CA1316702C - Apparatus for the generation of pressure pulses in drilling mud compositions - Google Patents

Apparatus for the generation of pressure pulses in drilling mud compositions

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Publication number
CA1316702C
CA1316702C CA000566212A CA566212A CA1316702C CA 1316702 C CA1316702 C CA 1316702C CA 000566212 A CA000566212 A CA 000566212A CA 566212 A CA566212 A CA 566212A CA 1316702 C CA1316702 C CA 1316702C
Authority
CA
Canada
Prior art keywords
valve
interior
primary valve
exterior
valve member
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
CA000566212A
Other languages
French (fr)
Inventor
Dagobert Feld
Johann Biehl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baker Hughes Oilfield Operations LLC
Original Assignee
Eastman Christensen Co
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 Eastman Christensen Co filed Critical Eastman Christensen Co
Application granted granted Critical
Publication of CA1316702C publication Critical patent/CA1316702C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00Survey of boreholes or wells
    • E21B47/12Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
    • E21B47/14Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves
    • E21B47/18Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves through the well fluid, e.g. mud pressure pulse telemetry

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Geology (AREA)
  • Remote Sensing (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Geophysics (AREA)
  • Acoustics & Sound (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Lift Valve (AREA)

Abstract

ABSTRACT OF THE INVENTION

The apparatus for the generation of pressure pulses in a drilling mud composition which flows downward in a drill string (1) is composed of a valve (V) inside the drill string (1), with a stationary, braced, pipe-shaped exterior part (3), pipe-shaped primary valve (4) which can be translated from a lower starting position against the flow direction (2) of the drilling mud composition into an upper operational end position, a stationary, pipe-shaped support (5) in a coaxial position inside primary valve (4), an auxiliary valve (13) and (14) actuated by motor means (15). Exterior part (30) and primary valve (4) delimit a constricted segment (29) whose flow cross section can be modified by the position of primary valve (4), and primary valve (4) and the support (5) surround an interior flow channel (21), (12) and (10), and outlet orifice (13) of auxiliary valve (14) can be opened and closed. The sum of the downward hydraulic forces and the gravitational forces in the drilling mud composition acting on the primary valve in its starting position when auxiliary valve (13) and (14) is open exceeds the upward hydraulic forces, and these force relations can be reversed by closing auxiliary valve (13) and (14). In the operational end position of primary valve (4), the sum of all forces acting on primary valve (4) is equal to zero, and primary valve (4) is suspended without contact in the drilling mud composition (Figure 4).

EASD:032/C4

Description

13~ ~r~2 BACKGROUND OF THE INVENTION

The invention relates to an apparatus for the generation of pressure pulses in a drilling mud composition which flows downward in a drill string.

According to a known apparatus of this type (U.S.
Patent No. 3,958,217), the exterior part of the valve forms a valve seat, which limits the upward motion of the primary valve in the final operational position acting as a restrictor, and which, with engagement of the primary valve, blocks the central flow passage for the drilling mud composition. The support acting as a restrictor determines the final position of the primary valve. The sum of the downward hydraulic forces which are exerted on the primary valve in its starting position, when the auxiliary valve for the drilling mud composition is open, exceeds the sum of the upward hydraulic forces, with the result that the primary valve is immobilized in its starting position when the auxiliary valve is open. When the auxiliary valve is closed, the pressure relation is reversed, resulting in the upward motion of the primary valve until it reaches its final position as determined by the valve seat.
SUMMARY OF THE INVENTIQN

The invention is based on the problem of creating an apparatus of the type described above, which has a valve with simple construction design, which operates without percussive effects, avoids mechanical abrasion and remains perfectly operational even after a longer operation period without maintenance.

In a preferred embodiment of an apparatus according to the invention, the primary valve reaches a final 13~6~J'~2 operational position solely as a result of an equilibrium of ~orces acting on it, thus avoiding percussive efects resulting from the impact of the primary valve with a stop which defines the final operational position in the pressure pulse generation, and without a restrictor to achieve the final operational position~ When percussive effects are avoided, abrasion and damage are avoided at the same time, and this to a larger extent the higher the upward velocity at the time of the impact of the primary valve with the restrictor. Since, with the exception of the forces of gravity, the fir.al operational position of the primary valve is exclusively due to the hydraulic force of the drilling mud composition acting on primary valve, it is possible to select for the primary valve, whose configuration determines the upward motion of the primary valve, an acceleration pathway with respect to the rate of change of velocity over the pulse height which does not require any of the precautions which have to be considered if the final operational position is predetermined by a restrictor because this causes an abrupt braking of the primary valve due to collision. It is possible to implement the apparatus according to a very simple construction design which allows proper functioning even after prolonged use without maintenance.
BRIEF DESCRIPTION OF T~E DRAWINGS

Further details and advantages are contained in the description and the drawings which illustrate schematically one execution example of the object of the invention. The drawings consist of:

Figure 1, a simplified partial cross section of a drill string in the drill hole of a deep drill hole;

1 3 ~ 2 Figure 2, a partial cross section of a pressure pulse generating apparatus according to the invention in a drill string according to Figure 1, with the main body valve in the starting position, Figure 3, a representation corresponding to Figure 2 with the primary valve in the final operational position;
and Figure 4, a cross section similar to Figures 2 and 3 with the primary valve in the upper position after the movement.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The apparatus generates pressure pulses in a drilling mud composition which moves downward in the direction of arrow (2) in a drill string and which flows upward, after flowing through a bit (D) at the tip of drill string (1) into the drill hole (B), in the ring space (S) between its wall and the exterior wall of the drill string. The apparatus consists essentially of a valve ~V) positioned in drill string (1), which valve consists of an external part (3), a primary valve (4) and a support (5).
The apparatus for the generation of pressure pulses is part of an apparatus for the determination and teletransmission of data (E), or it operates in conjunction wîth su~h an apparatus, which is also positioned in drill string (1), in general, immediately below valve (V).

The pressure pulses, which are generated by pump ~P) in the drilling mud composition which is pumped downward, are received by pressure sensor (R) and are transmitted 1 3 ~
from the sensor to processing unit (T), in which the signals received are evaluated.

The stationary, essentially pipe-shaped exterior section (3), is braced in drill string (1) and consists of an upper ring section (6) with a central axial flow orifice (7), whose cross section is significantly less than the free cross section of drill string (1) above valve (V). Furthermore, stationary exterior section (3) is braced by bottom (8) of support (5) in its lower section, which has a closed construction in its central section (9), with the exception of an axial flow orifice (10). However, between area (9) and the internal side of exterior section (3) there remain drilling mud composition flow orifices (11'), distributed over the circumference, with a downward flow of drilling mud through a ring-shaped exterior flow channel (11) between exterior section (3) and primary valve (4).

80ttom (8) is either a separate part or an integral part of support (5), whose construction is essentially pipe-shaped with a central flow orifice (12) in its upper section, which is connected to the flow orifice (10) of bottom (9). A valve seat (13) in the lower section of this flow orifice serves simultaneously as the outlet orifice of an interior flow channel, which is delimitated at its lower section by axial flow orifices (12) and (10).

The valve seat with respect to outlet orifice (13) is associated with an auxiliary valve body (14), which may be moved by a motor means, indicated schematically at (15), for example, an electromagnet, from the open position shown in Figure 2 to the closed position shown in Figure 3, so that it closes outlet orifice (13).

~ 3 ~
The construction of support (5) in the area of exterior surface (16) of its upper section (17) is essentially cylindrical, and it forms with this exterior surface (16) an internal ring-shaped slit (18), which on its exterior is limited by an essentially cylindrical interior surface (19) of pipe-shaped contact piece (20) of primary valve (4). The starting position of primary valve (4) shown in Figure 2 with the entire length of opposite surfaces (16) and (19) defines an area of overlap between primary valve (4) and support (5), whose length decreases as soon as primary valve (4) is set in upward motion.

The cylindrical (or annular) slit (18) between primary valve (4) and support (5) gives free access to the drilling mud composition which flows as a result of a pressure gradient between the drilling mud in flow orifice (12) and in exterior flow channel (11). Thus, slit (18) can form, either over the whole length, or, as represented, in consecutively arranged partial sections (18'), a small-diameter constricted path in which the slit width is less than one-hundredth of the diameter of the ring-shaped slit (18), preferably in the range of 0.05-0.5 mm, more preferably 0.15 mm.

The upper front section (22) of primary valve (4) is closed with the exception of flow orifice (21~, and in the illustrated example it has a conical transition area (23) on its exterior. The middle section of the front section is transformed into a pipe-shaped section (24). Lateral flow orifices (25) in this section (24) communicate with flow orifice (21). Section (24) is closed at front section (26), and in the starting position of the primary valve (Figure 2) it is in a position in which the lower edge (27) of lateral orifices (25~ is located in cylindrical flow orifice (7) in ring section (6) of exterior part (3). These lateral orifices [25) form the 133L~irl~

inlet orifices for the interior flow channel whose upper section is surrounded by flow orifice (21) and which is continued by the flow orifices (10) and (12). Section (24) forms a kind of Pitot tube with an essentially S constant diameter over its entire length.

In flow area (23) of primary valve (4) the diameter increases regularly as the separation distance from upper end (26) of primary valve (4) increases to diameter (dl), which in the illustrated example has approximately the same magnitude as diameter (d2) of axial flow orifice (7) which forms a cylindrical constriction. Furthermore, diameter (dl) is essentially equal to diameter (d3) of surface (19) of part (20) of primary valve (4). Further details concerning the diameter and its determination respectively are provided below.

Ring body (6) of exterior part (3) also has a transition area (28) whose diameter increases regularly as the axial separation from the upper end of exterior section (3) increases. In the illustrated example it takes the form of a conical widening.

Instead of the represented increase of diameters of transition areas (23) and (28) which is linear with respect to each respective separation distance, it is also possible to configure the regular increase in diameter with increasing separation distance so that transition areas (23) and (28) exhibit concave or convex curvatures or arc-shaped curvature surfaces.

Exterior section (3) and primary valve (4) in combination form a constricted segment (29) in the upper section of exterior flow channel (11), whose flow cross section can be changed as a function of the position of primary valve (4). This constricted segment (29) is set ~ 3 ~
on the basis of the initial and operation position of primary valve (4) some distance above transition area (28) of exterior part (3), and it ends some distance below transition area (23) of primary valve (4). In the S illustrated example, the flow cross section of constricted segment (29) (between transition areas (23) and (28)), exhibits in the valve area an overall flow cross section increase in the downstream direction. This is implemented by the fact that the diameter of transition area (28) of exterior part (3) increases more than the diameter of transition area (23), which can also be achieved with arc-shaped curvature surfaces in transition areas (23) and (28).

The surface of primary valve (4) is equipped in the area of constricted segment (29) with a wear-resistant shield (30), preferably consisting of a solid tungsten carbide coating.

In the starting position (Figure 2), primary valve (4) can rest with its lower front end (31) on a shoulder (32) of support (5), however, a ring-shaped separation piece (33) can be provided to modify the starting position which is located between lower front end (31) of primary valve (4) and shoulder (32) of support (5). With the help of such separation pieces, primary valve (4) can be shifted toward the top to compensate for changed flow conditions in the drilling mud composition brought about by reduced volume flow per time unit.
Primary valve (4) is fitted with a schematically illustrated restrictor (34), which provides the latter with an end-of-motion position (Figure 4) above the operational position (Figure 3), in which a residual flow passage for the drilling mud composition remains between primary valve (4) and exterior (3). However, primary 13~L~r~2 valve (4) reaches this starting position only if drill string (1) is lowered into drill hole (B), for example, in the round trip, when there is drilling mud composition present in drill hole (B) flowing upward in an exterior S flow channel (21), (12) and (10) of valve (V~ and tending to pull primary valve (4) upward. This restrictor (34) can be omitted if ring section part (6) contains a bypass orifice, indicated by a dotted line at 35.

To generate a pressure pulse in the drilling mud composition a regulated device (E) closes auxiliary valve (13) and (143 and thus stops the flow through interior flow channel (21), (12) and (10). The drilling mud pressure which builds in interior flow channel (21), (12) and (10) is essentially identical to the drilling mud composition pressure at the level of lower edges (27) of lateral orifices (25). The pressure loss resulting from the flow-through slit (18) remains within clearly determinable limits as a result of the configuration of slit (18) as a small-diameter constricted segment.

This pressure which builds up when auxiliary valve (13) and (14) in interior flow channel (21), (12), and (10) are closed exerts upward hydraulic forces on primary valve (4), whose sum (taking into consideration interior diameter (d3) of primary valve (4) which determines the hydraulically effective interior surface) exceeds the downward hydraulic forces acting on primary valve (4), including the gravitational forces applied to the latter.
This sum of the axially downward directed hydraulic forces on primary valve (4) is determined by the starting position of primary valve (4) according to Figure 2, taking into account the exterior diameter (âl) which determines the hydraulically effective exterior surface, and the sum consists of static and dynamic forces since ~ 3.~

primary valve (4) is constantly surrounded by the flo~ of drilling mud composition.

Immediately after closing auxlliary valve ll3) and (14), primary valve (4) consequently moves upward with an acceleration due to the difference in axial forces. This upward motion modifies the hydraulic forces which act on primary valve (4) since the upward motion results in a change in the flow cross section and the flow conditions in constricted segment (29).

In the execution example shown, diameters (dl) and (d3) are selected with respect to each other and with respect to diameter (d2) so that the resultant downward lS force is relatively small when primary valve (4) starts to move upward after the closing of auxiliary valve (13) and (14) from its starting position. The force then increases at first as the pulse height increases, then decreases until it equals zero. In the position at which the sum of all forces acting on primary valve (4) is zero, primary valve (4) assumes its pressure-pulse-determining final operational position shown in Figure 3, which shows that in this position the lower edge (27) of lateral orifice (25) is located upstream from constriction area (7) of the exterior part. If auxiliary valve (13) and (14) is subsequently opened again, the force relation is again reversed, and primary valve (4) returns to its starting position, as shown in Figure 2.

The force relationships acting on primary valve (4) during the upward and the downward movement can be regulated by the selection of related diameters (dl), (d2) and (d3), which determine the static hydraulic fundamentals, by the selection of the position of lower edge (27) of lateral flow orifices (25) to constricted area (7) of exterior part (3), which can determine the 13~ 6~
interior pressure in primary valve (4) and its change with upward movement, and by the shaping of the transition areas (23) and (28), which affect the dynamic forces via the flow behavior in constricted segment (29). As a result of this regulation of the forces acting on it, primary valve (4) approaches its operational final positions, the starting position and the operational final position relatively slowly and leaves them relatively slowly, while in the intermediate area, the valve undergoes relatively rapid upward and downward motions.
This feature is desirable to avoid excess swing of the primary valve beyond the operational final position, to eliminate as much as possible percussive effects during the upward movement and to allow short pressure pulse generation times.

Claims (7)

1. Apparatus for generating pressure pulses in a fluid within a drill string, comprising:

an exterior member adapted to couple within said drill string, an interior valve member located generally coaxially within said exterior member and establishing a first fluid flow channel between said interior and exterior members, said interior valve member further comprising a second flow channel for the flow of fluid, said valve member movable between at least first and second positions, said first position defined by a stop against the flow direction of said fluid, said second position determined at least in part by an equilibrium in fluid forces in said first and second flow channels acting on said interior valve member.
2. The apparatus of claim 1, wherein said pressure differential is controlled through operation of an auxiliary valve operatively coupled in said second flow channel of said interior valve member.
3. The apparatus of claim 1, wherein said first fluid flow channel includes a restriction which is variable in cross-section in response to the position of said interior valve member relative to said exterior member.
4. The apparatus of claim 1, further comprising a stationary support, said stationary support at least partially coextensive with said interior valve member, said support cooperating with said interior valve member to define a cylindrical slit therebetween.
5. The apparatus of claim 4, wherein said stationary support further forms a portion of said auxiliary valve.
6. The apparatus of claim 5, wherein said stationary support functions as the valve seat for said auxiliary valve.
7. An apparatus for generating pressure pulses in a fluid within a drill string, comprising:

an exterior assembly adapted to couple within said drill string;

an interior member cooperatively adapted with said exterior assembly to define a variable cross-section flow path through said apparatus, said interior valve member having interior and exterior surfaces exposed to fluid flow, and being movably responsive into a pressure differential acting upon said interior and exterior surfaces; and an auxiliary valve cooperatively arranged with said interior and exterior valve members to selectively establish a pressure differential between said interior and exterior surfaces of said interior valve member.
CA000566212A 1987-05-09 1988-05-06 Apparatus for the generation of pressure pulses in drilling mud compositions Expired - Lifetime CA1316702C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP3715514.8 1987-05-09
DE3715514A DE3715514C1 (en) 1987-05-09 1987-05-09

Publications (1)

Publication Number Publication Date
CA1316702C true CA1316702C (en) 1993-04-27

Family

ID=6327176

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000566212A Expired - Lifetime CA1316702C (en) 1987-05-09 1988-05-06 Apparatus for the generation of pressure pulses in drilling mud compositions

Country Status (4)

Country Link
US (1) US4901290A (en)
EP (1) EP0290939B1 (en)
CA (1) CA1316702C (en)
DE (1) DE3715514C1 (en)

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US8203908B2 (en) 2004-04-06 2012-06-19 Newsco Directional Support Services Inc. Intelligent efficient servo-actuator for a downhole pulser

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US5103430A (en) * 1990-11-01 1992-04-07 The Bob Fournet Company Mud pulse pressure signal generator
DE19607402C1 (en) * 1996-02-28 1997-07-10 Welldone Engineering Gmbh Device for transmitting information within a drill pipe string of a drilling device by means of pressure pulses in a flowing liquid, in particular drilling fluid
US5836353A (en) * 1996-09-11 1998-11-17 Scientific Drilling International, Inc. Valve assembly for borehole telemetry in drilling fluid
DE10007647C2 (en) * 2000-02-19 2003-02-13 Karlsruhe Forschzent Method and device for transmitting data into a borehole during a drilling or expanding process
US6898150B2 (en) * 2001-03-13 2005-05-24 Baker Hughes Incorporated Hydraulically balanced reciprocating pulser valve for mud pulse telemetry
US7417920B2 (en) * 2001-03-13 2008-08-26 Baker Hughes Incorporated Reciprocating pulser for mud pulse telemetry
US7180826B2 (en) * 2004-10-01 2007-02-20 Teledrill Inc. Measurement while drilling bi-directional pulser operating in a near laminar annular flow channel
US7719439B2 (en) * 2006-06-30 2010-05-18 Newsco Directional And Horizontal Drilling Services Inc. Rotary pulser
US8138943B2 (en) * 2007-01-25 2012-03-20 David John Kusko Measurement while drilling pulser with turbine power generation unit
US7836948B2 (en) 2007-05-03 2010-11-23 Teledrill Inc. Flow hydraulic amplification for a pulsing, fracturing, and drilling (PFD) device
EP2148975B1 (en) * 2007-05-03 2019-03-20 David John Kusko Flow hydraulic amplification for a pulsing, fracturing, and drilling (pfd) device
US7958952B2 (en) * 2007-05-03 2011-06-14 Teledrill Inc. Pulse rate of penetration enhancement device and method
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US9702204B2 (en) 2014-04-17 2017-07-11 Teledrill, Inc. Controlled pressure pulser for coiled tubing measurement while drilling applications
US10633968B2 (en) 2011-12-23 2020-04-28 Teledrill, Inc. Controlled pressure pulser for coiled tubing measurement while drilling applications
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Publication number Priority date Publication date Assignee Title
US8203908B2 (en) 2004-04-06 2012-06-19 Newsco Directional Support Services Inc. Intelligent efficient servo-actuator for a downhole pulser

Also Published As

Publication number Publication date
EP0290939A3 (en) 1990-08-01
EP0290939A2 (en) 1988-11-17
EP0290939B1 (en) 1992-03-04
US4901290A (en) 1990-02-13
DE3715514C1 (en) 1988-09-08

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