NO342817B1 - High pressure depth compensated actuator - Google Patents

High pressure depth compensated actuator

Info

Publication number
NO342817B1
NO342817B1 NO20162010A NO20162010A NO342817B1 NO 342817 B1 NO342817 B1 NO 342817B1 NO 20162010 A NO20162010 A NO 20162010A NO 20162010 A NO20162010 A NO 20162010A NO 342817 B1 NO342817 B1 NO 342817B1
Authority
NO
Norway
Prior art keywords
cylinder
hollow rod
piston
volume
inner diameter
Prior art date
Application number
NO20162010A
Other languages
Norwegian (no)
Other versions
NO20162010A1 (en
Inventor
Tord Martinsen
Original Assignee
Safelink As
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Safelink As filed Critical Safelink As
Priority to NO20162010A priority Critical patent/NO342817B1/en
Priority to SG11201808851PA priority patent/SG11201808851PA/en
Priority to SG10201913233VA priority patent/SG10201913233VA/en
Priority to CN201780028271.XA priority patent/CN109477361B/en
Priority to MX2018013619A priority patent/MX2018013619A/en
Priority to MYPI2018703631A priority patent/MY196914A/en
Priority to AU2017262380A priority patent/AU2017262380B2/en
Priority to EP17796464.0A priority patent/EP3455449A4/en
Priority to US16/099,634 priority patent/US10975632B2/en
Priority to PCT/NO2017/050111 priority patent/WO2017196181A1/en
Priority to CA3018541A priority patent/CA3018541A1/en
Priority to BR112018072874-8A priority patent/BR112018072874B1/en
Publication of NO20162010A1 publication Critical patent/NO20162010A1/en
Publication of NO342817B1 publication Critical patent/NO342817B1/en

Links

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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423—Component parts; Constructional details
    • F15B15/1466—Hollow piston sliding over a stationary rod inside the cylinder
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1409—Characterised by the construction of the motor unit of the straight-cylinder type with two or more independently movable working pistons
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/24—Other details, e.g. assembly with regulating devices for restricting the stroke
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/006—Compensation or avoidance of ambient pressure variation
    • 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
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
    • F16K31/122—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston
    • F16K31/1225—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston with a plurality of pistons

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Actuator (AREA)

Abstract

High pressure depth compensated actuator (100) for use in subsea conditions comprising: - a hollow rod actuator (10), consisting of a first cylinder(11), a first piston(12), a first hollow rod (13), connection means(16) at each axial end of the hollow rod actuator (10), a second cylinder (14) mounted concentric with the first cylinder(11) and fastened to the upperend of the first cylinder (11) and a second piston(15) mounted at the lowerend of these condcylinder(14); -a first volum e (V1) is formed by the outer diameter of the hollow rod (13), the lowerend of the first cylinder(11), the inner diameter of the first cylinder(11) and the lowerend of the first piston (12), and may be filled with oil, gas or be under vacuum; - a second volume (V2) is formed by the outer diameter of the second cylinder (14), the upperend of the first cylinder (11), the inner diameter of the first cylinder (11), the upperend of the first piston (12), the inner diameter of the first hollow rod (13) and the upperend of the second piston (15) and may be filled with oil, gas or be under vacuum; -a third volume(V3) is formed by the inner diameter of the second cylinder (14), the upperend of the first cylinder (11), the inner diameter of the hollow rod (13), the lowerend of the second piston (15) and the lower end of the hollow rod (13), and may be filled with oil, gas or be under vacuum; -a depth compensator (20), consisting of a third cylinder (21), a second hollow rod (22), a fourth cylinder (23) mounted concentric with the third cylinder(21) and fastened to the upperend of the third cylinder(21), a third piston (24) mounted at the lower end of the fourth cylinder and a mechanical stroke limiter (25) mounted at the upperend of the second hollow rod (22), preventing the second hollow rod (22)from stroking excessively;-a fourth volume (V4) volume is formed between the lower end of the third cylinder (21), the inner diameter of the third cylinder (21), the outer diameter of the fourth cylinder (23), upperend of the third piston (24) and displaced by the second hollow rod (22) as well as the mechanical stroke limiter (25), which may be filled with gas or be under vacuum; -a fifth volume(VS) is formed between the lower end of the second hollow rod (22), the inner diameter of the fourth cylinder (23), the lower end of the second hollow rod (22), the upper end of the third cylinder (23) and the lower end of the third piston (24), which may be filled with oil; conduit means(17) between the fifth volume (V5) and the third volume (V3).High pressure depth compensated actuator (100) for use in subsea conditions comprising: - a hollow rod actuator (10), consisting of a first cylinder (11), a first piston (12), a first hollow rod (13), connection means (16) at each axial end of the hollow rod actuator (10), a second cylinder (14) mounted concentric with the first cylinder (11) and fastened to the upper end of the first cylinder (11) and a second piston (15) mounted on the lower end of these condenser (14); -a first volume e (V1) is formed by the outer diameter of the hollow rod (13), the lower end of the first cylinder (11), the inner diameter of the first cylinder (11) and the lower end of the first piston ( 12), and may be filled with oil, gas or under vacuum; - a second volume (V2) is formed by the outer diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the first cylinder (11), the upper end of the first piston (12) ), the inner diameter of the first hollow rod (13) and the upper end of the second piston (15) and may be filled with oil, gas or under vacuum; -a third volume (V3) is formed by the inner diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the hollow rod (13), the lower end of the second piston (15) ) and the lower end of the hollow rod (13), and may be filled with oil, gas or under vacuum; -a depth compensator (20), consisting of a third cylinder (21), a second hollow rod (22), a fourth cylinder (23) mounted concentric with the third cylinder (21) and fastened to the upper end of the third cylinder (21) 21), a third piston (24) mounted at the lower end of the fourth cylinder and a mechanical stroke limiter (25) mounted at the upper end of the second hollow rod (22), preventing the second hollow rod (22) from stroking excessively ; -a fourth volume (V4) volume is formed between the lower end of the third cylinder (21), the inner diameter of the third cylinder (21), the outer diameter of the fourth cylinder (23), the upper end of the third piston (24) and displaced by the second hollow rod (22) as well as the mechanical stroke limiter (25), which may be filled with gas or under vacuum; -a fifth volume (VS) is formed between the lower end of the second hollow rod (22), the inner diameter of the fourth cylinder (23), the lower end of the second hollow rod (22), the upper end of the third cylinder (23) and the lower end of the third piston (24), which may be filled with oil; conduit means (17) between the fifth volume (V5) and the third volume (V3).

Description

The high pressure depth compensated actuator (HPDCA) is an actuator design intended for subsea usage. It compensates for water pressure effects that often are problematic.
BACKGROUND OF THE INVENTION
Prior art depth compensated actuators (e.g. US 2008/0251980 A1) do exist. The main difference between the prior art and the invention is how the depth compensation is performed. The prior art compensation is performed utilizing an external cylinder to compensate the effect of the water pressure acting on the piston rod. This requires at least one large second hydraulic cylinder connected to the main hydraulic cylinder. The main disadvantages of the prior art are that the depth compensator is heavier than required and it has more friction than required. Prior art also lacks a surface in the actuator to be used in combination with active pressure control (i.e. active heave compensation).
The reason why the prior art is heavier than needed is that the entire volume of the actuator has to filled with oil and that same oil has to be able to fit within the depth compensator cylinder. The HPDCA uses a hollow rod actuator to significantly reduce the required size and weight of the depth compensator as only the volume of the inner tube has to be filled with oil. Friction is also much smaller as the seal size is significantly reduced (from full actuator diameter to rod inner diameter).
DE 102014215313 A1 describes another prior art heave compensator device with an actuator with oil filled chamber beneath piston and gas filled chamber in connection via a valve with gas tanks above piston where oil filled chamber in connected via a valve to oil filled chamber in oil over gas depth compensator where valves are controlled by remote control.
WO 2016/122321 A1 further describes a prior art of a compensator device including a hydraulic cylinder with a hollow inner cylinder rod having an end with a blocking diameter and having a cavity to receive the blocking diameter of the inner cylinder rod allowing the compensator for higher force on the inner cylinder rod as the blocking diameter and thus the blocking area is larger than the compensation pressure area.
US 2015/0354604 A1 describes a hydraulic adjusting device for use in a power plant and/or a wind power plant and includes a double-acting adjusting cylinder pressurized with a working pressure medium further connected to a reservoir with a pressurized gas.
SUMMARY OF THE INVENTION
The main features of the present invention are given in the independent claim. Additional features of the invention are given in the dependent claims.
The novel design of the HPDCA is use of a hollow rod actuator combined with a high pressure depth compensator cylinder, to provide a light design with a minimum amount of friction while adding an extra pressure surface.
BRIEF DESCRIPTION OF THE DRAWINGS
Figures 1 is a schematic illustration of the HPDCA according to the present invention in which the major component parts of the HPDCA are specifically identified.
Figure 2 is an illustration of a prior art depth compensated actuator.
DETAILED DESCRIPTION
As previously mentioned, figure 1 illustrates the HPDCA (0) with all of the major sub-components numbered 1 through 25, as well as all volumes indicated by V1 through V5. In Table 1, the component description is identified. The hydraulically depth compensated actuator (HPDCA) (0) can be used vertically, horizontally or at an angle. One application can be as an actuator for subsea valves operated at low pressure; another is as an actuator used at different water depths, typically as part of a heave compensator.
Figure 1 shows the invention, details explained below:
- a hollow rod actuator (10), consisting of a first cylinder (11), a first piston (12), a first hollow rod (13), connection means (16) at each axial end of the hollow rod actuator (10), a second cylinder (14) mounted concentric with the first cylinder (11) and fastened to the upper end of the first cylinder (11) and a second piston (15) mounted at the lower end of the second cylinder (14)
- a first volume (V1) is formed by the outer diameter of the hollow rod (13), the lower end of the first cylinder (11), the inner diameter of the first cylinder (11) and the lower end of the first piston (12), and may be filled with oil, gas or be under vacuum
- a second volume (V2) is formed by the outer diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the first cylinder (11), the upper end of the first piston (12), the inner diameter of the first hollow rod (13) and the upper end of the second piston (15) and may be filled with oil, gas or be under vacuum
- a third volume (V3) is formed by the inner diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the hollow rod (13), the lower end of the second piston (15) and the lower end of the hollow rod (13), and may be filled with oil, gas or be under vacuum
- a depth compensator (20), consisting of a third cylinder (21), a second hollow rod (22), a fourth cylinder (23) mounted concentric with the third cylinder (21) and fastened to the upper end of the third cylinder (21), a third piston (24) mounted at the lower end of the fourth cylinder and a mechanical stroke limiter (25) mounted at the upper end of the second hollow rod (22), preventing the second hollow rod (22) from stroking too much
- a fourth volume (V4) volume is formed between the lower end of the third cylinder (21), the inner diameter of the third cylinder (21), the outer diameter of the fourth cylinder (23), upper end of the third piston (24) and displaced by the second hollow rod (22) as well as the mechanical stroke limiter (25), which may be filled with gas or be under vacuum
- a fifth volume (V5) is formed between the lower end of the second hollow rod (22), the inner diameter of the fourth cylinder (23), the lower end of the second hollow rod (22), the upper end of the third cylinder (23) and the lower end of the third piston (24), which may be filled with oil
- conduit means (17) between the fifth volume (V5) and the third volume (V3)
The invention shown in figure 1 works in the following way:
- Both hollow rods are exposed to external pressure.
- The third volume and the fifth volume is connected through a conduit and will have the same pressure (internal pressure).
- To negate external pressure influence on the first hollow rod, the internal pressure needs to be equal to the external pressure times the square of the ratio between the outer and inner
diameter of the first hollow rod A force balance gives:
- A second requirement is that the volume of the fifth volume is large enough to provide oil to the third volume for the entire usable stroke length.
- To achieve these requirements, the diameter ratio between the outer and inner diameter of the second hollow rod needs to be the same as the ratio between the outer and inner
diameter of the first hollow rod a second requirement is then that the inner
diameter of the second hollow rod needs to be equal to the inner diameter of the first hollow rod times the square root of the ratio of the stroke length of the first hollow rod and the stroke
length of the second hollow rod
- The first volume (V1) can be used for passive heave compensation means by connecting it to a gas accumulator.
- The second volume is left unused and can be utilized as an extra pressure surface for active heave compensation purposes by connecting it to e.g. a pump.
- The fourth volume should normally be without pressure.
Table 1

Claims (1)

1. High pressure depth compensated actuator (100) for use in subsea conditions characterised by:
a hollow rod actuator (10), consisting of a first cylinder (11), a first piston (12), a first hollow rod (13), connection means (16) at each axial end of the hollow rod actuator (10), a second cylinder (14) mounted concentric with the first cylinder (11) and concentric within the first hollow rod (13) and fastened to the upper end of the first cylinder (11) and a second piston (15) mounted at the lower end of the second cylinder (14);
a first volume (V1) is formed by the outer diameter of the hollow rod (13), the lower end of the first cylinder (11), the inner diameter of the first cylinder (11) and the lower end of the first piston (12), and is filled with oil, gas or is under vacuum;
a second volume (V2) is formed by the outer diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the first cylinder (11), the upper end of the first piston (12), the inner diameter of the first hollow rod (13) and the upper end of the second piston (15) and is filled with oil, gas or is under vacuum;
a third volume (V3) is formed by the inner diameter of the second cylinder (14), the upper end of the first cylinder (11), the inner diameter of the hollow rod (13), the lower end of the second piston (15) and the lower end of the hollow rod (13), and is filled with oil;
a depth compensator (20), consisting of a third cylinder (21), a second hollow rod (22) which is exposed to external pressure at its lower end, a fourth cylinder (23) mounted concentric with the third cylinder (21) and concentric within the second hollow rod (22) and fastened to the upper end of the third cylinder (21), a third piston (24) mounted at the lower end of the fourth cylinder (23) and a mechanical stroke limiter (25) mounted at the upper end of the second hollow rod (22), preventing the second hollow rod (22) from stroking excessively out of the third cylinder (21);
a fourth volume (V4) is formed between the lower end of the third cylinder (21), the inner diameter of the third cylinder (21), the outer diameter of the fourth cylinder (23), upper end of the third piston (24) and displaced by the second hollow rod (22) as well as the mechanical stroke limiter (25), which is filled with gas or is under vacuum;
a fifth volume (V5) is formed between the lower end of the second hollow rod (22), the inner diameter of the fourth cylinder (23), the inner diameter of the second hollow rod (22), the upper end of the third cylinder (23) and the lower end of the third piston (24), which is filled with oil;
conduit means (17) between the fifth volume (V5) and the third volume (V3).
NO20162010A 2016-05-08 2016-12-17 High pressure depth compensated actuator NO342817B1 (en)

Priority Applications (12)

Application Number Priority Date Filing Date Title
NO20162010A NO342817B1 (en) 2016-12-17 2016-12-17 High pressure depth compensated actuator
SG11201808851PA SG11201808851PA (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
SG10201913233VA SG10201913233VA (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
CN201780028271.XA CN109477361B (en) 2016-05-08 2017-05-08 Depth compensation actuator and use thereof in connection with a movable heave compensator
MX2018013619A MX2018013619A (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator.
MYPI2018703631A MY196914A (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a tranportable heave compensator
AU2017262380A AU2017262380B2 (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
EP17796464.0A EP3455449A4 (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
US16/099,634 US10975632B2 (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
PCT/NO2017/050111 WO2017196181A1 (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
CA3018541A CA3018541A1 (en) 2016-05-08 2017-05-08 Depth compensated actuator and use of same in association with a transportable heave compensator
BR112018072874-8A BR112018072874B1 (en) 2016-05-08 2017-05-08 DEPTH COMPENSATED HYDRAULIC ACTUATOR

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NO20162010A NO342817B1 (en) 2016-12-17 2016-12-17 High pressure depth compensated actuator

Publications (2)

Publication Number Publication Date
NO20162010A1 NO20162010A1 (en) 2018-06-18
NO342817B1 true NO342817B1 (en) 2018-08-13

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
NO20162010A NO342817B1 (en) 2016-05-08 2016-12-17 High pressure depth compensated actuator

Country Status (1)

Country Link
NO (1) NO342817B1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080251980A1 (en) * 2007-04-10 2008-10-16 Matthew Jake Ormond Depth compensated subsea passive heave compensator
US20150354604A1 (en) * 2012-06-20 2015-12-10 Robert Bosch Gmbh Hydraulic Adjusting Device
DE102014215313A1 (en) * 2014-08-04 2016-02-04 Robert Bosch Gmbh Seegangskompensationseinrichtung
WO2016122321A1 (en) * 2015-01-29 2016-08-04 Ihc Holland Ie B.V. Compensator device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080251980A1 (en) * 2007-04-10 2008-10-16 Matthew Jake Ormond Depth compensated subsea passive heave compensator
US20150354604A1 (en) * 2012-06-20 2015-12-10 Robert Bosch Gmbh Hydraulic Adjusting Device
DE102014215313A1 (en) * 2014-08-04 2016-02-04 Robert Bosch Gmbh Seegangskompensationseinrichtung
WO2016122321A1 (en) * 2015-01-29 2016-08-04 Ihc Holland Ie B.V. Compensator device

Also Published As

Publication number Publication date
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Owner name: SAFELINK AHC AS, NO