinie eines verbrauchers
US4867418A (en) * 1986-03-03 1989-09-19 N.L. Industries, Inc. Apparatus for increasing the load handling capability of support and manipulating equipment
US5160219A (en) * 1991-01-15 1992-11-03 Ltv Energy Products Company Variable spring rate riser tensioner system
US5482406A (en) * 1993-04-15 1996-01-09 Continental Emsco Company Variable spring rate compression element and riser tensioner system using the same
US5520369A (en) * 1984-12-28 1996-05-28 Institut Francais Du Petrole Method and device for withdrawing an element fastened to a mobile installation from the influence of the movements of this installation
US5628586A (en) * 1995-06-23 1997-05-13 Continental Emsco Company Elastomeric riser tensioner system
US5641248A (en) * 1993-04-15 1997-06-24 Continental Emsco Company Variable spring rate compression element and riser tensioner system using the same
US6585455B1 (en) 1992-08-18 2003-07-01 Shell Oil Company Rocker arm marine tensioning system
US20120132435A1 (en) * 2009-07-15 2012-05-31 My Technologies, Llc Downhole Intervention

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3791628A (en) * 1972-07-26 1974-02-12 Ocean Science & Eng Motion compensated crown block system
US3948486A (en) * 1973-09-07 1976-04-06 Institut Francaise Du Petrole, Des Carburants Et Lubrifiants New device for applying a determined force to an element connected to an installation subjected to alternating movements
US3943868A (en) * 1974-06-13 1976-03-16 Global Marine Inc. Heave compensation apparatus for a marine mining vessel
US4688764A (en) * 1984-10-31 1987-08-25 Nl Industries, Inc. Crown block compensator
FR2575452B1 (fr) * 1984-12-28 1987-11-13 Inst Francais Du Petrole Methode et dispositif pour soustraire un element accroche a une installation mobile aux mouvements de cette installation
US5454408A (en) * 1993-08-11 1995-10-03 Thermo Power Corporation Variable-volume storage and dispensing apparatus for compressed natural gas
NO341753B1 (no) * 2013-07-03 2018-01-15 Cameron Int Corp Bevegelseskompensasjonssystem
FR3025787B1 (fr) * 2014-09-16 2019-06-07 IFP Energies Nouvelles Systeme de controle du deplacement d'une charge
FR3060549B1 (fr) * 2016-12-19 2018-12-07 IFP Energies Nouvelles Systeme de compensation de mouvement d'une charge accrochee a une installation mobile avec verin principal et verin secondaire
USD835678S1 (en) * 2017-07-08 2018-12-11 Daqing Dannuo Petroleum Technology Development Co., Ltd. Pumping unit

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163005A (en) * 1962-11-19 1964-12-29 Jersey Prod Res Co Apparatus for use on floating drilling platforms
US3208728A (en) * 1962-11-19 1965-09-28 Exxon Production Research Co Apparatus for use on floating drilling platforms
US3687205A (en) * 1970-10-28 1972-08-29 Gulf Research Development Co Floating rig motion compensator

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163005A (en) * 1962-11-19 1964-12-29 Jersey Prod Res Co Apparatus for use on floating drilling platforms
US3208728A (en) * 1962-11-19 1965-09-28 Exxon Production Research Co Apparatus for use on floating drilling platforms
US3687205A (en) * 1970-10-28 1972-08-29 Gulf Research Development Co Floating rig motion compensator

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4213720A (en) * 1977-09-05 1980-07-22 Vickers Limited Tensioning of members
US5520369A (en) * 1984-12-28 1996-05-28 Institut Francais Du Petrole Method and device for withdrawing an element fastened to a mobile installation from the influence of the movements of this installation
US4867418A (en) * 1986-03-03 1989-09-19 N.L. Industries, Inc. Apparatus for increasing the load handling capability of support and manipulating equipment
US4739584A (en) * 1986-10-23 1988-04-26 Peter Zellman Garage door locking mechanism
DE3735236A1 (de) * 1987-10-17 1989-04-27 Teves Gmbh Alfred Einrichtung zur anpassung der kennlinie eines hydrospeichers an die kennlinie eines verbrauchers
US5160219A (en) * 1991-01-15 1992-11-03 Ltv Energy Products Company Variable spring rate riser tensioner system
US6585455B1 (en) 1992-08-18 2003-07-01 Shell Oil Company Rocker arm marine tensioning system
US5482406A (en) * 1993-04-15 1996-01-09 Continental Emsco Company Variable spring rate compression element and riser tensioner system using the same
US5641248A (en) * 1993-04-15 1997-06-24 Continental Emsco Company Variable spring rate compression element and riser tensioner system using the same
US5628586A (en) * 1995-06-23 1997-05-13 Continental Emsco Company Elastomeric riser tensioner system
US20120132435A1 (en) * 2009-07-15 2012-05-31 My Technologies, Llc Downhole Intervention

Also Published As

Publication number Publication date
DE2221700C3 (de) 1974-04-25
DK135865B (da) 1977-07-04
SE393430B (sv) 1977-05-09
DE2221654A1 (de) 1972-11-30
NL7205930A (no) 1972-11-07
DE2221700A1 (de) 1972-11-16
ES402339A1 (es) 1975-11-01
JPS5429961B1 (no) 1979-09-27
NL149259B (nl) 1976-04-15
DK135866C (no) 1977-12-05
CA956922A (en) 1974-10-29
NO131617B (no) 1975-03-17
SU633496A3 (ru) 1978-11-15
CA957360A (en) 1974-11-05
US3788074A (en) 1974-01-29
DE2221654C3 (no) 1974-04-18
JPS554913B1 (no) 1980-02-01
GB1394202A (en) 1975-05-14
FR2147771B1 (no) 1974-05-31
FR2147771A1 (no) 1973-03-16
NO131616B (no) 1975-03-17
GB1394201A (en) 1975-05-14
DK135865C (no) 1977-11-28
NL149253B (nl) 1976-04-15
DK135866B (da) 1977-07-04
DE2221654B2 (de) 1973-09-06
SE393429B (sv) 1977-05-09
NL7205929A (no) 1972-11-07
IT954956B (it) 1973-09-15
DE2221700B2 (de) 1973-09-27
NO131617C (no) 1975-06-25
NO131616C (no) 1975-06-25

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