WO2021186419A1

WO2021186419A1 - Shock tool

Info

Publication number: WO2021186419A1
Application number: PCT/IB2021/052347
Authority: WO
Inventors: Jonathan Prill
Original assignee: Bico Faster Drilling Tools Inc.
Priority date: 2020-03-20
Filing date: 2021-03-21
Publication date: 2021-09-23

Abstract

A shock tool for a drill string includes an inner tubular assembly having a connector at a first end for coupling to the drill string. An outer tubular housing having a connector at a second end for coupling to the drill string. A second end of the inner tubular assembly telescopically received within the bore of the outer tubular housing. A spring assembly disposed between the first end of the inner tubular assembly and the second end of the outer tubular housing. A sealed internal fluid chamber to contain a lubricating fluid. The fluid chamber is linked to internal fluid passageways to allow flow of lubricating fluid within the tool, and a piston to isolate the internal fluid chamber from drilling fluid.

Description

SHOCK TOOL

BACKGROUND

[0001] In drilling a wellbore into the earth, such as in exploration and recovery of hydrocarbons, a drill bit is connected on the lower end of an assembly of drill pipe sections connected end-to-end to form a “drill string”. The upper end of the drill string isoperatively connected to a drilling apparatus at surface (for example, drill head, rotary head, or double-head system) that rotates the drill string causing the bit to penetrate subsurface formations down to hydrocarbon-bearing strata and in the process excavating formation materials for removal up to surface.

[0002] During wellbore drilling operations, varying physical characteristics and conditions of the subsurface materials being penetrated can cause fluctuations in the stresses and forces transmitted up the drill string to the drilling apparatus. These fluctuating stresses may include vibration and shock impulses that cause the drill bit to “hop”, which in turn can cause the drill bit to cut slowly or unevenly through theformation. As well, the vibration and shock impulses can cause unexpected mechanical wear to components of the drilling system, potentially causing or contributing to failure to of such components. These and other problems related to fluctuating drill stringstresses and forces can increase the duration and cost of drilling operations.

[0003] Validation and acceptance of innovative downhole equipment in the drilling industry can be challenging, particularly because conventional drilling tools are essentially mechanical in nature and typically cannot transmit information to the surface that would provide a comprehensive and reliable understanding of the drilling conditions far below the surface, and that would provide meaningful tool performance data and thus inform best drilling practices. This lack of real-time information regarding actual downhole conditions can make it difficult to assess the performance of downhole tools, leading to or contributing to unexpected failures and unreliable field test results, all of which can inhibit the development and implementation of innovative technologies for the drilling industry.

[0004] For these reasons, the incorporation of electronic data-collecting devices into drill strings has become an increasing common practice in the drilling industry. However, such data- collecting devices tend to be comparatively delicate and sensitive, and therefore are prone to damage when subjected to vibration and shock impulses that commonly occur during normal drilling operations. Additionally, some common drilling practices either intentionally or incidentally induce shock impulses throughout the drill string, such as:

• agitators that induce vibration or a hammering effect to keep the drill string in adynamic state of friction in order to prevent “sticking” of the drill string in the wellbore;

• the use of downhole motors (also called “mud motors”) incorporated into the drill string to rotate the “bottom hole assembly” (or “BHA”, as defined later herein) atspeeds beyond the capability of the drilling apparatus at surface;

• the use of “jar” tools to apply shock load to the drill string in order to dislodge stuck sections of drill pipe or other drill string components; and

• perforation guns that fracture formation materials surrounding the drill string by means of controlled explosions during well completion operations, to facilitate the flow of hydrocarbon fluids from subsurface formations into the wellbore.

[0005] Shock absorbers (also called “shock tools”) can be used to reduce the risk of damage to sensitive components such as (but not limited to) data-collecting electronic devices incorporated into drill strings due to vibrations and shock impulses resulting fromthese and other drilling-related practices. A shock tool is a component incorporated into a lower region of a drill string to damp or absorb vibrations and shock impulses created during drilling operations that could damage the drilling apparatus or other parts of the drilling system, including drill string components.

[0006] A typical shock tool comprises an outer tubular tool housing, the lower end of which is connected to the BHA, plus an inner tubular component, the upper end of which is connected to the drill string above the shock tool, such that the inner tubular component is coaxially movable within and relative to the tool housing. Shock impulses (i.e., sudden or abrupt axial accelerations) applied to or induced in the drill string below the shock tool are at least partially damped or absorbed by the shock tool so that drill string components above the shock tool are not subjected to the full magnitude of the applied shock impulse loads.

[0007] A shock impulse applied at the bottom end of the shock tool causes the tool housing to accelerate rapidly upward so as to transmit the force of the shock impulse through the shock tool and into a spring system. The spring system compresses and absorbs the shock impulse so that the inner tubular assembly transmits the resultant damped force from the other end of the spring system and upward into the drill string above the shock tool. Because shock impulses of greater or lesser magnitudes are constantly being generated during drilling operations as a result of many drilling-related processes, the shock tool housing (and the BHA and the drill bit along with it) continually oscillates longitudinally to absorb sudden accelerations and resultant shock impulses produced during drilling operations.

BRIEF DESCRIPTION OF THE DRAWINGS [0008] Embodiments will now be described with reference to the accompanying Figures, in which numerical references denote like parts, and in which:

[0009] FIGURE 1 illustrates, in isometric side view and partial cutaway view, the general assembly of an exemplary embodiment 100 of a shock tool in accordance with the present disclosure, comprising a spline section 200, aspring section 300, and a sealing section 400. [0010] FIGURE 2 includes an isometric side view of spline section 200 of shock tool 100, comprising a spline mandrel 211, a spline housing 221, a spline seal housing 222, and a pressure seal housing 223, plus enlarged isometric and sectional views of spline mandrel 211 and spline housing 221.

[0011] FIGURE 3 includes multiple isometric partial cutaway views of spring section 300 of shock tool 100, comprising an outer spring assembly 310 and an inner spring assembly 320. Spring mandrel 321 is threadingly coupled to spline mandrel 211, and spring housing 311 is coupled to spline housing 221 (not shown in FIG. 3).

[0012] FIGURE 4 includes further isometric views of components and features of spring section 300, including flow channels and radial flow ports machined into lower spring wear ring 322 and spring mandrel 321.

[0013] FIGURE 5A is an isometric partial cutaway view of spring section 300 as seen under normal drilling loads. End point 103 of the inner tubular components is shown in the bottom sub 102 for reference. The outer tubular assembly’s axial position relative to the fixed inner tubular assembly does not change significantly during normal drilling operations.

[0014] FIGURE 5B is an isometric partial cutaway view of spring section 300 as seen when compressing under dynamic loading. End point 103 of the inner tubular components is shown in the bottom sub 102 for reference. The outer tubular assembly’s axial position relative to the fixed inner tubular assembly change significantly during a shock load occurrence.

[0015] FIGURE 6 details sealing mechanisms on the upper and lower ends of the oil chamber 101 of shock tool 100. The upper end of oil chamber 101 is sealed by a grease seal created by filling grease chamber 218 with grease. The lower end of oil chamber 101 is sealed by a balance piston 401 on the shock tool’s inner tubular assembly, creating a high-pressure seal and allowing the oil in oil chamber 101 to expand when heated to downhole temperatures. FIG. 6 also includes an isometric partial cutaway of the complete shock tool 100.

TERMINOLOGY AND INTERPRETATION [0016] As persons skilled in the art will appreciate, different drilling equipment manufacturers may refer to a given equipment component by different names. The present disclosure does not intend to distinguish between components that differ in name but not in function. However, for purposes of this disclosure, certain terms used herein are intended to be understood in accordance with the following specific meanings:

[0017] “Drill String” means the assembly of tubular components connecting a drill bit to surface equipment (e.g., a drilling rig).

[0018] “Drill Pipe” means the assembly of tubular components in the drill string that connect the surface equipment to the drill bit. The bore of drill pipe providesa conduit for the flow of drilling fluid (“drilling mud”) under pressure from surface to the drill bit, to facilitate cutting and cleaning of subsurface materials through which the drill bit progresses in the process of creating a wellbore, with the drilling fluid being circulate back up to surface via the annulus between the drill pipe and the wellbore.

[0019] “BHA” or “Bottom Hole Assembly” means an assembly of selected tools and tubular components coupled to the bottom of the drill pipe in the drill string. The BHA includes the drill bit, but it does not include the drill pipe.

[0020] Any reference herein to the “upper” end of a drill string or any component thereof is to be understood as denoting the end that is closer to the ground surface than to the drill bit along the path of the string, and, any reference to the “lower” end of a drill string or any component thereof denotes the end that is closer to the drill bit than to the ground surface along the path of the string, irrespective of the actual angular orientation of the string or particular component in question. Similarly, the adjectives “upward” and “downward” are to be interpreted as meaning “toward the upper lower end” or “toward the lower end” (as the case may be) of the element in question. DESCRIPTION

[0021] The Figures illustrate an exemplary embodiment 100 of a shock tool in accordance with the present disclosure. Shock tool 100 includes two main components, namely:

• an elongate tubular tool housing (which may be formed from multiple tubular sections threaded together); and

• an tubular inner assembly coaxially disposed wi thing the bore of the tool housing, and comprising an elongate mandrel assembly having multiple coaxial mandrel elements that are serially connected (such as by threaded connections).

[0022] The tool housing isolates the inner workings of the shock tool (which include the mandrel assembly) from circulating drilling mud. For enhanced clarity for purposes of this disclosure, the inner tubular assembly and the outer tubular assembly are discussed with reference to constituent sections or subassemblies thereof, with each section or subassembly being named, for convenience, with reference to a distinctive feature or general function of the section or subassembly.

[0023] In the illustrated embodiment, shock tool 100 defines a generally annular oil chamber 101 defined in part by machined passageways including radial holes, grooves, and slots configured to lubricate the tool’s internal moving components and to facilitate the flow of oil within oil chamber 101 during drilling operations. As illustrated in FIG. 1, shock tool 100 comprises three subassemblies, namely (in sequence from the upper end of the tool toward the lower end), a spline section 200 including a spline mandrel 211 and a spline housing 221; a spring section 300; and a sealing section 400.

[0024] As may be understood with reference to FIG. 2, shock tool 100 is configured to be coupled to the lower end of a drill string via spline mandrel 211 on the upper end of a spline inner assembly 210. Spline housing 221 defines longitudinal internal spline ridge cuts that are matingly engageable with external angled spline ridge protrusions on spline mandrel 211 to establish a connection that can transfer torque between spline mandrel 211 and spline housing 221 while maintaining relative axial movability within the axial(i.e., longitudinal) limits of the spline ridges. [0025] The angled cuts on the external spline ridge protrusions on spline mandrel 211 can be of any configuration that allows spline mandrel 211 ridge protrusions to transfer torque throughout drilling operations, while preferably also creating gaps or passages facilitating the flow of lubricating fluid or oil throughout the splined connection. As shown in the sectional view of the spline mandrel 211 and spline housing 221 in FIG. 2, one or more of the spline ridge protrusions 225 on the spline mandrel 211 is configured with an angled surface 226 to provide an axial oil flow channel 227 when the spline ridge protrusion is matingly engaged with a spline ridge cut 228 in the spline housing.

[0026] A spline seal housing 222 is coaxially coupled to spline housing 221 (such as by a threaded connection), and includes a wear ring 213 that acts as a sacrificial element intended to wear or degrade before spine mandrel 211 and spline seal housing 222, thus preserving the integrity of spine mandrel 211 and spline seal housing 222, which are subjected to significant radial and axial forces as they slide telescopically across spline mandrel 211 (along with pressure seal housing 223).

[0027] As shown in FIG. 3, spring section 300 of shock tool 100 includes a disc spring stack 323. The full length of spring section 300 is shown with its upper and lower ends enlarged for clarity. Spring section 300 comprises an inner spring assembly 320 and an outer spring assembly 310. Inner spring assembly 310 comprises a spring mandrel 321, an upper spring wear ring 322, a plurality of disc springs (making up disc spring stack 323), and a lower spring wear ring 324. Spring mandrel 321 is coupled to spline mandrel 211. In operation, the disc spring stack 323 compresses when the tool 100 is in tension and compression. The upper, outer spring seat (affixed to the housing 311) and lower inner spring seat (affixed to the mandrel 321) compress the spring stack when the tool is in tension. The upper, inner spring seat (affixed to the mandrel 321) and lower outer spring seat (affixed to the housing 311) compress the spring stack 323 when the tool is in compression.

[0028] FIG. 4 illustrates flow channels machined into upper spring wear ring 322 and spring mandrel 321 to allow oil to flow freely within oil chamber 101 of shock tool 100, and thus prevent the undesirable formation of isolated oil pockets within oil chamber 101. If localized pockets of oil form within oil chamber 101, the static pressure of such oil pockets may increase or decrease significantly due to compression and expansion of disc spring stack 323, potentially leading to sealing failures.

[0029] Upper spring wear ring 322 has slots or channels 328 and radial holes 329 drilled through a shoulder thereof to allow oil to flow freely while the disc spring stack 323 compresses and expands. Additionally, spring mandrel 321 surface is etched with grooves or channels 330 to permit the flow of oil radially under disc spring stack 323 as shock tool 100 is subjected to extreme axial and lateral shock impulses, and as it compresses and expands longitudinally during shock absorption. The grooves 330 in spring mandrel 321 facilitate the flow of oil underneath lower spring wear ring 324 and through the drilled holes 331 in seal mandrel 325 to balancing piston 401. These linked internal fluid passageways 328, 329, 330, and 331 allow oil flow freely along the length of the tool 100.

[0030] During typical drilling operations, the downward axial force acting on the drill string is the load applied by the drilling machine and the upward force acting on the drill string is the resultant (i.e., reaction) force originating from the drill bit. The magnitudes of both forces are essentially constant throughout the drilling process. However, there are small but dynamic impulses that sharply accelerate the drill string, as a result of particular drilling practices (e.g., jarring tools, agitators, perforating tools, etc.) and/or variations in subsurface formation characteristics. Shock tool 100 is designed to minimize the effects of such loads and impulses on the drill string.

[0031] Disc spring stack 323 is pre-set, or pre-compressed, longitudinally between upper spring wear ring 322 and lower spring wear ring 324. Therefore, there is a minimum load that must be overcome before disc spring stack 323 will compress further. In most cases, the weight-on-bit (WOB) during normal drilling operations is more than the load threshold of the shock absorber, so that in the absence of shock impulse loads, disc spring stack 323 operates from a further- compressed, or neutral, equilibrium state. Therefore, any axial shock impulse transmitted to shock tool 100 will either compress or expand disc spring stack 323 (depending on the axial direction of the shock impulse).

[0032] FIG. 5 illustrates the compression of shock tool 100 in response to shock loading. When a shock impulse occurs, the dynamic load must pass through disc spring stack 323 before continuing through shock tool 100 toward the other end. As this happens, some energy from the impulse compresses disc spring stack 323 and shock tool 100 accordingly. As a result, the dynamic load transferred from shock tool 100 to the drill string is significantly less than the dynamic load applied to shock tool 100.

[0033] More specifically, a dynamic load originating from below shock tool 100 and travelling upward through the tool, is applied to shock tool 100 via threaded connection (not shown) to bottom sub 102, and is transferred through the outer tubular componentsin the uphole direction into lower spring housing 312 and, therefore, into lower spring wear ring 324, which compresses disc spring stack 323 upward and into upper spring wear ring 322 that shoulders spline mandrel 211. Since spline mandrel 211 (and therefore all inner tubular components) is threadingly fixed to the lower end of the drill string, the outer tubular assembly slides telescopically upward and downward alongside disc spring stack 323 as it compresses and expands. For this reason, shock tool 100 is preferably installed between the source of dynamic loads and the at-risk components (such as data-collecting devices).

[0034] For example, to protect surface equipment from persistent oscillating loads produced from an agitator, a shock tool 100 could be installed above the agitator in the drill string so that dynamic loads traveling upward, towards the surface, are reduced as they pass through shock tool 100, due to compression of disc spring stack 323.

[0035] FIG. 5A illustrates disc spring stack 323 when subjected to normal drilling forces only. In this state, there is no large impulse being absorbed by shock tool 100, and shock tool 100 is oriented near its equilibrium (or “neutral”) position. FIG. 5A thus represents standard conditions of shock tool 100 in a state that has potential to absorb a sudden jarring acceleration at any instant. [0036] In FIG. 5B, shock tool 100 is shown absorbing a large dynamic load 326 created from an external process such as an agitator. Since the shock impulse force is much larger than the equilibrium load, disc spring stack 323 compresses, the outer tubular assembly translates upward relative to the inner tubular assembly, and the overall length of shock tool 100 is shortened to absorb the shock impulse force. This telescopic motion of the outer tubular assembly relative to the inner tubular assembly during the absorption of dynamic loads may be seen by comparing the end point 103 of the inner tubular assemblyin FIG. 5A with the end point 103 of the inner tubular assembly in FIG. 5B within bottom sub 102.

[0037] The stiffness of disc spring stack 323 can be modified at surface by altering the number of disc springs in the stack, by altering the orientation of the disc springs that make up disc spring stack 323, or by manufacturing the disc springs from a material with different physical properties to produce different shock load absorption rates.

[0038] FIG. 6 details the sealing mechanisms implemented on the upper and lower end ofoil chamber 101 of shock tool 100. The pressure seal housing 223 comprises a grease section bounded by a wiper seal 214; a grease plug 215; and a high-pressure multiple-lip seal 212 that completely fills the grease chamber 218 at the top of shock tool 100 with grease to form a grease seal. The axial length of the grease section is greater than the stroke length (which would typically be about 2 inches (5 cm)) of shock tool 100 so that the grease seal remains effective as shock tool 100 is subjected to high-frequency vibrations (such as, for example, 20Hz oscillations from typical drill string agitators) and axial shock impulse loads (such as 65,000-pound forces from a typical drilling jar), and as the outer assembly of shock tool 100 consequently translates axially. This arrangement results in along-lasting seal and reliable lubrication to the high-pressure multiple-lip seal 212.

[0039] Additionally, the high-pressure multiple-lip seal 212 provides internal sealing to prevent infiltration of oil from shock tool 100 into the grease seal during extreme shock impulses, and provides a lasting seal against persistent high-frequency wear during the occurrence of both intended and incidental vibrations and shock impulses. Althoughshock tool 100 could use a single-lip, high-pressure seal in alternative embodiments, a multiple-lip seal is preferable because it has a larger contact surface area than a single-lip high-pressure seal, resulting in comparatively less friction during sliding such that shock tool 100 will be more resistant to sliding-induced wear than if it used a single-lip high- pressure seal.

[0040] To balance the static pressure increase caused by thermal expansion of the oil in oil chamber 101 as the oil temperature increases from surface temperatures to downhole environment temperatures, a balance piston 401 is coaxially installed over seal mandrel 325, and inside of a seal housing 411, to isolate oil chamber 101 from the open chamber 406 drilling mud, shown in FIG. 6. Balance piston 401 slides longitudinally on seal mandrel 325 to equalize the pressure in oil chamber 101 as the volume of the spring oil fluctuates due to temperature change.

[0041] Balance piston 401 features scraper seals 404/405 to prevent drilling mud particles from interfering with the balance piston’s ability to slide longitudinally and from entering the annular groove carrying high-pressure seals 402/403 and impairing their sealing capabilities. A Teflon- seated, energized quad seal 402 is used on the outer surface of piston 401 so that during every stroke of shock tool 100, as the outer tubular assembly moves upward or downward over balance piston 401, a long-lasting, high-pressure and low-friction seal is maintained. Oil chamber 101 is filled via oil ports 217 and 315 and sealed with plugs 216 and 314.

[0042] It will be readily appreciated by those skilled in the art that various alternative embodiments may be devised without departing from the scope of the present teachings, including modifications that may use equivalent structures or materials subsequently conceived or developed. [0043] It is to be especially understood that it is not intended for apparatus in accordance with the present disclosure to be limited to any described or illustrated embodiment, and that the substitution of a variant of a claimed element or feature, without any substantial resultantchange in the working of the apparatus and methods, will not constitute a departure from thescope of the disclosure.

[0044] In this patent document, any form of the word “comprise” is to be understood inits non limiting sense to mean that any element or feature following such word is included, but elements or features not specifically mentioned are not excluded. A reference to an element or feature by the indefinite article "a" does not exclude the possibility that more than one of such element or feature is present, unless the context clearly requires that there be one and only one such element or feature.

[0045] Any use of any form of the terms "connect", "engage", "couple", “latch”, "attach", or any other term describing an interaction between elements is not meant to limit the interaction to direct interaction between the subject elements, and may also includeindirect interaction between the elements such as through secondary or intermediary structure.

[0046] Relational and conformational terms such as (but not limited to) “vertical”, “horizontal”, “coaxial”, and “cylindrical” are not intended to denote or require absolute mathematical or geometrical precision. Accordingly, such terms are to be understood as denoting or requiring substantial precision only (e.g., “substantially vertical” or “generally cylindrical”) unless the context clearly requires otherwise.

Claims

1. A shock tool for disposal in a wellbore on a drill string, comprising: an inner tubular assembly having a first end and a second end; the inner tubular assembly having a connector at the first end for coupling to the drill string; an outer tubular housing having a first end, a second end, and an internal bore; the outer tubular housing having a connector at the second end for coupling to the drill string; the second end of the inner tubular assembly telescopically received within the bore at the first end of the outer tubular housing; a spring assembly disposed between the first end of the inner tubular assembly and the second end of the outer tubular housing; a sealed internal fluid chamber to contain a lubricating fluid, wherein the fluid chamber is linked to internal fluid passageways to allow flow of the lubricating fluid internally along the length of the tool; and a piston to isolate the internal fluid chamber from drilling fluid.

2. The shock tool of claim 1 wherein the internal fluid passageways comprise channels formed on the inner tubular assembly to facilitate telescopic coaxial movement between the inner tubular assembly and the outer tubular housing.

3. The shock tool of claim 2 wherein the internal fluid passageways allow lubricating fluid flow to the spring assembly.

4. The shock tool of claim 1 wherein the inner tubular assembly comprises: a housing having longitudinal spline ridge cuts on an interior surface thereof; a mandrel having spline ridge protrusions on an exterior surface thereof; the mandrel disposed within the housing with the spline ridge protrusions matingly engaged with the housing spline ridge cuts to permit torque transfer between the mandrel and the housing.

5. The shock tool of claim 4 wherein at least one of the spline ridge protrusions on the mandrel has an angled surface to provide a flow channel for the lubricating fluid when the spline ridge protrusion is matingly engaged with a housing spline ridge cut.

6. The shock tool of claim 1 further comprising a seal arrangement to prevent drilling fluid from contaminating an annulus between the inner tubular assembly and an inner surface of the outer tubular housing.

7. The shock tool of claim 6 wherein the seal arrangement comprises a first annular seal disposed proximate the first end of the outer tubular housing and a second annular seal spaced apart from the first seal.

8. The shock tool of claim 7 further comprising an internal chamber to contain a grease compound, wherein the chamber resides between the first annular seal and the second annular seal.

9. The shock tool of claim 8 wherein the internal chamber provides a grease seal when a grease compound is disposed in the chamber.

10. The shock tool of claim 8 wherein the axial length of the internal grease chamber is at least equal to a stroke length of the outer tubular housing when the outer tubular housing translates axially in relation to the inner tubular assembly.

11. A method of absorbing axial loads on a drill sting positioned in a wellbore, comprising: disposing a shock tool in a drill string, the shock tool including: an inner tubular assembly having a first end and a second end; the inner tubular assembly having a connector at the first end for coupling to the drill string; an outer tubular housing having a first end, a second end, and an internal bore; the outer tubular housing having a connector at the second end for coupling to the drill string; the second end of the inner tubular assembly telescopically received within the bore at the first end of the outer tubular housing; a spring assembly disposed between the first end of the inner tubular assembly and the second end of the outer tubular housing; a sealed internal fluid chamber to contain a lubricating fluid, wherein the fluid chamber is linked to internal fluid passageways to allow flow of the lubricating fluid internally along the length of the tool; and a piston to isolate the internal fluid chamber from drilling fluid.

12. The method of claim 11 wherein the internal fluid passageways comprise channels formed on the inner tubular assembly to facilitate telescopic coaxial movement between the inner tubular assembly and the outer tubular housing.

13. The method of claim 12 wherein the internal fluid passageways allow lubricating fluid flow to the spring assembly.

14. The method of claim 11 wherein the inner tubular assembly comprises: a housing having longitudinal spline ridge cuts on an interior surface thereof; a mandrel having spline ridge protrusions on an exterior surface thereof; the mandrel disposed within the housing with the spline ridge protrusions matingly engaged with the housing spline ridge cuts to permit torque transfer between the mandrel and the housing.

15. The method of claim 14 wherein at least one of the spline ridge protrusions on the mandrel has an angled surface to provide a flow channel for the lubricating fluid when the spline ridge protrusion is matingly engaged with a housing spline ridge cut.

16. The method of claim 11 further comprising preventing drilling fluid from contaminating an annulus between the inner tubular assembly and an inner surface of the outer tubular housing via a seal arrangement.

17. The method of claim 16 wherein the seal arrangement comprises a first annular seal disposed proximate the first end of the outer tubular housing and a second annular seal spaced apart from the first seal.

18. The method of claim 17 further comprising disposing a grease compound in an internal chamber residing between the first annular seal and the second annular seal.

19. The method of claim 18 wherein the internal chamber provides a grease seal when a grease compound is disposed in the chamber.

20. The method of claim 18 wherein the axial length of the internal grease chamber is at least equal to a stroke length of the outer tubular housing when the outer tubular housing translates axially in relation to the inner tubular assembly.