Classifications

• • 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
  • E21B7/00—Special methods or apparatus for drilling
  • E21B7/18—Drilling by liquid or gas jets, with or without entrained pellets
• • 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
  • F15B3/00—Intensifiers or fluid-pressure converters, e.g. pressure exchangers; Conveying pressure from one fluid system to another, without contact between the fluids

Definitions

• This invention relates to an improved design of a pressure amplifier or pressure converter for mounting above the drill bit at the lower end of a drill pipe for deep drilling, in particular for oil and gas, and for generating an increased fluid pressure by utilizing energy in a drilling fluid flow downwards through the drill string and the drill pipe. This can be done for the purpose of obtaining an enhanced drilling effect, preferably by means of one or more high pressure jets adapted to have a cutting effect in a surrounding rock formation.
• the invention can be considered as a further development and improvement of structures described in Norwegian patent specifications Nos. 169.088, 171.322, 171.323 and 171.325. It has now been found that these and other known pressure converters advantageously can be replaced by or modified into new and improved designs to be described in the following description. These new designs involve among other things, an increased yield with respect to delivered amount of drillng fluid at increased pressure.
• the present invention as a starting point takes an embodiment comprising a reciprocating piston which is moveable under the influence of drilling fluid pressure, between opposite end positions in a cylinder.
• the piston has a relatively large piston area which during piston movement in a first direction is influenced by the drilling fluid pressure in the drill pipe, and an oppositely facing, relatively small piston area, which during piston movement in the first direction generates an increased pressure in a smaller portion of the drilling fluid flow.
• Valve means control the drilling fluid flow to and from the cylinder with the piston, through conduits which communicate with drilling fluid flow passages within the drill pipe and the annulus outside the drill pipe, where the drilling fluid has a relatively low pressure.
• a high pressure conduit with a check valve connects the space in front of the small piston area to a header conduit for drilling fluid at the increased pressure.
• the piston is provided with another relatively large piston area facing oppositely in relation to the first mentioned large piston area and adapted to be influenced by the drilling fluid pressure in the drill pipe for moving the piston in another, opposite direction of said first direction, that there ⁇ s further provided a second, relatively small piston area facing oppositely in relation to the first mentioned small pistion area and being during piston movement in the other, opposite direction, adapted to generate an increased drilling fluid pressure, and that a second high pressure conduit with a second check valve serves to connect the space in front of the second, opposite small piston area, to the header conduit.
• Fig. l in longitudinal section shows a first embodiment of a pressure converter according to the invention, with the piston in an upper end position
• Fig. 2 shows a cross-section along the lines II-II in
• Fig. 1, and Fig. 3 in longitudinal section shows another embodiment of the pressure converter according to the invention, with the piston in an upper end position. Since the present pressure converter as far as the main features thereof are concerned, is closely related to corresponding structures according to the Norwegian patent specifications referred to above, it seems sufficient here only briefly to discuss these main features and functions.
• Fig. l comprises as substantially cylindrical housing 1, 2, 3 adapted to enclose a piston 6.
• This has several active piston areas, i.e. in the first place an upper relatively large piston area 11, a second large piston area 13 and an opposite, relatively small piston area 12 at the lower end of piston member 6.
• This is adapted to be freely oveable axially under the influence of varying drilling fluid pressures at the respective piston areas.
• the space or volume in front of piston area 11 can be designated low pressure space, whereas the volume in front of piston area 12 correspondingly can be designated high pressure space.
• This latter space is connected through a conduit 15 with a check valve 15A, to a header conduit 16 for the resulting drilling fluid flow at an increased pressure.
• Conduit 16 runs through the whole longitudinal direction of the housing, i.e. the cylinder wall 1, for the purpose of interconnecting several of these pressure converter unit to a group.
• the embodiment of Fig. 1 has an extension upwards ending at a second, relatively small piston area 14 which is facing oppositely in relation to said first small piston area 12.
• a second high pressure conduit 25 with an associated check valve 25A leading forward to the header conduit 16 mentioned above.
• the pressure converter will have a working stroke both upwardly and downwardly, so that a return stroke without an actual pressure increasing effect as in the previously known designs referred to above, does not occur. Hence this involves a substantially enhanced yield.
• valve means adapted to be influenced by the large piston areas 11 and 13 at the respective end positions of the piston.
• This valve means comprise two auxiliary slides 24A and 24B being displaceable in associated bores in parallel to the cylinder axis.
• the auxiliary slide 24A is pushed upwards by piston area 11.
• the auxiliary slide 24B then is located in an upper position resulting from spring loading, and has its end portion 26B projecting a small distance into the space in front of piston area 13.
• drilling fluid under pressure from an inlet 32 via auxiliary slide 24A is directed to the end of a main valve with slide 4, which is thereby pushed to a lower position, and opens for drilling fluid through the inlet opening 32, som that the pressure from this inlet acts against piston area 11. Then a downward piston movement can be initiated, since the space at the underside of the piston has now through the main valve been connected to an outlet 34 to the annulus 50.
• FIG. 2 shows the drill pipe 10 and the cylinder member 2 which has recesses so as to form flow passages 1A, IB, IC and ID for the drilling fluid flow through the drill pipe past the whole cylinder l, 2, 3.
• Fig. 2 shows the bore 4A for the main valve or slide 4 as shown in Fig. 1.
• corresponding bores 4B, 4C and 4D for a total of four main valves which all operate synchronized and can be controlled by the same two auxiliary slides 24A and 24B, or there can be provided individual auxiliary slides or auxiliary valves for each of the main valves 4A, 4B, 4C and 4D.
• Corresponding openings can also be provided for one or more of the other main valves.
• valve arrangement according to the embodiment of Figs. 1 and 2 employ drilling fluid pressure for repositioning the main valve
• the valve arrangement according to the embodiment of Fig. 3 is based on direct mechanical action from piston 6 for moving a main valve slide 44 having quite corresponding functions as slide 4 in Fig. 1.
• the main slide 44 has an extension with a transverse member 45 which in turn has an extension part 46 adapted to project into the space in front of piston area 13 in the upper position of slide 44.
• This positon of the valve arrangement is provided for by the upper, large piston area 11 on piston 6, which in Fig. 3 has pushed up an extension 48 which through a transverse member 47 is connected to the upper end of slide 44.
• FIG. 3 there are shown pressure inlets 33 and 36 as well as return ports or outlets 30 and 34, corresponding to those shown in Fig. 1.
• Inlet 35 supplies drilling fluid to the high pressure side or cylinder in front of piston area 12.
• each such main slide advantageously is spring loaded in a corresponding manner as the main valve slide 4 in Fig. 1, in such a sense that appropriate starting from stand-still will be secured.
• the effective design length of each pressure converter unit is much shorter than in previously known designs having the same capacity. This apparently is very important when several pressure converter units shall be assembled into a group, which is common in practice.
• the embodiment of Fig. 3 is preferred for the one in Fig. l, in so far as the valve mechanism in Fig. 3 is simpler and operates more directly.

Landscapes

• Engineering & Computer Science (AREA)
• Mining & Mineral Resources (AREA)
• Life Sciences & Earth Sciences (AREA)
• Geology (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Environmental & Geological Engineering (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Earth Drilling (AREA)
• Drilling And Boring (AREA)
• Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
• Supply Devices, Intensifiers, Converters, And Telemotors (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19898079

Family Applications (1)

Country Status (8)

Cited By (2)

Families Citing this family (7)

Citations (4)

Family Cites Families (2)

• 1995
  • 1995-03-31 NO NO951272A patent/NO300232B1/no unknown
• 1996
  • 1996-03-05 KR KR1019970706819A patent/KR19980703415A/ko not_active Application Discontinuation
  • 1996-03-05 BR BR9607910A patent/BR9607910A/pt not_active Application Discontinuation
  • 1996-03-05 US US08/913,992 patent/US5984026A/en not_active Expired - Fee Related
  • 1996-03-05 CA CA002216556A patent/CA2216556A1/en not_active Abandoned
  • 1996-03-05 AU AU52903/96A patent/AU694860B2/en not_active Ceased
  • 1996-03-05 WO PCT/NO1996/000050 patent/WO1996030618A1/en not_active Application Discontinuation
  • 1996-03-05 EP EP96909393A patent/EP0815338A1/en not_active Withdrawn
• 1997
  • 1997-09-24 NO NO974428A patent/NO974428D0/no not_active Application Discontinuation

Patent Citations (4)

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