US20120031669A1

US20120031669A1 - Memory Logging Drill Bit With Connectable Pulser

Info

Publication number: US20120031669A1
Application number: US12/852,334
Authority: US
Inventors: Ricardo Foster
Original assignee: GEARHART COS Inc
Current assignee: GEARHART COS Inc
Priority date: 2010-08-06
Filing date: 2010-08-06
Publication date: 2012-02-09

Abstract

The present invention discloses a novel drill bit system 100 having sealed chambers 330 located on the bit body 300. Batteries 350 and an electrical circuit board 352 are located in the chambers 330, including electronic data storage and sensors 354. An internal network of passages 332 connects the chambers 330. Data from the sensors 354 is stored on the data storage unit 352. A removable compact pulser 500 is locatable inside the bit body 300. The motor 522 of the pulser 500 is connectable to the circuit board 352 and batteries 350 through a portal 532 that passes through a centralizer fin 530 and aligns with an internal portal 334 connecting the interior of the bit body 300 to the interior of a sealed chamber 330. Drill bit 100 may be configured as a conventional drill bit, as a memory logging drill bit, or as an MWD drill bit.

Description

TECHNICAL FIELD OF INVENTION

The present invention relates to a new tool for use in subterranean exploration. In particular, the invention relates to a drill bit having an integral downhole data collection system having selectable on-board sensors and a centralized compact and removable pulser locatable internal to the drill bit. The new system has unique capabilities, functions and operations which are improvements over the known measurement-while-drilling (MWD) and logging-while-drilling (LWD) systems. The present invention provides rapid at the drill bit data collection and communication.

BACKGROUND OF THE INVENTION

In the exploration of oil, gas, and geothermal energy, drilling operations are used to create boreholes, or wells, in the earth. In many locations, the law requires creation of a log, or record, indicating the precise disposition of the descending wellbore. For vertical wellbores, inclination is usually the only required measurement of the path of the wellbore. It is also important to monitor the temperature of the well, which affects the calculation of the well angle data obtained from the onboard accelerometers.
Measurement-while-drilling (MWD) involves the evaluation of physical properties, such as pressure, temperature and wellbore trajectory in three-dimensional space, while extending a wellbore. The measurements are made downhole, stored in solid-state memory for a short time, and then transmitted to the surface. Data transmission usually involves digitally encoding data and transmitting the stored sensor measurements to the surface as pressure pulses in the mud system. The pressures may be positive, negative or continuous sine waves. Some MWD tools have the ability to store the measurements for later retrieval with wireline or when the tool is tripped out of the hole if the data transmission link fails.
For the purpose of optimizing the economics of the drilling operation, it is highly desirable to monitor numerous physical variables at the drill bit, including vibration and impact forces, torque, internal and external pressure, temperature, and other variables. Technological and economic barriers have prevented the development of an acceptable tool for measuring and recording this data at positions near to the bit. Likewise, there is no commercially available means for real time transmission of such data to the rig floor, where it could be used to optimize the parameters of the well being drilled and potentially avoid catastrophic failure of the drill bit and well.
Memory logging without real time transmission eliminates the need for an interface between data measurement and data transmission by sending sensor signals directly to memory storage. This eliminates processing and allows unlimited transfer and storage of large amounts of data which can be readily processed and analyzed when downloaded and as needed. Naturally, it would be even better to transmit this data to the surface in real time if the technology was available.
It is highly desirable to have down-hole measurements taken from a point nearest to the drill bit. This data is desirable for the purpose of obtaining a meaningful understanding or reconstruction of what happened during the drilling process. A principal disadvantage of conventional logging-while-drilling and measurement-while-drilling systems is that they must be mounted away from the drill bit. Conventional systems include actuators, a pulser, a motor, sensors, and battery systems which collectively comprise lengthy systems that are mounted on the surface side of the mud motor used to rotate the drill bit. This reduces the accuracy of the measurements taken and fails to provide near bit data for analysis. Also, it is necessary to locate the mud motor very close to the drill bit to prevent destruction and premature failure of the mud motor that results from high-speed rotation of longer and heavier drill string components below the mud motor.
Thus, it remains highly desirable to locate the sensors closer to the drill bit to provide data of greater value related to the forces acting on the bit itself. It is also highly desirable to provide an option for real-time communication of dynamic measurements of the drill bit such that indications of its wear and movement can be used to avoid catastrophic failure. It is also highly desirable to provide these capabilities
Prior art tool configurations that attempt to do this have failed to meet the economic and reliability requirements necessary to achieve commercial application. The harsh drilling environment, length and complexity of logging, and pulsing equipment have prevented efforts to accomplish this goal in the past. In particular, it has proven impractical to separate the drill bit from the mud motor by more than approximately 36 inches, and thus not possible to accommodate a lengthy MWD tool section below the mud motor.
Therefore, there is a need to develop an improved drill bit system which drills the well, takes measurements at the drill bit, records the measurements, and optionally sends real time data to the rig floor. There is a need for this system to be readily serviceable and highly compact, specifically, to have a length of approximately less than approximately 36 inches. There is also a need to develop a flexible system that can be configured to the requirements of the particular well being drilled. There is also a need to accomplish these goals at a reasonable cost.

SUMMARY OF THE INVENTION

The present invention provides a substantially improved and entirely unique drill bit system. In one embodiment of the present invention, the drill bit system is generally comprised of a bit head having a plurality of cutters attached to the bit head. A bit body having a hollow center extends upwards from the bit head. A threaded connection is located opposite to the bit head for connection to a drill string component. A plurality of sealed chambers is located in substantially symmetrical orientation on the bit body. At least one battery source is located in one of the chambers. Additional battery sources can be located in other chambers. An electrical circuit board is located in a chamber, and has an electronically connected data storage unit. Sensors are also located in one or more chambers. A chamber passage is provided for connecting adjacent chambers. A first electrical connection is located in the chamber passage for electrically connecting the battery source to the electrical circuit board.
In another embodiment, an interior portal is provided for connecting the hollow center of the drill bit to a chamber. A compact and removable pulser assembly is provided that is centrally positionable within the hollow center of the bit body. An electrical pulser connection electrically connects the pulser to the electrical circuit board and the battery source through an interior portal. In the embodiment, electrical signals from the circuit board actuate the pulser to generate momentary restrictions of the mud flow through the hollow center of the drill bit assembly.
In another embodiment, a second battery source is located in a chamber, and is electrically connected to the first battery source. In another embodiment, a third battery source is located in a chamber and is electrically connected to the first battery and second battery sources. The electrical connections pass through chamber passages to connect the first battery source, the second battery source, and the third battery source in electrical series connection.
In another embodiment, an external pressure transducer is mounted on an external surface of the drill bit body. An electrical connection is provided between the circuit board and the external pressure transducer. In this embodiment, electrical signals reflecting the pressure on the exterior of the drill bit are received by the circuit board, where they may be processed or recorded on the electronic data storage unit.
In another embodiment, an internal pressure transducer is mounted on the surface of the hollow interior of the drill bit body. An electrical connection is provided between the circuit board and the internal pressure transducer. In this embodiment, electrical signals reflecting the pressure on the hollow interior of the drill bit body are received by the circuit board, where they may be recorded on the electronic data storage unit.
In another embodiment, a download portal extends between the exterior of the bit body and a chamber. A download plug is located in the portal, and is electrically connected to the circuit board in a chamber. A sealed plug cover encloses the download portal and plug from the environment.
In another embodiment, the pulser has a flow diverter located on its upper end. A tubular centralizer body is attached to the diverter. Centralizer fins are positioned on the exterior of the centralizer body for centralizing the pulser within the hollow interior of the bit body. A motor is located inside the centralizer body. A hollow pulser plug is secured to the lower end of the centralizer body. A wheel housing is attached to the lower end of the pulser plug. A rotatable wheel is mounted on the lower end of the drive shaft, and is located inside the wheel housing.
A pulser portal is provided through the centralizer body and centralizer fins in alignment with the interior portal of the bit body. A feed-through pin extends through the interior portal and the pulser portal to provide a sealed passage for an electrical connection. An electrical pulser connection is positioned inside the feed-through pin, electrically connecting the motor to the electrical circuit board and the battery source.
A bolt portal is located inside a chamber. A fastener is located in the bolt portal and thread connected to the wheel housing to secure the pulser in place inside the drill bit.
Previous field tests have shown it is possible to acquire data that can help determine equivalent circulating density of the mud flow system and this or these sensors will also be a part of the memory data system that is stored for later study.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and features of the invention will become more readily understood from the following detailed description and appended claims when read in conjunction with the accompanying drawings in which like numerals represent like elements.

The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.

FIG. 1 is a side view of a prior art PDC drill bit.

FIG. 2 is an isometric view of the drill bit assembly of the present invention.

FIG. 3 is a cross-sectional view of the drill bit assembly of FIG. 2 illustrating the bit body chambers and network of passages between the chambers, and illustrating the portals between the chambers and the hollow interior of the drill bit.

FIG. 4 is an exploded view illustrating the primary electrical components present in the chambers and further illustrating the externally accessible download plug.

FIG. 5 is a side view of the compact pulser, made in accordance with the present invention.

FIG. 6 is a cross-sectional side view of the pulser of FIG. 5, illustrating the relationship of its component parts.

FIG. 7 is an exploded view of the preferred embodiment in which a compact, removable pulser is located internally within the drill bit.

FIG. 8 is an isometric cross-section illustrating the drill bit assembly shown with the pulser centralized inside the drill bit and connected to the electric components located in the chambers of the bit body.

FIG. 8A is a sectional view taken from FIG. 8 illustrating a feed through pin connecting the bit body and the pulser.

FIG. 8B is a sectional view taken from FIG. 8 illustrating fasteners securing the pulser inside the hollow interior of the drill bit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
FIG. 1 is a side view of a prior art PDC drill bit. As shown in this view, drill bit 10 has a hollow pin connection 20 on its upper end, a shank, or bit body 30 extending downward from pin 20, and a bit head 40 on the opposite end of body 30. A plurality of cutters 42 are positioned on bit head 40 for disintegration on formation. One or more nozzle outlets 404 (not shown) are located on bit head 40, providing an exit passage for drilling fluid from the interior of drill bit 10.
FIG. 2 is an isometric view of drill bit assembly 100 of the present invention. Drill bit 100 has a hollow pin connection 200 on its upper end, a bit body 300 extending downward from pin 200, and a bit head 400 on the opposite end of body 300. A plurality of cutters 402 are positioned on bit head 400 for disintegration on formation. One or more nozzle outlets 404 are located on bit head 400, providing an exit passage for drilling fluid from the interior of drill bit 100.
Pin 200 comprises a threaded pin 202 for connection to a drill string component, and a slot 204 for applying torque between the drill string and pin 202 for securing drill bit 100 to the drill string.
Body 300 of drill bit 100 has a hollow center 110 (illustrated in FIG. 3). A plurality of chamber covers 310 is removably secured to body 300. In another embodiment, a separate download plug cover 320 is removably secured to body 300.
FIG. 3 is cross-sectional view of the drill bit assembly 100 of FIG. 2 with chamber covers 310 and plug cover 320 removed and primary electrical components removed. Bit 100 has a hollow interior 110. A plurality of chambers 330 are formed on the exterior surface of bit body 300. In a preferred embodiment, chambers 330 are located in substantially symmetrical orientation on bit body 300. Chamber passages 332 connect adjacent chambers to form an interconnected subsurface network beneath the exterior surface of bit body 300.
In a preferred embodiment, a plurality of interior portals 334 are located in chambers 330 and intersect hollow interior 110 of drill bit 100. In a more preferred embodiment, interior portals 334 are generally cylindrical and have a centerline approximately intersecting the centerline of hollow interior 110.
In another preferred embodiment, a download port 340 is located beneath the exterior surface of bit body 300. Download port 340 is covered and sealed from the external environment by port cover 320 (FIG. 2). A download channel 336 extends between download port 340 and one of sealed chambers 330.
FIG. 4 is an exploded view of the embodiment disclosed in FIG. 2, illustrating the primary electrical components present in chambers 330 and further illustrating the externally accessible download plug 342. Batteries 350 are located in sealed chambers 330. A circuit board 352 having an associated memory storage unit is also located in a sealed chamber 330. One or more sensors 354 are also located in a sealed chamber 330 and are electrically connected to circuit board 352.
Electrical connections 360 (not shown) are located in chamber passages 332 electrically connecting batteries 350 to electrical circuit board 352. A download plug 342 is located in download port 340, and is accessible upon removal of plug cover 320. Download plug 342 is electrically connected to circuit board 352 by wiring (not shown) located in download channel 336 (FIG. 3).
In another preferred embodiment (not illustrated), an external portal is provided. An external pressure transducer is surface mounted on the external surface of drill bit body 300. An electrical connection is provided between external pressure transducer and circuit board 352.
In another preferred embodiment (not illustrated), an internal pressure transducer is mounted in an interior portal 334, exposed to the fluid flow inside hollow interior 110 of drill bit body 300. An electrical connection is provided between internal pressure transducer and circuit board 352.
FIG. 5 is a side view of a compact, removable pulser 500 made in accordance with the present invention. Pulser 500 has a conical flow diverter 510 on its upper end. A hollow centralizer body 520 is located beneath diverter 510. A plurality of centralizer fins 530 is located on centralizer body 520. A body plug 540 is attached to the lower end of centralizer body 520. A wheel assembly 550 is attached to the lower end of body plug 540.
FIG. 6 is a cross-sectional side view of pulser 500 of FIG. 5, illustrating the relationship of its component parts. As shown in this view, a motor 522 is located inside hollow centralizer body 520. A motor shaft 524 extends from the lower end of motor 522. In a preferred embodiment, a flexible drive connector 526, such as an Oldham connector, is connected to motor shaft 524. In another preferred embodiment, flexible connector 526 is positioned in a holder 528.
The upper end of plug 540 is located inside hollow centralizer body 520. The lower end of plug 540 extends below centralizer body 520.
Plug 540 has a hollow bore 542. A drive shaft 544 is located in bore 542. The upper end of drive shaft 544 is connected to motor 522 through flexible connector 526 such that rotation of motor 522 rotates drive shaft 544.
Wheel assembly 550 includes a ventilated wheel housing 552. A plurality of bolt receiving holes 554 is located on the outer diameter of wheel housing 552. A rotatable wheel 556 is positioned inside wheel housing 552.
A bearing end cap 558 secures wheel 556 inside wheel assembly 550. Drive shaft 544 is attached at its lower end to wheel 556 by a drive shaft nut 548, such that rotation of drive shaft 544 rotates wheel 556. As best seen in FIG. 6, a plurality of wheel passages 562 extend through wheel 556 for selective alignment with complementary housing passages 564 in wheel housing 552.
Referring again to FIG. 6, a pulser portal 532 extends through centralizer fin 530 and through hollow centralizer body 520. In the preferred embodiment, a centralizer tube 534 is located in pulser portal 532.
FIG. 7 is an exploded view of the preferred embodiment in which compact, removable pulser 500 is located inside hollow interior 110 of drill bit 100. When so positioned, pulser 500 is axially aligned such that receiving holes 554 are in alignment with lower interior portals 334 (see FIG. 3) nearest bit head 400, and pulser portal 532 is in alignment with an upper interior portal 334 (FIG. 3).
FIG. 8 is an isometric cross-section of pulser 500 centralized in hollow interior 110 of drill bit 100. Pulser 500 is axially aligned such that receiving holes 554 are in alignment with lower interior portals 334. Fasteners 600 are located in interior portals 334 to attach wheel assembly 550 to drill bit body 300. A feed through pin 610 is located in upper interior portal 334 aligned with pulser portal 532 to provide a sealed passageway through which an electrical motor connection 612 can pass for connection of motor 522 to circuit board 352.
FIG. 8A is a sectional view taken from FIG. 8 illustrating feed through pin 610 located in upper interior portal 334 to provide a sealed passage for electrical connection between batteries 350, circuit board 352 and motor 522.
FIG. 8B is a sectional view taken from FIG. 8 illustrating fasteners 600 located in lower interior portals 334 and secured to bolt receiving holes 554 on wheel housing 552, thus securing pulser 500 inside hollow interior 110 of drill bit 100. Referring back to FIG. 8, centralizer fins 530 centralize the upper portion of pulser 500 inside hollow interior 110 of drill bit 100.

OPERATION OF THE INVENTION

The present invention provides a substantially improved drill bit system in which drill bit 100 may be optionally configured as a conventional drill bit, as a memory logging drill bit, or as an MWD drill bit including a novel compact and removable pulser 500. In one embodiment of the present invention, drill bit 100 is generally comprised of a bit head 400 having a plurality of cutters 402 attached for disintegration of the formation. Bit body 300 has a hollow center 110 extending upwards from bit head 400.
A conventional threaded pin connection 200 is located opposite to bit head 400 for connection to a drill string component. Sealed chambers 330 are located in substantially symmetrical orientation on bit body 300. Interior portals 334 extend from chambers 300 to hollow interior 110 of drill bit 100. In one embodiment, interior portals 334 may be plugged, such as with threaded fasteners 600, or plugs attached by other means. In this embodiment, drill bit 100 functions in a manner similar to that of prior art PDC drill bit 10 (see FIG. 1).
In a more preferred embodiment, drill bit 100 is configured for memory logging. Referring to FIG. 4, in this embodiment, at least one battery source 350 is located in one of the chambers 330. Additional battery sources can be located in other chambers 330. One or more electrical circuit boards 352 are located in another chamber 330. Circuit board 352 has an electronic data storage unit and sensors 354. Sensors 354 may be of various types well known in the oil and gas industry, and may typically include accelerometers. Cover plates 310 protect the contents of chambers 330 from the drilling fluid and cuttings.
Chamber passages 332 form a network of subsurface passages 332 between chambers 330 through which electrical connections 360 (not shown) are located to facilitate electrical connection between the batteries 350, circuit boards 352 and sensors 354 in a manner protected from the drilling fluid environment.
In a preferred embodiment, download port 340 is provided. Download plug 342 is located in download port 340 and covered by download plug cover 320 for protection from the drilling fluid during drilling operations. Download passage 336 connects download port 340 to a chamber 330 where circuit board and data storage unit 352 are located. Electrical wiring in download passage 336 connects download plug 342 to circuit board and data storage unit 352.
As drilling progresses, sensors 354 provide data to circuit board and data storage unit 352. When drill bit 100 is brought to the surface, download plug cover 320 can be removed for access to download plug 342. This permits rapid download of the data stored on circuit board and data storage unit 352. The immediate access to the data can be used to change operating parameters on the drilling rig, change the drilling bit, make adjustments to the drill string configuration, or used in other decisions for the optimization of the drilling operation. Additionally, download plug 342 can be configured to permit charging of batteries 350. As generally described above, drill bit 100 is configured as a memory logging drill bit 100 with sensors 354 located advantageously near to drill bit head 400.
In another embodiment, an external pressure transducer (not illustrated) is mounted on an external surface of drill bit body 300. An electrical connection is provided between circuit board 352 and the external pressure transducer. In this embodiment, electrical signals reflecting the pressure on the exterior of drill bit 100 are processed and/or recorded on the electronic data storage unit of circuit board 352.
In another embodiment, an internal pressure transducer (not illustrated) is mounted on the surface of hollow center 110 of drill bit body 300. An electrical connection is provided between circuit board 352 and the internal pressure transducer. In this embodiment, electrical signals reflecting the pressure on the interior of drill bit 100 are processed and/or recorded on the electronic data storage unit of circuit board 352.
In another embodiment, drill bit 100 is configured as an MWD drill bit capable of sending real time data to the surface of the rig by means of mud pulses sent through a compact and removable pulser 500. Unlike conventional MWD tools, in the present invention, the power source (batteries 350) and electronics (circuit board and data storage unit 352 and sensors 354) are located generally concentrically around pulser 500. By electrically connecting to the electronics (350, 354, 352, 360) built integrally into drill bit body 300 for memory logging through alignment of pulser portal 532 located in centralizing fin 530 with internal portal 334, an extremely compact MWD drill bit can be made to provide real time data transmission from sensors 354 located advantageously near to drill bit head 400.
In this embodiment, drill bit 100 is configured substantially the same as the memory logging bit described above, except in that interior portals 334 are not plugged. Referring to FIG. 8, compact pulser 500 is positioned inside hollow center 110 of drill bit 100. Centralized fins 530 centralize pulser 500 in hollow center 110. Pulser 500 is rotated until pulser portal 532 is in axial alignment with an interior portal 334. At this point of alignment, bolt receiving holes 554 on wheel housing 552 are also in alignment with other interior portals 334.
Fasteners 600 are placed through interior portals 334 and secured to bolt receiving holes 554 on wheel housing 552. This holds pulser 500 in place inside hollow center 110 of drill bit 100. In a preferred embodiment, a centralizer tube 534 is located inside pulser portal 532, and a feed through pin 610 extends through interior portal 532 and centralizer tube 534. An electrical connection 360 (not shown) is located inside feed through pin 610 to electrically connect motor 522 of pulser 500 with batteries 350 and circuit board and data storage unit 352.
Chamber passages 332 form a network of subsurface passages 332 between chambers 330 through which electrical connections 360 (not shown) are located to facilitate electrical connection between the batteries 350, circuit boards 352 and sensors 354 in a manner protected from the drilling fluid environment.
As drilling fluid is pumped down the interior of the drill string, it reaches hollow center 110 of drill bit body 300, and flow diverter 510. Flow diverter 510 reduces the pressure loss caused by the impingement of high speed fluid flow on pulser 500. As drilling progresses, sensors 354 provide data to circuit board and data storage unit 352. Circuit board and data storage unit 352 process the sensor signal and send an output signal to motor 522. Referring to FIG. 6, the output signal activates rotation of motor 522, which rotates drive shaft 544 and thus rotatable wheel 556.
Rotation of wheel 556 moves wheel passages 562 and wheel housing passages 564 out of alignment, thus generating a momentary restriction of the mud flow through hollow center 110 of drill bit 100. This restriction results in a system pressure spike that is detectable at the rig surface. The pulses detected at the rig surface communicate to rig personnel the data provided by sensors 354.
Real time access to data generated proximate to drill bit head 400 can be used to change operating parameters on the drilling rig while drilling, or used to make a decision to remove the drill bit entirely. When drill bit 100 is brought to the surface, pulser 500 can be retained or removed. If pulser 500 fails for any reason, data stored on circuit board and data storage unit 352 can be downloaded through download plug 342, and a new pulser 500 can be placed in hollow center 110 of drill bit body 300.
As cutters 402 on drill bit 100 wear down, pulser 500 and electrical components such as batteries 350, circuit board 352 and sensors 354 can be removed and installed inside a new drill bit 100.
In the manner described above, drill bit assembly 100 can be manufactured and assembled to include pulser 500 such that the overall length is sufficiently short to permit real-time data transmission from below a mud motor. For example, an 8½ inch drill bit assembly 100 can be manufactured, including the internal assembly of pulser 500, to have a length of 36 inches or less. For example, an 8¾ inch drill bit assembly 100 can have an overall length, including bit head 400, pulser 500 and threaded pin 202, of less than 30 inches.
It will be readily apparent to those skilled in the art that the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention.
Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.

Claims

1. A drill bit, comprising:

a bit head;

a plurality of cutters attached to the bit head;

a bit body having a hollow center, extending upwards from the bit head;

a threaded connection located opposite to the bit head for connection to a drill string component;

a plurality of sealed chambers located in substantially symmetrical orientation on the bit body;

a battery source located in a chamber;

an electrical circuit board located in a chamber, and including an electronic data storage unit;

a sensor located in a chamber;

a chamber passage connecting adjacent chambers; and,

a first electrical connection in the chamber passage electrically connecting the battery source to the electrical circuit board and sensors.

2. The drill bit assembly of claim 1, further comprising:

an interior portal connecting the hollow center to a chamber;

a removable pulser assembly positionable within the hollow center of the bit body;

a pulser portal located in alignment with the interior portal;

an electrical connection extending through the interior portal and the pulser portal and electrically connecting the pulser to the electrical circuit board and the battery source; and,

wherein electrical signals from the circuit board actuate the pulser to generate momentary restrictions of the mud flow through the hollow center of the drill bit assembly.

3. The drill bit assembly of claim 1, further comprising:

a second battery source located in a chamber;

a third battery source located in a chamber; and,

a series electrical connection passing through chamber passages to connect the first battery source, the second battery source, and the third battery source in electrical series connection.

4. The drill bit assembly of claim 1, further comprising:

an external pressure transducer mounted on an external surface of the drill bit body; and

an electrical connection between the circuit board and the external pressure transducer.

5. The drill bit assembly of claim 1, further comprising:

an internal pressure transducer mounted on the surface of the hollow interior of the drill bit body; and

an electrical connection between the circuit board and the internal pressure transducer.

6. The drill bit assembly of claim 1, further comprising:

a download portal extending between an exterior surface of the drill bit body and the sealed chamber having the circuit board;

a download plug located in the portal;

an electrical connection between the download plug and the circuit board;

a removable plug cover covering the download portal; and,

wherein upon removal of the plug cover, data located on the electronic data storage unit may be downloaded through the download plug.

7. The drill bit assembly of claim 2, the pulser further comprising:

a flow diverter located on an upper end of the pulser;

a centralizer located on the exterior of the pulser;

a motor located internally;

a rotatable wheel located in a wheel housing on a lower end of the pulser;

a drive shaft connecting the motor to the wheel;

a centralizer tube extending between the centralizer and the interior portal of the bit body; and,

wherein the electrical pulser connection passes through the centralizer tube for electrically connecting the pulser to the electrical circuit board and the battery source.

8. The drill bit assembly of claim 1, further comprising:

the length of the drill bit assembly being less than 36 inches.

9. A drill bit, comprising:

a bit head;

a plurality of cutters attached to the bit head;

a bit body having a hollow center, extending upwards from the bit head;

a battery source located in a chamber;

a sensor located in a chamber;

a chamber passage connecting adjacent chambers;

a first electrical connection in the chamber passage electrically connecting the battery source to the electrical circuit board and sensors;

an interior portal connecting the hollow center to a chamber;

a pulser assembly located in the hollow center of the bit body;

a pulser portal located in alignment with the interior portal;

10. A removable pulser for location in the hollow center of a drill bit having a power source and electrical components, comprising:

a flow diverter located on an upper end of the pulser;

a centralizer located on the exterior of the pulser;

a motor located internally;

a rotatable wheel located in a wheel housing on a lower end of the pulser;

a drive shaft connecting the motor to the wheel;

an electrical pulser connection extending from the pulser to an interior portal located in the hollow center of the drill bit body; and,

the electrical pulser connection electrically connecting the motor of the pulser to a power source in the drill bit.

11. The drill bit assembly of claim 10, the pulser further comprising:

a centralizer tube extending between the centralizer and the interior portal of the drill bit body; and,

the electrical pulser connection located inside the centralizer tube.