FIELD OF DISCLOSURE
[0001] The current invention includes an apparatus and a method for creating a pulse within
the drilling fluid, generally known as drilling mud, that is generated by selectively
initiating flow driven bidirectional pulses within a bore pipe. Features of the device
include operating a flow throttling device (FTD) that operates without a centrally
located valve guide within a newly designed annular flow channel, such that the annular
flow channel provides an increased area for the flow of the drilling fluid and also
allows for the addition of an intelligent computerized control system using a combination
of hardware and software tools with downlink capability. The downlink tools may be
located above or below a positive displacement motor. The intelligent control system
provides and maintains several parameters that effect drilling or other downhole activity
efficiency (i.e. Weight on Bit, Rate of Penetration, Pulse Amplitude, Axial Vibration,
Borehole Pressure, etc.) by utilizing a feedback control loop such that the pressure
differentials within the collar and associated annulus of the FTD inside a bore pipe
provide information for properly controlled, reproducible pressure pulses that exhibit
little or no associated signal noise. The pulse received "up hole" from the tool down
hole includes a series of dynamic pressure changes that provide pressure signals which
can be used to interpret inclination, azimuth, gamma ray counts per second, etc. by
oilfield personnel. These dynamic pressure changes and resulting signals are utilized
to further increase yield in oilfield operations. The system according to the preamble
part of claim 1 is disclosed in
US 2005/0260089 A1.
BACKGROUND
[0002] Current pulser technology utilizes pulsers that are sensitive to different fluid
pump down hole pressures, and flow rates, and require field adjustments to pulse properly
so that meaningful signals from these pulses can be received and interpreted uphole.
[0003] US 2005/0260089 A1 discloses a method of transmitting pressure pulses from a downhole location through
a flowing fluid in a wellbore. A linear actuator is used to controllably move a reciprocating
member axially back and forth between a first position and a second position to at
least partially obstruct flow of the flowing fluid to generate the pressure pulses.
A reciprocating pulser for generating pressure pulses in a fluid flowing in a wellbore,
comprises a fluid passage that allows flow of the fluid through the pulser, and a
reciprocating member. A linear actuator is coupled to the reciprocating member, such
that the linear actuator moves the reciprocating member in a first axial direction
and then in a reverse direction to at least partially obstruct flow of the fluid through
the pulser to generate pressure pulses in the flowing fluid.
[0004] An important advantage of the present disclosure and the associated embodiments is
that it decreases sensitivity to fluid flow rate or pressure within easily achievable
limits, does not require field adjustment, and is capable of creating recognizable,
repeatable, reproducible, yet controlled, clean (i.e. noise free) fluid pulse signals
using minimum power due to a unique flow throttling device (FTD) with a pulser that
requires no guide, guide pole or other guidance system to operate the main valve,
thus reducing wear, clogging and capital investment of unnecessary equipment as well
as increasing longevity and dependability in the down hole portion of the MWD tool.
This MWD tool still utilizes battery, magneto-electric and/or turbine generated energy.
The mostly unobstructed main flow in the main flow area enters with full flow into
the cone without altering the main flow pattern. The increased flow rate and change
in pressure produces a very efficient pilot valve response and associated energy pulses.
Specifically, as the pilot valve closes faster (than in any known previous designs)
this produces large pressure spike similar to a "water hammer" effect much like that
is heard when shutting off a water faucet extremely quickly. The faster flow and corresponding
larger pressure differential also moves the pilot valve into an open and closed position
more rapidly. The faster the closure, the more pronounced the water hammer effect
and the larger the pulse and associated measured spike associated with the pulse.
These high energy pulses are also attributed to the position and integrity of the
pilot channel seals (240) which ensure rapid and complete closure while maintaining
complete stoppage of flow through the channel.The controllability of the pulser is
also significantly enhanced in that the shape of the pressure wave generated by the
energy pulse can be more precisely predetermined. The pulse rise and fall time is
sharp and swift - much more so than with conventional devices utilizing guide pole
designs. These more easily controlled and better defined energy pulses are easily
distinguished from the background noise associated with MWD tools. Distinguishing
from the "background" noise leading to ease of decoding signals occurring on an oil
or gas rig offers tremendous advantages over current tools. By implementing the feedback
control by utilizing sensors to detect pulse responses, the pulser can be programmed
to operate intelligently responding based on measured sensor parameters using preprogrammed
logic. Being able to control and determine pulse size, timing, and shape without ambiguity
provides the user with reproducible, reliable data that results in reduced time on
the rig for analysis and more reliable and efficient drilling.
[0005] US Patents 7,180,826 and
US Application Number 2007/0104030A1 to Kusko, et. al., disclose a fully functional pulser system that requires the use of a pulser
guide pole to guide and define the movement of the main valve together with a different
hydraulic channel designs than that of the present application and associated invention.
SUMMARY
[0006] The present disclosure involves the placement of a Measurement-While-Drilling (MWD)
pulser device including a flow throttling device located within a bore pipe in a wellbore
incorporating drilling fluids for directional and intelligent drilling. In the design,
the pilot channel location is very different than in any prior application in that
the channel is now located on the outside annulus. Features of the device include
operating a flow throttling device (FTD) that operates without a centrally located
valve guide within a newly designed annular flow channel, such that the annular flow
channel provides an increased area for the flow of the drilling fluid and also allows
for the addition of an intelligent computerized control system using a combination
of hardware and software tools with downlink capability. The downlink tools may be
located above or below a positive displacement motor. The intelligent control system
provides and maintains several parameters that effect drilling or other downhole activity
efficiency (i.e. Weight on Bit, Rate of Penetration, Pulse Amplitude, Axial Vibration,
Borehole Pressure, etc.) by utilizing a feedback control loop such that the pressure
differentials within the collar and associated annulus of the FTD inside a bore pipe
provide information for properly guided, reproducible pressure pulses that exhibit
little or no associated signal noise. The pulse received "up hole" from the tool down
hole includes a series of dynamic pressure changes that provide pressure signals which
can be used to interpret inclination, azimuth, gamma ray counts per second, etc. by
oilfield personnel. These dynamic pressure changes and resulting signals are utilized
to further increase yield in oilfield operations. The present invention also discloses
a novel device for creating pulses in drilling fluid media flowing through a drill
string. Past devices, currently in use, require springs or solenoids to assist in
creating pulses and are primarily located in the main drilling fluid flow channel.
US Patents 7,180,826 and
US Application Number 2007/0104030A1 to Kusko, et. al., disclose a fully functional pulser system that requires the use of a pulser guide
pole to guide and define the movement of the main valve together with a different
hydraulic channel designs than that of the present application and associated invention.
The pilot flow for the present invention without the guide pole allows for more efficient
repair and maintenance processes and also allows for quickly replacing the newly designed
apparatus of the present disclosure on the well site as there is at least a 15-20
percent reduction in capital costs and the costs on the maintenance side are drastically
reduced. In the previous designs, guide pole failures accounted for 60-70 percent
of the downhole problems associated with the older versions of the MWD. With the guide
pole elimination, reliability and longer term down hole usage increases substantially,
providing a more robust tool and much more desirable MWD experience.
[0007] Additionally, previous devices also required onsite adjustment of the flow throttling
device (FTD) pulser according to the flow volume and fluid pressure and require higher
energy consumption due to resistance of the fluid flow as it flows through an opened
and throttled position in the drill collar.
[0008] The elimination of the centralized guide pole and pilot channel allows, in the current
design, larger pressure differential to be created between the pilot flow and the
main flow at the main valve thus increasing the control and calibration and operation
of the pulser. The ability to precisely control the pulser and thus the pressure pulse
signals is directly related to cleaner, more distinguishable and more defined signals
that can be easier detected and decoded up hole.
[0009] Additional featured benefits of the present inventive device and associated methods
include having a pulser tool above and/or below the PDM (positive displacement motor)
allowing for intelligence gathering and transmitting of real time data by using the
pulser above the motor and as an efficient drilling tool with data being stored in
memory below the motor with monitored borehole pressure, acceleration, as well as
downhole WOB control, among other drilling parameters. Drilling parameter control
is accomplished by using a set point and threshold for the given parameter and adjusting
based on effects provided by the shock wave generated using the FTD. Master control
is provided uphole or downhole with a feedback loop from the surface of the well or
from intelligent programming incorporated in the pulsing device in the BHA above and/or
below the PDM.
[0010] The device provided by the current invention allows for the use of a flow throttling
device that moves from an initial position to an intermediate and final position in
both the upward and downward direction corresponding to the direction of the fluid
flow. The present invention still avoids the use of springs, the use of which are
described in
U.S. Pat. No's 3,958,217,
4,901,290, and
5,040,155.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
Figure 1 is an overview of the full flow MWD with feedback control.
Figure 2 is a close up of the pilot flow screen assembly
Figure 3 is a detailed cross section of the main valve actuator assembly including
the seals.
Figure 4 shows the lower portion of the pilot actuator assembly, drive shaft and motor.
Figure 5 is a pulser feedback control flow diagram.
DETAILED DESCRIPTION OF THE DRAWINGS
[0012] With reference now to Figure 1, the pulser assembly 400 device illustrated produces
pressure pulses in drilling fluid main flow 110 flowing through a tubular hang-off
collar 120 and includes a pilot flow upper annulus 160. The flow cone 170 is secured
to the inner diameter of the hang off collar 120. Major assemblies of the MWD are
shown as provided including aligned within the bore hole the pilot flow screen assembly
135 and main valve actuator assembly 229 and pilot actuator assembly 335.
[0013] In Figure 1, starting from an outside position and moving toward the center of the
main valve actuator assembly 226 comprising a main valve 190, a main valve pressure
chamber 200, a main valve support block 350, main valve seals 225 and flow guide seal
240. The same figure shows the main valve feed channel 220, the pilot orifice 250,
pilot valve 260, pilot flow shield 270, bellows 280 and the anti-rotation block 290,
as well as a cylindrical support shoulder 325 and tool face alignment key 295 that
exists below the pilot flow shield 270 for keeping the pulser assembly centered within
the bore hole. This figure also shows the passage of the main flow 110 past the pilot
flow screen 130 through the main flow entrance 150, into the flow cone 170, through
the main orifice 180 into and around the main valve 190, past the main valve pressure
chamber 200, past the main valve seals 225 through the main valve support block 350,
after which it combines with the pilot exit flow 320 to become the main exit flow
340. The pilot flow 100 flows through the pilot flow screen 130 into the pilot flow
screen chamber 140, through the pilot flow upper annulus 160, through the pilot flow
lower annulus 210 and into the pilot flow inlet channel 230, where it then flows up
into the main valve feed channel 220 until it reaches the main valve pressure chamber
200 where it flows back down the main valve feed channel 220, through the pilot flow
exit channel 360, through the pilot orifice 250, past the pilot valve 260 where the
pilot exit flow 320 flows over the pilot flow shield 270 where it combines with the
main flow 110 to become the main exit flow 340 as it exits the pilot valve support
block 330 and flows on either side of the rotary magnetic coupling 300, past the drive
shaft and the motor 310.
[0014] The pilot actuator assembly 335 includes a magnetic pressure cup 370, and encompasses
the rotary magnetic coupling 300. The magnetic pressure cup 370 and the rotary magnetic
coupling 300 may comprise several magnets, or one or more components of magnetic or
ceramic material exhibiting several magnetic poles within a single component. The
magnets are located and positioned in such a manner that the rotatry movement or the
magnetic pressure cup 370 linearly and axially moves the pilot valve 260. The rotary
magnetic coupling 300 is actuated by the adjacent drive shaft 305.
[0015] Figure 2 provides details of the pulser assembly in the open position; the pilot
flow 100 and main flow 110 both flow through the pilot flow screen assembly 135 and
pilot flow screen 130 where a portion of the main flow 110 flows through the pilot
flow screen 130. The pilot flow 100 flows through the pilot flow screen chamber 140
and into the pilot flow upper annulus 160. Pilot flow 100 and main flow 110 within
the pilot flow screen assembly 135 flows through the main flow entrance 150 and through
the flow cone 170 and into the main orifice 180 to allow for flow within the main
valve feed channel 220.
[0016] Figure 3 describes the main valve actuator assembly 229 and illustrates the flow
of the pilot flow 100 and main flow 110 areas with the main valve 190 in open position.
The main flow 110 passes through openings in the main valve support block 350 while
the pilot flow 100 flows through the pilot flow lower annulus 210, into the pilot
flow inlet channel 230 and into the main valve feed channel 220 which puts pressure
on the main valve pressure chamber 200 when the pilot valve 260 is in closed position.
The pilot flow 100 then flows out through the pilot flow exit channel 360, through
the pilot orifice 250 and over the pilot valve 260. Also shown are the seals 225,
226, 227, 228 &240 of the main valve actuator assembly.
[0017] When pilot valve 260 closes, pressure increases through the main valve feed channel
220 into the main valve pressure chamber 200. The upper outer seal 227, upper inner
seal 225, lower inner seal 226, lower outer seal 228 and flow guide seal 240 keep
the pilot flow 100 pressure constrained and equal to the pressure that exists in main
flow entrance 150 area.
[0018] Upper outer seal 227 and lower outer seal 228 exclude large particulates from entering
into the space where the upper inner seal 225 and lower inner seal 226 reside. The
upper outer seal 227 and lower outer seal 228 do not support a pressure load and allow
a small amount of pilot flow 100 to bypass while excluding particulates from entering
the area around the upper inner seal 225 and lower inner seal 226. This eliminates
pressure locking between the inner seals 225, 226 and the outer seals 227, 228. By
excluding the particulates from entering into the space where the inner seals reside
225, 226 the seals are protected and the clearances of the inner seals 225, 226 can
be reduced to support high pressure loads. Very small particulates can bypass the
outer seals 227, 228, but the particulates must be very small in relative to the clearances
of the inner seals 225, 226 to penetrate the space between the outer seals 227, 228
and inner seals 225, 226.
[0019] Referring to Figure 4, an embodiment of the rotary magnetic coupling 300 and motor
310 is shown. The Main exit flow 340 flows parallel along each side of the rotary
magnetic coupling 300 which is contained within the magnetic pressure cup 370, past
the drive shaft and parallel along each side of the motor 310 down toward the cylindrical
support shoulder 325 that includes a tool face alignment key 295 below the pilot flow
shield 270. The magnetic pressure cup 370 is comprised of a non-magnetic material,
and is encompassed by the outer magnets 302. The outer magnets 302 may comprise several
magnets, or one or more components of magnetic or ceramic material exhibiting several
magnetic poles within a single component. The outer magnets 302 are housed in an outer
magnet housing 303 that is attached to the drive shaft. Within the magnetic pressure
cup 370 are housed the inner magnets 301 which are permanently connected to the pilot
valve 260.
[0020] The outer magnets 302 and the inner magnets 301 are placed so that the magnetic polar
regions interact, attracting and repelling as the outer magnets 302 are moved about
the inner magnets 301 The relational combination of magnetic poles of the moving outer
magnets 302 and inner magnets 301, causes the inner magnets 301 to move the pilot
valve 260 linearly and interactively without rotating. The use of outer magnets 302
and inner magnets 301 to provide movement from rotational motion to linear motion
also allows the motor 310 to be located in an air atmospheric environment in lieu
of a lubricating fluid environment. This also allows for a decrease in the cost of
the motor 310, decreased energy consumption and subsequently decreased cost of the
actual MWD device. It also alleviates the possibility of flooding the sensor area
of the tool with the drilling fluid like in the use of a moving mechanical seal.
[0021] The information flow on the Pulser Control Flow Diagram in Fig. 5 details the controllable
pulser operation sequence. The drilling fluid pump, known as the mud pump 500 is creating
the flow with a certain base line pressure. That fluid pressure is contained in the
entirety of the interior 510 of the drill string, known as the bore pressure. The
bore pipe pressure sensor 420 is sensing this pressure increase when the pumps turn
on, and send that information to the Digital Signal Processor (DSP) 540 which interprets
it. The DSP 540 also receives information from the annulus pressure sensor 470 which
senses the drilling fluid (mud) pressure 520 as it returns to the pump 500 in the
annulus 520 (outside) of the drill pipe. Based on the pre-programmed logic 530 in
the software of the DSP 540, and on the input of the two pressure sensors 420, 470
the DSP 540 determines the correct pulser operation settings and sends that information
to the pulser motor controller 550. The pulser motor controller 550 adjusts the stepper
motor 310 current draw, response time, acceleration, duration, revolution, etc. to
correspond to the pre-programmed pulser settings 530 from the DSP 540. The stepper
motor 310 driven by the pulser motor controller 550 operates the pilot actuator assembly
335 from Fig. 1. The pilot actuator assembly 335, responding exactly to the pulser
motor controller 550, opens and closes the main valve 190, from Fig. 1, in the very
sequence as dictated by the DSP 540. The main valve 190 opening and closing creates
pressure variations of the fluid pressure in the drill string on top of the bore pressure
which is created by the mud pump 500. The main valve 190 opening and closing also
creates pressure variations of the fluid pressure in the annulus 520 of the drill
string on top of the base line annulus pressure because the fluid movement restricted
by the main valve 190 affects the fluid pressure downstream of the pulser assembly
400 through the drill it jets into the annulus 520 of the bore hole. Both the annulus
pressure sensor 470 and the bore pipe pressure sensor 420 detecting the pressure variation
due to the pulsing and the pump base line pressure sends that information to the DSP
540 which determines the necessary action to be taken to adjust the pulser operation
based on the pre-programmed logic.
Operation - operational pilot flow - all when the pilot is in the closed position;
[0022] The motor 310 rotates the rotary magnetic coupling 300 which transfers the rotary
motion to linear motion of the pilot valve 260 by using an anti-rotation block 290.
The mechanism of the rotary magnetic coupling 300 is immersed in oil and is protected
from the drilling fluid flow by a bellows 280 and a pilot flow shield 270. When the
motor 310 moves the pilot valve 260 forward (upward in Figure 1) into the pilot orifice
250, the pilot fluid flow is blocked and backs up as the pilot fluid in the pilot
flow exit channel 360, pilot flow inlet channel 230 and in the pilot flow upper annulus
160 all the way back to the pilot flow screen 130 which is located in the lower velocity
flow area due to the larger flow area of the main flow 110 and pilot flow 100 where
the pilot flow fluid pressure is higher than the fluid flow through the main orifice
180. The pilot fluid flow 100 in the pilot flow exit channel 360 also backs up through
the main valve feed channel 220 and into the main valve pressure chamber 200. The
fluid pressure in the main valve pressure chamber 200 is equal to the main flow 110
pressure, but this pressure is higher relative to the pressure of the main fluid flow
in the main orifice 180 in front portion of the main valve 190. This differential
pressure between the pilot flow flow in the main valve pressure chamber 200 area and
the main flow through the main orifice 180 into the main orifice 180 causes the main
valve 190 to act like a piston and to move toward closure still upward in Figure 1
causing the main orifice 180 to stop the flow of the main fluid flow 110 causing the
main valve 190 to stop the main fluid flow 110 through the main orifice 180. As the
drilling fluid main flow 110 stops at the main valve 190 its pressure increases. Since
the pilot flow lower annulus 210 extends to the bore pipe pressure inlet 410 located
in the pilot valve support block 330 the pressure change in the pilot fluid flow reaches
the bore pipe pressure sensor 420 which transmits that information through the electrical
connector 440 to the pulser control electronics DSP 450. The pulser controlling electronics
DSP 450 together with pressure data from the annulus pressure sensor 470 adjusts the
pilot valve operation based on pre-programmed logic to achieve the desired pulse characteristics.
Opening operation
[0023] When the motor 310 moves the pilot valve 260 away downward in Figure 1 from the pilot
orifice 250 allowing the fluid to exit the pilot exit flow 320 and pass from the pilot
flow exit channel 360 relieving the higher pressure in the main valve pressure chamber
200 this causes the fluid pressure to be reduced and the fluid flow to escape. In
this instance, the main fluid flow 110 is forced to flow through the main orifice
180 to push open (downward in Figure 1) the main valve 190, thus allowing the main
fluid 110 to bypass the main valve 190 and to flow unencumbered through the remainder
of the tool.
Pilot Valve in the Open Position
[0024] As the main flow 110 and the pilot flow 100 enter the main flow entrance 150 and
combined flow through into the flow cone area 170, by geometry (decreased cross-sectional
area), the velocity of the fluid flow increases. When the fluid reaches the main orifice
180 the fluid flow velocity is increased (reducing the pressure and increasing the
velocity) and the pressure of the fluid is decreased relative to the entrance flows
(main area vs. the orifice area) 180. When the pilot valve 260 is in the opened position,
the main valve 190 is also in the opened position and allows the fluid to pass through
the main orifice 180 and around the main valve 190, through the openings in the main
valve support block 350 through the pilot valve support block 330 and subsequently
into the main exit flow 340.
[0025] The information flow on the Pulser Control Flow Diagram in Fig. 5 details the controllable
pulser operation sequence. The drilling fluid pump, known as the mud pump 500 is creating
the flow with a certain base line pressure. That fluid pressure is contained in the
entirety of the interior 510 of the drill string, known as the bore pressure. The
bore pipe pressure sensor 420 is sensing this pressure increase when the pumps turn
on, and sends that information to the Digital Signal Processor (DSP) 540 which interprets
it. The DSP 540 also receives information from the annulus pressure sensor 470 which
senses the drilling fluid (mud) pressure 520 as it returns to the pump 500 in the
annulus 520 (outside) of the drill pipe. Based on the pre-programmed logic 530 in
the software of the DSP 540, and on the input of the two pressure sensors 420, 470
the DSP 540 determines the correct pulser operation settings and sends that information
to the pulser motor controller 550. The pulser motor controller 550 adjusts the stepper
motor 310 current draw, response time, acceleration, duration, revolution, etc. to
correspond to the pre-programmed pulser settings 530 from the DSP 540. The stepper
motor 310 driven by the pulser motor controller 550 operates the pilot actuator assembly
335 as shown in Fig. 1. The pilot actuator assembly 335, responds directly to the
pulser motor controller 550, and opens and closes the main valve 190, again shown
in Fig. 1, in the sequence dictated by the DSP 540. The main valve 190 opening and
closing creates pressure variations of the fluid pressure in the drill string in addition
to the bore pressure which is created by the mud pump 500. The main valve 190 opening
and closing also creates pressure variations or fluctuations of the fluid pressure
in the annulus 520 of the drill string in addition to the base line annulus pressure
because the fluid movement restricted by the main valve 190 affects the fluid pressure
downstream of the pulser assembly 400 through the drill as the fluid jets into the
annulus 520 of the bore hole. Both the annulus pressure sensor 470 and the bore pipe
pressure sensor 420 detect the pressure variations exhibited by the pulsing pressures
and the pump base line pressure. These variations provide signals that are sent as
data information to the DSP 540 that determines the necessary action to be taken to
adjust the pulser operation based on any pre-programmed logic provided.
DETAILED DESCRIPTION
[0026] The present invention will now be described in greater detail and with reference
to the accompanying drawings. With reference now to Figure 1, the device illustrated
produces pressure pulses for pulsing of the pulser within a main valve actuator assembly
of the flow throttling device (FTD) in the vertical upward and downward direction
using drilling fluid that flows through a tubular rental collar and an upper annulus
which houses the pilot flow. There is a flow cone secured to the inner diameter of
a hang off collar with major assemblies of the MWD that include a pilot flow screen
assembly, a main valve actuator assembly, and a pilot actuator assembly.
[0027] To enable the pulser to move in a pulsing upward and downward direction, the passage
of the main flow of the drilling fluid flows through the pilot flow screen into the
main flow entrance then into the flow cone section and through the main orifice and
main valve past the main valve pressure chamber, past the seals, and finally into
and through the main valve support block with the flow seal guide.
[0028] At this point, the initial drilling fluid combines with the pilot exit fluid and
together results in the exit flow of the main fluid. The pilot fluid flow continues
flowing through the pilot flow screen and into the pilot flow screen chamber then
through the pilot flow upper annulus section, the pilot flow lower annulus section
and into the pilot flow inlet channel where the fluid flows upward into the main valve
feed channel until it reaches the main valve pressure chamber causing upward motion
of the pulser. There, the fluid flows back down the main valve feed channel through
the pilot flow exit channel and through the pilot orifice and pilot valve at which
point the fluid exits the pilot area where it flows over the pilot flow shield and
combines with the main flow to comprise the main exit flow as it exits the pilot valve
support block and flows down both sides of the rotary magnetic coupling, outside the
magnetic pressure cup and eventually past the drive shaft and the motor.
[0029] In operation to accomplish the task of providing for the pilot to attain the closed
position, the motor rotates the rotary magnetic coupling transfers rotary motion to
linear motion of the pilot valve by using an anti-rotation block. The mechanism of
the rotary magnetic coupling is protected from the fluid flow by the use of a bellows
and a pilot flow shield. When the motor moves the pilot valve forward - upward into
the pilot orifice -the pilot valve blocks and backs up the pilot fluid in the pilot
flow exit channel, the pilot flow inlet channel, and in the pilot flow upper annulus,
such that the fluid back up and reaches all the way back to the pilot flow screen
(which is located in the lower velocity flow area due to the geometry of the larger
flow area of the main flow and pilot flow sections such that the pilot flow fluid
pressure is higher than the fluid flow through the main orifice).
[0030] The pilot fluid flow in the pilot flow exit channel also backs up through the main
valve feed channel and into the main valve pressure chamber. The fluid pressure in
the main valve pressure chamber is now equal to the main flow pressure but the fluid
pressure is higher relative to the pressure of the main fluid flow in the main orifice
in the front portion of the main valve. The differential pressure between the pilot
flow and the main flow through the main orifice causes the main valve to act like
a piston and moves toward closure of the main orifice (upward direction in the Figures
provided), thereby causing the main valve to provide a stoppage of the flow of the
main fluid flow within the main orifice.
[0031] In another embodiment, the MWD device utilizes a turbine residing near and within
the proximity of a flow diverter. The flow diverter diverts drilling mud in an annular
flow channel into and away from the turbine blades such that the force of the drilling
mud causes the turbine blades and turbine to rotationally spin around an induction
coil. The induction coil generates electrical power for operating the motor and other
instrumentation mentioned previously. The motor is connected to the pilot actuator
assembly via a drive shaft. The pilot actuator assembly comprises a magnetic coupling
and pilot assembly. The magnetic coupling comprises outer magnets placed in direct
relation to inner magnets located within the magnetic pressure cup or magnetic coupling
bulkhead. The magnetic coupling translates the rotational motion of the motor, via
the outer magnets to linear motion of the inner magnets via magnetic polar interaction.
The linear motion of the inner magnets moves the pilot assembly, comprising the pilot
shaft, and pilot valve, linearly moving the pilot into the pilot seat. This action
allows for closing the pilot seat, pressurizing the flow throttling device, closing
the flow throttling device orifice, thereby generating a pressure pulse. Further rotation
of the motor, drive shaft, via the magnetic coupling, moves the pilot assembly and
pilot away from the pilot seat, depressurizing the flow throttling device sliding
pressure chamber and opening the flow throttling device and completing the pressure
pulse. Identical operation of the pilot into and out of the pilot seat orifice can
also be accomplished via linear to linear and also rotation to rotation motions of
the outer magnets in relation to the inner magnets such that, for example, rotating
the outer magnet to rotate the inner magnet to rotate a (rotating) pilot valve causing
changes in the pilot pressure, thereby pushing the FTD (flow throttling device) up
or down.
[0032] Unique features of the pulser include the combination of middle and lower inner flow
channels, flow throttling device, bellows, and upper and lower flow connecting channels
possessing angled outlet openings that helps create signals transitioning from both
the sealed (closed) and unsealed (open) positions. Additional unique features include
a flow cone for transitional flow and a sliding pressure chamber designed to allow
for generation of the pressure pulses. The flow throttling device slides axially on
a pulser guide pole being pushed by the pressure generated in the sliding pressure
chamber when the pilot is in the seated position. Additional data (and increased bit
rate) is generated by allowing the fluid to quickly back flow through the unique connecting
channel openings when the pilot is in the open position. Bi-directional axial movement
of the poppet assembly is generated by rotating the motor causing magnets to convert
the rotational motion to linear motion which opens and closes the pilot valve. The
signal generated provides higher data rate in comparison with conventional pulsers
because of the bi-directional pulse feature. Cleaner signals are transmitted because
the pulse is developed in near-laminar flow within the uniquely designed flow channels
and a water hammer effect due to the small amount of time required to close the flow
throttling device.
[0033] The method for generating pressure pulses in a drilling fluid flowing downward within
a drill string includes starting at an initial first position wherein a pilot (that
can seat within a pilot seat which resides at the bottom of the middle inner flow
channel) within a lower inner flow channel is not initially engaged with the pilot
seat. The pilot is held in this position with the magnetic coupling. The next step
involves rotating the motor causing the magnetic fields of the outer and inner magnets
to move the pilot actuator assembly thereby moving the pilot into an engaged position
with the pilot seat. This motion seals a lower inner flow channel from the middle
inner flow channel and forces the inner fluid into a pair of upper connecting flow
channels, expanding the sliding pressure chamber, causing a flow throttling device
to move up toward a middle annular flow channel and stopping before the orifice seat,
thereby causing a flow restriction. The flow restriction causes a pressure pulse or
pressure increase transmitted uphole. At the same time, fluid remains in the exterior
of the lower connecting flow channels, thus reducing the pressure drop across the,
pilot seat. This allows for minimal force requirements for holding the pilot in the
closed position. In the final position, the pilot moves back to the original or first
position away from the pilot orifice while allowing fluid to flow through the second
set of lower connecting flow channels within the lower inner flow channel. This results
in evacuating the sliding pressure chamber as fluid flows out of the chamber and back
down the upper flow connecting channels into the middle inner flow channel and eventually
into the lower inner flow channel. As this occurs, the flow throttling device moves
in a downward direction to open along the same direction as the flowing drilling fluid
until motionless. This decreases the FTD created pressure restriction of the main
drilling fluid flow past the flow throttling device orifice completing the pulse.
[0034] An alternative embodiment includes the motor connected to a drive shaft through a
mechanical device such as a worm gear, barrel cam face cam or other mechanical means
for converting the rotational motion of the motor into linear motion to propel the
pilot actuator assembly.
Opening operation
[0035] When the pilot valve moves away (downward in the vertical direction) into the pilot
orifice allowing the fluid to flow through the pilot exit and pass from the pilot
flow exit channel causing relief of the higher pressure in the main valve pressure
chamber. This allows for the pressure to be reduced and the fluid to escape the chamber.
The fluid is then allowed to flow into the main fluid flow and flow through the main
orifice pushing open (downward) or opening the main valve, thus allowing the main
fluid to by pass the main valve and to flow unencumbered through the remainder of
the tool.
[0036] When the main flow and pilot flow enters the main flow entrance and flows through
into the flow cone area where the velocity of the fluid flow increases such that the
fluid reaches the main orifice and the fluid flow velocity is increased (reducing
the pressure and increasing the velocity of the fluid). The pressure of the fluid
is decreased relative to the entrance flows (main area vs. the orifice area). When
the pilot valve is in the opened position, the main valve is also in the open position
and allows the fluid to pass through the main orifice and around the main valve and
through the openings in the main valve support block allowing for the fluid to flow
through the opening of the pilot and through the pilot valve support block. Subsequently
the fluid flows into the main exit flow channel.
[0037] With reference now to Figure 1, the device illustrated produces pressure pulses in
drilling fluid flowing through a tubular drill collar and upper annular drill collar
flow channel. The flow cone is secured to the inner diameter of the drill collar.
The centralizer secures the lower portion of the pulse generating device and is comprised
of a non-magnetic, rigid, wear resistant material with outer flow channels.
[0038] These conditions provide generation of pulses as the flow throttling device reaches
both the closed and opened positions. The present invention allows for several sized
FTD's to be placed in a drilling collar, thereby allowing for different flow restrictions
and/or frequencies which will cause an exponential increase in the data rate that
can be transmitted up hole.
[0039] Positioning of the main valve actuator assembly within the drill collar and utilizing
the flow cone significantly decreases the turbulence of the fluid and provides essentially
all laminar fluid flow. The linear motion of the flow throttling device axially is
both up and down (along a vertical axial and radial direction without the use of a
guide pole).
[0040] Conventional pulsers require adjustments to provide a consistent pulse at different
pressures and flow rates. The signal provided in conventional technology is by a pulse
that can be received up hole by use of a pressure transducer that is able to differentiate
pressure pulses (generated downhole). These uphole pulses are then converted into
useful signals providing information for the oilfield operators, such as gamma ray
counts per second, azimuth, etc. Another advantage of the present invention is the
ability to create a clean (essentially free of noise) pulse signal that is essentially
independent of the fluid flow rate or pressure within the drill collar. The present
invention thereby allows for pulses of varying amplitudes (in pressure) and frequencies
to significantly increase the bit rate.
[0041] An additional embodiment of the present invention includes a system comprising a
controllable pulser that operates sequentially within a downhole assembly such as
a drill pipe, that enhances operational efficiency in the removal of hydrocarbon deposits,
where the system comprises; a fluid, fluid flow, and a fluid drilling pump which when
combined creates fluid flow into a bore pipe annulus such that a base line bore pipe
pressure is created and such that fluid flow and bore pipe pressure is contained entirely
within a drill string and wherein bore pipe pressure increases and is measured with
one or more pressure sensors for sensing bore pipe pressure such that pressure sensor(s)
send information to a digital signal processor (DSP) that receives information in
the form of digital data from said pressure sensor(s), and wherein pulser utilize
computerized instructional software and hardware components included in the digital
signal processor (DSP) so that controllable sequential operation of the pulser is
obtained utilizing one or more pressure sensors located within a bore pipe annulus
located within an outer annular portion of the drill pipe.
[0042] The pre-programmed logic is embedded within the software components of the DSP such
that the input data supplied to the DSP by one or more pressure sensors correctly
determines pulser operation settings allowing for the sending of data that is subsequently
received and interpreted by the DSP for controlling a pulser motor controller, wherein
the motor controller controls adjustment of a stepper motor's current draw, response
time, acceleration, duration, and revolutions corresponding with pre-programmed pulser
settings provided by the software components of the DSP and wherein pulses are developed
with a pilot actuator assembly that identically match the pulses of the pulser motor
controller and operates the opening and closing of a main valve in a sequence dictated
by the DSP, thereby creating pressure variations of the fluid pressure resulting from
fluid flowing within the drill string and within the bore pipe.
[0043] The main valve opens and closes, thereby creating pressure variations of the fluid
pressure in the annulus of the drill string in addition to the base line bore pipe
pressure due to fluid flow movement restricted by the main valve, wherein the fluid
pressure is also affected downstream of the pulser assembly as the fluid flows through
a drill bit and jets within said bore hole pipe annulus.
1. A system comprising a controllable pulser that operates sequentially within a downhole
assembly within a drill string (510) of a drill pipe, that enhances operational efficiency
in the removal of hydrocarbon deposits, said system comprising; a drilling fluid,
fluid flow, and a fluid drilling pump which when combined creates fluid flow into
a bore pipe annulus within said downhole assembly such that a base line bore pipe
pressure is created wherein said bore pipe pressure is sensed via a sensor located
withinsaid controllable pulser sensing a pressure increase when said pump is operating
such that said sensor sends information to a Digital Signal Processor (DSP) (540)
also located within said controllable pulser that interprets said information and
wherein said DSP also receives information from an annulus pressure sensor (470) that
senses drilling fluid pressure as it returns to said pump in an annular outside portion
of said drill pipe such said DSP recognizes pressure variation inputs obtained from
said annulus pressure sensor (470) and said bore pipe pressure sensor (420) and detects
pressure variation exhibited between pulsing pressures and a pump base line pressure,
thereby providing signals that are sent as data information to said DSP such that
said DSP determines required action to properly adjust controllable pulser operation
settings and subsequently sends information to a pulser motor controller (550) that
adjusts a stepper motor (310) current draw, response time, acceleration, duration,
and number of revolutions corresponding to any pre-programmed pulser settings provided
by said DSP.
2. The system of claim 1, wherein pre-programmed logic (530) is embedded within software
components of said DSP such that the input data supplied to said DSP by one or more
pressure sensors correctly provides information that determines settings that define
the pulser operation in terms of number of pulses, amplitude of pulses, duration for
pulses and timing of pulses allowing for the sending of output data that is subsequently
received and interpreted by said DSP for precisely controlling said pulser motor controller
(550),
using a stepper motor (310) driven by said pulser motor controller (550) that operates
a pilot actuator assembly (335), said assembly responding directly to said pulser
motor controller (550) by opening and closing said main valve (190) of said controllable
pulser in a sequence dictated by said DSP.
3. The system of claim 1 or 2, wherein opening and closing said main valve (190) creates
pressure variations of said fluid pressure in said drill string (510) in addition
to a bore pressure, wherein said bore pressure is created by a mud pump (500) and
wherein opening and closing said main valve (190) also creates pressure variations
or fluctuations of a fluid pressure in an annulus of said drill string (510) in addition
to a base line annulus pressure (520) due to fluid movement restricted by said main
valve (190) which directly affects fluid pressure downstream of said controllable
pulser assembly (400) extending through a drill bit as said fluid jets into said bore
hole pipe annulus.
4. The system of one of the preceding claims, wherein said annulus pressure sensor (470)
and said bore pipe pressure sensor detect pressure variations due to pulsing in comparison
with a pump base line pressure wherein said pressure variations provide information
signals to said DSP to ensure required actions for adjustment of continued pulser
operation that also avoids excessive water hammer during opening and closing of said
main valve (190).
5. An apparatus for generating pressure pulses in a drilling fluid flowing and enhancing
completing a well bore within a coiled tubing assembly comprising: a flow throttling
device longitudinally and axially positioned within the center of a main valve actuator
assembly, said main valve actuator assembly comprising a main valve pressure chamber,
a magnetic cup encompassing a rotary magnetic coupling containing at least one magnet
adjacent to a drive shaft wherein said magnetic cup is located within a pilot actuator
assembly, said pilot actuator assembly including a pilot orifice with a pilot valve,
a pilot flow shield, a bellows and an anti-rotation block such that passage of said
drilling fluid flows through a pilot flow screen and further flows into a main flow
entrance into a flow cone through a main orifice and into a main valve past the main
valve pressure chamber past a set of seals and through a main valve support block
toward a flow seal guide where said fluid combines with a pilot exit fluid that flows
toward a main exit flow such that as said fluid becomes a pilot fluid, said pilot
fluid subsequently flows through said pilot flow screen into said pilot flow screen
chamber through a pilot flow upper annulus, through a pilot flow lower annulus and
into a pilot flow inlet channel, wherein said pilot fluid then flows up into a main
valve feed channel until it reaches the main valve pressure chamber such that said
pilot fluid flows back down a main valve feed channel through a pilot flow exit channel
through said pilot orifice and said pilot valve such that said pilot fluid exits said
pilot valve and said pilot fluid then flows over said pilot flow shield such that
said pilot fluid combines with said main flow to become a main exit flow fluid, said
main exit flow fluid then exits a pilot valve support block and flows on either side
of said magnetic cup including said rotary magnetic coupling and wherein one or more
pressure sensors measuring the pressure of flowing fluid is located inside said pilot
valve support block upon which a helical pulser support rests wherein said pilot valve
support block also houses an annular pressure sensor residing in an annular pressure
inlet and wherein a lower portion of said pilot valve support block also contains
a helically cut cylinder that mates with and rests on the helical pulser support that
is mounted securely in a tubular hang-off collar such that said annular pressure inlet
is aligned with one or more collared annular pressure ports thus still allowing said
main exit flow fluid to flow past the drive shaft and motor such that said pilot fluid
and main exit flow fluid causes one or more flow throttling devices to generate large,
rapid controllable pulses thereby allowing transmission of well-developed signals
easily distinguished from any noise resulting from other vibrations due to nearby
equipment within said borehole or exterior to said borehole, or within said coiled
tubing assembly, wherein said signals also are capable of providing predetermined
height, width and shape.
6. The apparatus of claim 5, wherein a mating area for electrical wiring with said annular
pressure sensors exist for said collared annular pressure ports such that said ports
are sealed off by flow guide seals insuring that said annular pressure sensors receive
and sense only the annular pressure within said collared annular pressure ports.
7. The apparatus of claim 5 or 6, wherein electrical wiring of said annular pressure
sensors are sealed off from the flow of said main exit flow fluid with sensor cavity
plugs and wherein said wires are routed to an electrical connector.
8. The apparatus of one of claims 5 to 7, wherein said apparatus for generating pulses
includes a pilot, a pilot bellows, a flow throttling device, and a main valve pressure
chamber, such that said flow throttling device and said pilot are capable of bi-directional
axial movement without a guide pole.
9. The apparatus of one of claims 5 to 8, wherein a magnetic coupling is formed by a
location external and internal to said magnetic pressure cup where outer magnets are
placed in relation to inner magnets, said inner magnets located in a position inside
said magnetic pressure cup, said coupling allowing for translating rotational motion
of said motor and outer magnets to linear motion of said inner magnets via a magnetic
polar interaction, wherein linear motion of said inner magnets move said pilot actuator
assembly, thereby linearly moving a pilot into a pilot seat, closing a pilot seat
orifice, lifting a flow throttling device into a flow throttling orifice and thereby
generating a pulse wherein further rotation of said motor drive shaft, and outer magnets
move said pilot actuator assembly and said pilot away from said pilot seat causing
said flow throttling device to move away from said flow throttling orifice, thereby
ending a positive pulse.
10. The apparatus of one of claims 5 to 9, wherein said motor is connected to the drive
shaft through a mechanical device including mechanical means including a worm gear,
or barrel cam face cam for converting the rotational motion of said motor into linear
motion to propel said pilot actuator assembly, and / or wherein said apparatus includes
a path for said pilot and said flow throttling device for operation in a bi-directional
axial movement, and / or wherein said pilot actuator assembly is comprised of a rear
pilot shaft, front pilot shaft, pilot shield, and pilot.
11. The apparatus of one of claims 5 to 10, wherein differential pressure is maximized
with the use of said flow cone in that said cone provides for increasing the velocity
of said drilling fluid through said main valve actuator assembly, thereby greatly
enhancing the pressure differential and controllability of energy pulses created by
engagement or disengagement of said pilot valve from a pilot seat, and / or wherein
energy consumption is further reduced by pre-filling a bellows chamber with a lubricating
fluid, gel or paste.
12. The apparatus of one of claims 5 to 11, wherein said apparatus for generating pulses
includes allowing a bellows to move linearly, concurrent with said pilot actuator
assembly, wherein the design of said bellows interacts with said pilot actuator assembly
and a bellows chamber allowing said bellows to conform to the space constraints of
said bellows chamber providing flexible sealing without said bellows being displaced
by the pressure differential created by said drilling fluid.
13. The apparatus of one of claims 5 to 12, wherein said bellows may include a double
loop configuration designed for said flexible sealing thereby requiring less energy
consumption during displacement of said bellows,. and / or wherein said pulse in drilling
mud is sensed by instrumentation located uphole and wherein said pulse is communicated
with wireless devices, to a computer with a programmable controller for interpretation.
14. A method for generating pressure pulses in a drilling fluid flowing and enhancing
completion of a well bore within a coiled tubing assembly comprising: assembling and
utilizing a flow throttling device longitudinally and axially positioned within the
center of a main valve actuator assembly such that said main valve actuator assembly
comprises a main valve pressure chamber, a magnetic cup encompassing a rotary magnetic
coupling containing at least one magnet adjacent to a drive shaft wherein said magnetic
cup is located within a pilot actuator assembly and said pilot actuator assembly also
includes a pilot orifice with a pilot valve, a pilot flow shield, a bellows and an
anti-rotation block for allowing flow of said drilling fluid through a pilot flow
screen further allowing flowing into a main flow entrance into a flow cone through
a main orifice and into a main valve past the main valve pressure chamber past a set
of seals and through a main valve support block toward a flow seal guide where said
fluid combines with a pilot exit fluid that flows toward a main exit flow such that
as said fluid becomes a pilot fluid, said pilot fluid subsequently flowing through
said pilot flow screen into said pilot flow screen chamber through a pilot flow upper
annulus, through a pilot flow lower annulus and into a pilot flow inlet channel, wherein
said pilot fluid next is flowing up into a main valve feed channel until it reaches
the main valve pressure chamber such that said pilot fluid is subsequently flowing
back down the main valve feed channel through a pilot flow exit channel through said
pilot orifice and said pilot valve such that said pilot fluid exits said pilot valve
and said pilot fluid is subsequently flowing over said pilot flow shield to allow
for combining pilot fluid with said main flow to become the main exit flowing fluid,
said main exit flowing fluid next exits a pilot valve support block and continues
flowing on either side of said magnetic cup including said rotary magnetic coupling
and wherein one or more pressure sensors measuring the pressure of flowing fluid are
located inside said pilot valve support block upon which a helical pulser support
is resting and wherein said pilot valve support block is also housing an annular pressure
sensor residing in an annular pressure inlet and wherein a lower portion of said pilot
valve support block is also containing a helically cut cylinder for mating with and
resting on the helical pulser support mounted securely in a tubular hang-off collar
such that said annular pressure inlet is aligning with one or more collared annular
pressure ports thus still allowing said main exit flowing fluid to flow past the drive
shaft and motor such that said pilot fluid and main exit flowing fluid is causing
one or more flow throttling devices to generate large, rapid controllable pulses thereby
allowing transmission of well-developed signals easily distinguished from any noise
resulting from other vibrations due to nearby equipment within said borehole or exterior
to said borehole, or within said coiled tubing assembly, and wherein said signals
also are capable of providing predetermined height, width and shape.
15. Two or more apparatuses for generating pressure pulses in a drilling fluid flowing
within a coiled tubing assembly comprising: two or more flow throttling devices longitudinally
and axially positioned within the center of a main valve actuator assembly, said main
valve actuator assembly comprising a main valve pressure chamber, a magnetic cup encompassing
a rotary magnetic coupling containing at least one magnet adjacent to a drive shaft
wherein said magnetic cup is located within a pilot actuator assembly, said assembly
including a pilot orifice with a pilot valve, a pilot flow shield, a bellows and an
anti-rotation block such that passage of said drilling fluid flows through a pilot
flow screen and further flows into a main flow entrance into a flow cone through a
main orifice and into a main valve past the main valve pressure chamber past a set
of seals and through a main valve support block toward a flow seal guide where said
fluid combines with a pilot exit fluid that flows toward a main exit flow such that
as said fluid becomes a pilot fluid, said pilot fluid subsequently flows through said
pilot flow screen into said pilot flow screen chamber through a pilot flow upper annulus,
through a pilot flow lower annulus and into a pilot flow inlet channel, wherein said
pilot fluid then flows up into a main valve feed channel until it reaches said main
valve pressure chamber such that said pilot fluid flows back down the main valve feed
channel through a pilot flow exit channel through said pilot orifice and said pilot
valve such that said pilot fluid exits said pilot valve and said pilot fluid then
flows over said pilot flow shield such that said pilot fluid combines with said main
flow to become a main exit flow fluid, said main exit flow fluid then exits a pilot
valve support block and flows on either side of said magnetic cup including said rotary
magnetic coupling and wherein one or more pressure sensors measuring the pressure
of flowing fluid is located inside said pilot valve support block upon which a helical
pulser support rests wherein said pilot valve support block also houses an annular
pressure sensor residing in an annular pressure inlet and wherein a lower portion
of said pilot valve support block also contains a helically cut cylinder that mates
with and rests on the helical pulser support that is mounted securely in a tubular
hang-off collar such that said annular pressure inlet is aligned with one or more
collared annular pressure ports thus still allowing said main exit flow fluid to flow
past the drive shaft and motor such that said pilot fluid and main exit flow fluid
causes one or more flow throttling devices to generate large, rapid controllable pulses
thereby allowing transmission of well-developed signals easily distinguished from
any noise resulting from other vibrations due to nearby equipment within said borehole
or exterior to said borehole, or within said coiled tubing assembly, wherein said
signals also are capable of providing predetermined height, width and shape.