Modular axially stacked printed circuit board and heat sink assembly and well intervention tool component using the assembly

Abstract

A printed circuit board (PCB) assembly (25) has a PCB (16). A circumference of the PCB comprises a plurality of circumferentially spaced apart first protrusions (16A). Adjacent pairs of the first protrusions (16A) each define a notch (16B) therebetween. An upper heat sink (25C) comprises a ring (12) and a plurality of circumferentially spaced apart second protrusions (25A) on a perimeter of the ring (12). The second protrusions (25A) are longer than an axial dimension of the ring (12) wherein the second protrusions (25A) extend through respective notches (16B) on the PCB (16). A circular base plate (22) has third protrusions (22A) on a circumference thereof, wherein each of the third protrusions (22A) corresponds to one of the second protrusions (25A) when the base plate (22) and the PCB (16) are assembled to one axial side of the upper heat sink (25C).

Description

MODULAR AXIALLY STACKED PRINTED CIRCUIT BOARD AND HEAT SINK ASSEMBLY AND WELL INTERVENTION TOOL COMPONENT USING THE ASSEMBLYBACKGROUND

[0001] This disclosure relates to the field of well intervention tools. More specifically, the disclosure relates to structures for electronic circuit boards for use in such well intervention tools to enable the tools to operate at elevated temperatures for extended periods of time.

[0002] The term “well intervention tools” includes any instrument conveyed along the interior of a subsurface well for performing tasks related to, among others and without limitation, drilling, completion, remediation and abandonment of the well. Conveyance may be performed using, for example, deploying the tool at the end of an armored electrical cable, at the end of a coiled tubing, by drill pipe of completion pipe. In the case of conveyance by coiled tubing or drill pipe, the tool may be deployed during drilling the well.

[0003] Some well intervention tools comprise electronic circuitry in order to control and / or perform various functions of the tool, and / or to make measurements about the well and the earthen formations adjacent to the well. Those skilled in the art are aware that many wells, in particular very deep wells and / or wells used to recover geothermal energy expose the electronic circuits to high temperatures, and in the case of while-drilling tool operations, expose the circuits to high amplitude shock and vibration. Furthermore, while-drilling well intervention tools may be subjected to high temperature and shock for extended periods of time, e.g., several weeks.

[0004] It is known in the art to enclose electronic circuits in well intervention tools within a vacuum-insulated container (e.g., Dewar flask). Electronic circuit boards (“printed circuit boards” - PCBs) used in well intervention tools are typically rectangularly shaped, wherein mounting such circuit boards is principally designed to reduce mechanical resonance at particular frequencies so as to reduce mechanical failure of the PCBs inducedby motion of the intervention tool within a well, particularly in the case of while-drilling intervention tools. PCB arrangements known in the art, while making use of devices (heat sinks) to facilitate heat transfer away from components on the PCBs, may not be optimized for such heat transfer. Further, PCB structures known in the art may not provide separation between high power use devices (e.g., power transistors and related circuit drivers) that generate large amounts of heat and low power devices that do not generate large amounts of heat.

[0005] Accordingly, there is a need for improved circuit board structures for use with while-drilling well intervention tools, although the scope of the present disclosure is not limited to such tools.SUMMARY

[0006] One aspect of the present disclosure relates to a printed circuit board assembly. A printed circuit board (PCB) assembly according to this aspect of the disclosure has a PCB. A circumference of the PCB comprises a plurality of circumferentially spaced apart first protrusions. Adjacent pairs of the first protrusions each define a notch therebetween. An upper heat sink comprises a ring and a plurality of circumferentially spaced apart second protrusions on a perimeter of the ring. The second protrusions are longer than an axial dimension of the ring wherein the second protrusions extend through respective notches on the PCB. A circular base plate has third protrusions on a circumference thereof, wherein each of the third protrusions corresponds to one of the second protrusions when the base plate and the PCB are assembled to one axial side of the upper heat sink. The present aspect includes as an alternative that the third protrusions extend out of the plane of the base plate and engage corresponding notches in the PCB, wherein the second protrusions may not be longer than the axial dimension of the ring.

[0007] In another aspect, a PCB stack includes a plurality of PCB assemblies according to the above described aspect of the disclosure stacked end to end.

[0008] In another aspect, a well intervention tool comprises at least one PCB stack according to the above described aspect disposed in a pressure resistant housing having a housing adapter disposed at and sealingly engaging each end of the housing.

[0009] In some implementations of the well intervention tool, the housing is adapted to couple to a conveyance.

[0010] In some implementations of the well intervention tool, the conveyance comprises at least one of an armored electrical cable, coiled tubing, a drill pipe or a completion pipe.

[0011] In some implementations, at least one of the first protrusions comprises a connection for wiring to the PCB.

[0012] In some implementations, electrical wiring is connected to the connection on each of the PCBs in a PCB stack according to the present disclosure.

[0013] Some implementations further comprise a vibration damping ring disposed between at least one of the upper heat sink and the PCB, or the PCB and the base plate.

[0014] Some implementations further comprise a damping element disposed between the base plate and the PCB.

[0015] In some implementations, the upper heat sink is split axially, the assembly further comprising a heat transfer plate disposed between parts of the axially split upper heat sink, the heat transfer plate being in contact with at least one electronic component on a surface of the PCB.

[0016] A printed circuit board (PCB) assembly according to another aspect of the disclosure includes a PCB, an upper heat sink of a shape that matches a shape of the PCB, and is split axially. A heat transfer plate is disposed between the parts of the axially split upper heat sink. The heat transfer plate is in thermal contact with at least one electronic component on a surface of the PCB. A base plate has a shape that matches the PCB.

[0017] Some implementations further comprise a vibration damping element disposed between at least one of the upper heat sink and the PCB, or the PCB and the base plate.

[0018] Some implementations further comprise a damping element disposed between the base plate and the PCB.

[0019] Other aspects and possible advantages will be apparent from the description and claims that follow.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 shows an example implementation of a printed circuit board (PCB) assembly according to the present disclosure.

[0021] FIG. 1 A shows a plan view of an example implementation of a printed circuit board according to the present disclosure.

[0022] FIG. IB shows another exploded view of the PCB assembly of FIG. 1 to further illustrate certain features.

[0023] FIG. 1 C shows a cut away view of the PCB assembly of FIG. 1 to illustrate the arrangement of components of the completed assembly.

[0024] FIG. ID shows an oblique end view of an assembled PCB stack.

[0025] FIG. IE shows a sectional view of an example implementation of the PCB assembly having a split upper heat sink and heat transfer plate.

[0026] FIG. IF shows a cut away view of another example implementation of the heat transfer plate.

[0027] FIG. 2 shows an example printed circuit board (PCB) stack according to the present disclosure.

[0028] FIGS. 3A and 3B show various views of a well intervention tool part using one or more PCB stacks as shown in FIG. ID and FIG. 2.DETAILED DESCRIPTION

[0029] An example printed circuit board (PCB) assembly according to the present disclosure is shown in exploded view at 25 in FIG. 1. The PCB assembly 25 comprises anupper heat sink 25C, which may be made from high thermal conductivity metal such as aluminum or any other metal known in the art for use as electronic component or electronic circuit heat sinks. The upper heat sink 25C may be generally shaped as a ring 12, e.g., have a circular cross section, wherein the ring 12 has ribs, tabs or protrusions 25 A circumferentially spaced apart about the outer circumference of the ring 12 to define circumferential spaces 25B between adjacent protrusions 25 A (or a “pair” of protrusions 25 A). The protrusions 25 A may be longer than the axial thickness of the ring 12, such that the foregoing spaces 25B are defined beyond the axial thickness of the ring 12. “Upper” and “lower” in the present context refers to a possible axial orientation within a well intervention tool (explained further below) and not to any specific required position or orientation with respect to a fixed reference such as gravity.

[0030] A printed circuit board (PCB) 16 may be generally circular in shape and define circumferentially spaced apart notches 16B on its perimeter. The notches 16B generally correspond to the circumferential positions of the protrusions 25A on the upper heat sink 25C when the PCB assembly 25 is assembled. Thus, the PCB 16 may be disposed on one axial end of the ring 12, such that the notches 16B on the PCB 16 fit between the protrusions 25 A on the upper heat sink 25C. Correspondingly, the protrusions 16A on the PCB 16 are disposed within the spaces 25B defined by the protrusions 25 A on the upper heat sink 25C.

[0031] Referring to FIG. 1A, which shows a plan view of the PCB 16, a perimeter, shown at 16C, of the PCB 16, defined proximate the base of the notches 16B may be brought proximate to the axial end of the ring (12 in FIG. 1) on the upper heat sink (25C in FIG. 1). The foregoing perimeter 16C provides structural support to the PCB 16 when it is assembled to the ring (12 in FIG. 1).

[0032] Referring once again to FIG. 1, the PCB 16 and the ring 12 may be mechanically and electrically isolated from each other by a vibration damping ring 14, which may be made from an elastomer. The PCB 16 may be a conventional plastic resin PCB (“plastic PCB”), which may be made from polyimide or other plastic known in the art for use in PCBs. Low power consumption electronic components (not shown) such as integratedcircuits may be mounted on a plastic PCB (the PCB 16). The PCB 16 may also be a ceramic PCB using any ceramic materials known in the art for use in printed circuit boards. In some implementations, either a plastic PCB or ceramic PCB may be a metal core PCB, such as may comprise a core layer made from copper, aluminum or other high thermal conductivity metal to facilitate heat transfer from the PCB 16. Example implementations of metal core PCBs may be obtained from San Francisco Circuits, Inc., 1660 S Amphlett Blvd #200, San Mateo, CA 94402 among other suppliers. Ceramic PCBs may include a structural / insulating layer made from alumina or aluminum oxide (AI2O3), aluminum nitride (AIN), beryllia or beryllium oxide (BeO), silicon carbide (SiC), and boron nitride (BN), by way of example and without limitation. Example implementations of ceramic PCBs may be obtained from Millenium Circuits Limited, 7703 Derry St. Harrisburg, PA 17111. Ceramic and / or metal core PCBs may be used for attaching higher power generating components such as, for example and without limitation, silicon controlled rectifiers and power amplifiers. The type of electrical and / or electronic circuit components disposed on the PCB 16 is not intended to limit the scope of the present disclosure, nor is the material from which the PCB 16 is made.

[0033] A base plate 22, which serves the function of a bottom heat sink, may be disposed on a side of the PCB 16 opposed to the side of the PCB 16 placed proximate to the upper heat sink 25C. The base plate 22 may be made from aluminum or any other high thermal conductivity material such as those known to be used for electronic component or circuit heat sinks. The base plate 22 may be generally circularly shaped and may comprise on its exterior perimeter a plurality of circumferentially spaced apart protrusions 22A, which define, between adjacent protrusions 22 A, a plurality of circumferentially spaced apart spaces 22B. The protrusions 22A and spaces 22B on the base plate 22 correspond geometrically in size and shape to the protrusions 25A and spaces 25B on the heat sink 25C. The protrusions 22A may be axially coextensive with the thickness of the base plate 22 in some implementations.

[0034] A vibration damping ring 18, which may be made from an elastomer, may be disposed on the opposed side of the PCB 16 between the PCB 16 and the base plate 22. A damping element 20 made of thermally conductive, viscoelastic damping material may bedisposed between the opposed side of the PCB 16 and the face of the base plate 22 to provide mechanical support and electrical isolation between the PCB 16 and the base plate 22, as well as a thermally conductive path between the base plate 22 and the PCB 16. “Thermally conductive” for purposes of the present disclosure means thermal conductivity of at least 0.2 W / m-°K.

[0035] While the example implementation shown in FIG. 1 includes protrusions 25A on the upper heat sink 25C that extend beyond the axial end of the ring 12 to engage the notches 16B on the PCB 16, it is equally within the scope of the present disclosure to have the protrusions 22A on the base plate 22 extend axially out of the plane of the base plate 22 in order to engage the notches 16B on the PCB 16. In such implementations, the protrusions 25 A on the upper heat sink 25C may be axially coextensive with the ring 12.

[0036] Referring to FIG. IB, which shows another exploded view of the PCB assembly 25, the base plate 22 may further comprise a recess or dish 22C on the surface facing the damping element 20 to facilitate the damping element 20 being held in place laterally when the PCB assembly 25 is completed.

[0037] When the components shown in FIG. 1 are assembled axially, the PCB assembly 25 is formed. It will be appreciated that the protrusions 16A on the PCB 16 will be exposed through the spaces 25B, 22B, defined by the heat sink 25C and the base plate 22, respectively, and are thereby accessible. Use of such feature will be further explained with reference to FIG. 2. FIG. 1C shows a cut away view of the completed PCB assembly 25 wherein may be observed the relationship between the components described with reference to FIG. 1, and a heat flow path from the PCB 16 to the base plate 22.

[0038] For convenience in the description that follows, and with reference to FIG. 2, which is a partially exploded view, two or more of the PCB assemblies 25 arranged together in axial contact may be referred to as a “PCB stack” 10. The PCB stack 10 may form part of a well intervention tool part 50, examples of which will be explained in more detail with reference to FIGS. 3A and 3B.

[0039] The PCB stack 10 may comprise one or more axially extending guides 30 disposed over the protrusions 25 A on the heat sinks 25 C such that the individual PCB assemblies 25will remain in the same rotational orientation during further assembly of the PCB stack 10 to well intervention tool components. The PCB stack 10 may be disposed axially between an upper housing adapter 34 and a lower housing adapter 33. “Upper” and “lower” in the present context referring to a possible axial orientation within a well intervention tool (not shown) and not any specific required position or orientation with reference to the PCB stack 10. The adapters 34, 33 may engage, such as by threading, a pressure resistant housing (see FIG. 3B).

[0040] As explained with reference to FIG. 1 , the protrusions 16A on the PCB 16 may be exposed by being located within the spaces 25B, 22B in the heat sink 25C and base plate 22, respectively. Such feature enables attachment of electrical wiring 28, which may extend axially along the exterior of the individual PCBs 16 in the PCB stack 10. The wiring 28 may be used for either or both power and signal communication with the PCBs 16 in the PCB stack 10.

[0041] The PCB stack 10, after axial assembly of the PCB assemblies 25 and attachment of the wiring 28, may be disposed within a compression sleeve 32. The compression sleeve 32 may be in the form of a split annular cylinder to facilitate moving the compression sleeve 32 in its relaxed state over an axial end of the PCB stack 10. An end cap 36 may be disposed at one or both axial ends of the compression sleeve 32. To facilitate assembly of either of the adapters 33, 34, low friction washers 31 may be disposed between the end cap 36 and one or both of the adapters 33, 34. FIG. ID shows an oblique end view of the assembled PCB stack 10, guides 30, compression sleeve 32 and adapter 34. The compression sleeve 32 when radially compressed should make firm contact with the guides 30 that will also be forced to make firm contact with the protrusions 25A on the upper heat sink 25 C and the protrusions 22 A on the base plate 22 to facilitate heat transfer through the guides 30 and compression sleeve 32. Additionally, the compression sleeve 32 may protect the wiring 28 when it is mounted as shown in FIG. 2. Extending the wiring 28 over the exterior of the PCB assemblies 25 may facilitate repair of the wiring 28 and replacement of individual PCB assemblies 25 in the PCB stack 10 as may be needed from time to time.

[0042] FIG. IE shows a cut away view of another example implementation of a PCB assembly 27 according to the present disclosure. The structure of the present PCB assembly 27 may be similar to the structure of the PCB assembly shown in FIG. 1C. In FIG IE, certain high heat generating components shown, e.g., at 60 such as power amplifiers or silicon controlled rectifiers, may be mounted on one side of the PCB 16. A thermal pad 58 may be disposed on the components 60 to provide a thermally conductive path between the components 60 and a heat transfer plate 62. The heat transfer plate 62 may be made from any material known to be used in making electronic component or circuit heat sinks. In the present example implementation, the upper heat sink 25C may have similar geometry to the upper heat sink explained with reference to other implementations. The present upper heat sink 25C maybe split axially into a top upper heat sink 12A and a bottom upper heat sink 12B, wherein the heat transfer plate 62 is disposed between the top upper heat sink 12A and the bottom upper heat sink 12B such that there is a thermally conductive path between the components 60 and both parts of the split upper heat sink 25C.

[0043] In some implementations, and referring to FIG. IF, the thermal pad (58 in FIG. IE) may be omitted, and the heat transfer plate 62A may comprise stress relief features 63 such that when the heat transfer plate 63 is assembled, to the PCB assembly 27, the heat transfer plate 63 may deform slightly for direct thermal contact with the components (60 in FIG. IE) and have sufficient heat transfer capacity and mechanical strength to fill the foregoing purposes.

[0044] FIG. 3A shows a cross section transverse to the longitudinal axis, and FIG. 3B shows a corresponding cross section along the longitudinal axis L of an example implementation of part of a well intervention tool (“tool part”) 50 which may use one or more PCB stacks according to the present disclosure and as explained with reference to FIGS. 1 and 2. Some of the electronic components of the tool part 50, including the one or more PCB stacks 10 may be disposed inside an elongated, pressure resistant housing 52. The housing 52 may be generally cylindrically shaped and have pressure resistance capability to withstand the maximum fluid pressure expected in any well in which the intervention tool (not shown) is to be operated. The housing 52 may comprise at either or both axial ends an adapter 53, which enables mechanical and electrical connection toanother part of the well intervention tool (not shown) or to a conveyance such as armored electrical cable, slickline, coiled tubing or jointed tubing. One or more through passages 54 may provide places to disposed electrical wiring and / or fluid channels through the tool part 50, depending on the particular well intervention tool (not shown) and any other devices to which the tool part 50 may be connected. In the present example implementation, the PCB stack 10 may be mounted within the housing 52 such that the respective heat sinks 25C or when used the compression sleeve (see 32 in FIG. 2) fit tightly within the interior of the housing 52 to enable efficient heat transfer between the heat sinks (25C in FIG. 2) and the housing 52.

[0045] In the present example implementation, an insulated container (e.g., a vacuum insulated container such as a Dewar flask) 41 may be disposed within the housing 52. The insulated container 41 may comprise in its interior a PCB stack 10A made as explained with reference to FIGS. 1 and 2. An external diameter of the in-container PCB stack 10A is chosen to fit within the internal diameter of the insulated container 41. The thermally insulated container 41 may comprise within its interior other components for temperature control, for example and without limitation, one or more thermoelectric coolers 47, thermal regulator valves 42 and a heat sink 44, which may be made from suitable metal. A structural support 46 holds the thermally insulated container in place within the housing 52 on one axial end. The other axial end of the thermally insulated container 41 may comprise a thermally insulated plug 43, which thermally insulated plug may comprise an optical and / or electrical waveguide 45 for signal communication and / or electromagnetic induction couplings for communicating power and signals between circuits disposed on the PCB assemblies (25 in FIG. 1) and other devices outside the insulated container 41, e.g., circuitry on the PCB assemblies shown at 25 in FIG. 2.

[0046] Advantageously, a well tool part such as shown at 50 in FIG. 4B may form part of a well intervention tool wherein the well tool part 50 is disposed within a fluid channel inside the well intervention tool (not shown), e.g., a measurement while drilling (MWD) or logging while drilling (LWD) tool. In such tools, fluid pumped from surface through a central bore in the tool conveyance (e.g., drill pipe, coiled tubing, jointed tubing or the like) may act to remove heat from the tool part 50, wherein such heat is transferred to the housing52 and adapters 53. The arrangement of heat sink on the perimeter of each of the PCB(s) may optimize PCB cooling.

[0047] In light of the principles and example implementations described and illustrated herein, it will be recognized that the example implementations can be modified in arrangement and detail without departing from such principles. The foregoing discussion has focused on specific implementations, but other configurations are also contemplated. In particular, even though expressions such as in “an implementation," or the like are used herein, these phrases are meant to generally reference implementation possibilities, and are not intended to limit the disclosure to particular implementation configurations. As used herein, these terms may reference the same or different implementations that are combinable into other implementations. As a rule, any implementation referenced herein is freely combinable with any one or more of the other implementations referenced herein, and any number of features of different implementations are combinable with one another, unless indicated otherwise. Although only a few examples have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible within the scope of the described examples. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.

Claims

CLAIMSWhat is claimed is:

1. A printed circuit board (PCB) assembly, comprising: a PCB, a circumference of the PCB comprising a plurality of circumferentially spaced apart first protrusions, adjacent pairs of the first protrusions each defining a notch therebetween; an upper heat sink comprising a ring and a plurality of circumferentially spaced apart second protrusions on a perimeter of the ring; and a circular base plate having third protrusions on a circumference thereof, wherein each of the third protrusions corresponds to one of the second protrusions when the base plate and the PCB are assembled to one axial side of the upper heat sink, wherein either (i) the second protrusions are longer than an axial dimension of the ring or (ii) the third protrusions extend out of a plane of the base plate to engage respective notches on the PCB.

2. The assembly of claim 1 wherein at least one of the first protrusions comprises a connection for wiring to the PCB.

3. The assembly of claim 1 further comprising a vibration damping ring disposed between at least one of the upper heat sink and the PCB, or the PCB and the base plate.

4. The assembly of claim 1 further comprising a damping element disposed between the base plate and the PCB.

5. The assembly of claim 1 wherein the upper heat sink is split axially, the assembly further comprising a heat transfer plate disposed between parts of the axially split upper heat sink, the heat transfer plate being in thermal contact with at least one electronic component on a surface of the PCB.

6. A printed circuit board (PCB) stack, comprising: a plurality of PCB assemblies connected axially, each PCB assembly comprising a PCB, a circumference of the PCB comprising a plurality of circumferentially spaced apartfirst protrusions, adjacent pairs of the first protrusions each defining a notch therebetween, an upper heat sink comprising a ring and a plurality of circumferentially spaced apart second protrusions on a perimeter of the ring, the second protrusions longer than an axial dimension of the ring wherein the second protrusions extend through respective notches on the PCB; and a circular base plate having third protrusions on a circumference thereof, wherein each of the third protrusions corresponds to one of the second protrusions when the base plate and the PCB are assembled to one axial side of the upper heat sink, wherein either (i) the second protrusions are longer than an axial dimension of the ring or (ii) the third protrusions extend out of a plane of the base plate to engage respective notches on the PCB.

7. The stack of claim 6 wherein at least one of each of the first protrusions comprises a connection for wiring to the PCB.

8. The stack of claim 7 further comprising electrical wiring connected to some of the connections on each of the at least one first protrusions.

9. The stack of claim 6 further comprising a vibration damping ring disposed between at least one of each upper heat sink and each PCB, or each PCB and each base plate.

10. The stack of claim 6 further comprising a damping element disposed between each base plate and each PCB.

11. The stack of claim 6 wherein each upper heat sink is split axially, each PCB assembly further comprising a heat transfer plate disposed between parts of the axially split upper heat sink, the heat transfer plate being in thermal contact with at least one electronic component on a surface of the PCB.

12. The stack of claim 6 further comprising at least one guide disposed along an exterior of the second protrusions to hold the second protrusions in fixed rotational orientation.

13. A well intervention tool part comprising: at least one printed circuit board (PCB) stack the at least one PCB stack comprising a plurality of PCB assemblies connected axially, each PCB assembly comprising a PCB, a circumference of the PCB comprising a plurality of circumferentially spaced apart first protrusions, adjacent pairs of the first protrusions each defining a notch therebetween, an upper heat sink comprising a ring and a plurality of circumferentially spaced apart second protrusions on a perimeter of the ring; and a circular base plate having third protrusions on a circumference thereof, wherein each of the third protrusions corresponds to one of the second protrusions when the base plate and the PCB are assembled to one axial side of the upper heat sink, wherein either (i) the second protrusions are longer than an axial dimension of the ring or (ii) the third protrusions extend out of a plane of the base plate to engage respective notches on the PCB.; a housing adapter disposed at each axial end of the at least one PCB stack; and a pressure resistant housing, wherein the at least one PCB stack is disposed in the housing and wherein the housing adapter at each end of the housing sealingly engages a respective axial end of the housing.

14. The tool part of claim 13 wherein at least one of each of the first protrusions comprises a connection for wiring to the PCB.

15. The tool part of claim 14 further comprising electrical wiring connected to some of the connections on at least one of the at least one first protrusion.

16. The tool part of claim 13 further comprising a vibration damping ring disposed between at least one of each upper heat sink and each PCB, or each PCB and each base plate.

17. The tool part of claim 13 further comprising a damping element disposed between each base plate and each PCB.

18. The tool part of claim 13 wherein each upper heat sink is split axially, each PCB assembly further comprising a heat transfer plate disposed between parts of the axially split upperheat sink, the heat transfer plate being in thermal contact with at least one electronic component on a surface of the PCB.

19. The tool part of claim 13 further comprising at least one guide disposed along an exterior of the second protrusions to hold the second protrusions in fixed rotational orientation.

20. The tool part of claim 13 wherein the housing is adapted to couple to a conveyance.

21. The tool part of claim 20 wherein the conveyance comprises at least one of an armored electrical cable, coiled tubing, a drill pipe or a completion pipe.

22. A printed circuit board (PCB) assembly, comprising: a PCB; an upper heat sink of a shape that matches a shape of the PCB, the upper heat sink being split axially; a heat transfer plate disposed between the parts of the axially split upper heat sink, the heat transfer plate being in thermal contact with at least one electronic component on a surface of the PCB; and a base plate of shape that matches the PCB.

23. The assembly of claim 22 further comprising a vibration damping element disposed between at least one of the upper heat sink and the PCB, or the PCB and the base plate.

24. The assembly of claim 22 further comprising a damping element disposed between the base plate and the PCB.

25. A well intervention tool, comprising: a housing adapter disposed at each axial end of at least one PCB stack according to any of claims 6 through 12; and a pressure resistant housing, wherein the at least one PCB stack is disposed in the housing and wherein the housing adapter at each end of the housing sealingly engages a respective axial end of the housing.

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