Collet-type mechanism for gripping workpieces of different sizes

Abstract

A collet mechanism includes a collet receiver and a segmented collet assembly incorporating multiple collet segments. The collet receiver defines a conical receiver contact surface, and each collet segment defines multiple radially-stepped collet segment contact surfaces, each slidingly engageable with the receiver contact surface, such that the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the collet segment contact surface engaging the receiver contact surface. In a variant embodiment, the collet receiver defines multiple radially- stepped conical receiver contact surfaces, and each collet segment defines a collet segment contact surface slidingly engageable with each receiver contact surface, such that the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the receiver contact surface engaged by the collet segment contact surfaces.

Description

[0001] COLLET-TYPE MECHANISM FOR GRIPPING WORKPIECES OF DIFFERENT SIZES

[0002] FIELD

[0003] The present disclosure relates in general to collet-type and slips-type mechanisms for releasably gripping an object or workpiece. Such a mechanism comprises a collet receiver and a segmented collet assembly, and has a longitudinal collet receiver axis (alternatively referred to herein as a “receiver axis”). Axial displacement of the workpiece relative to the mechanism is resisted when axial force is transferred in one direction between the collet receiver and the segmented collet assembly, with correlative axial movement between the collet receiver and the segmented collet assembly. The mechanism releases the workpiece when the direction of axial movement is sufficiently reversed. More specifically, the present disclosure relates to collet-type mechanisms adaptable for gripping workpieces of different nominal sizes.

[0004] BACKGROUND

[0005] Collet-type mechanisms have been used in a wide variety of devices for well over one hundred years. Examples of collet-type mechanisms can be found in many devices, including but not limited to:

[0006] • Chucks on milling machines used to hold tooling;

[0007] • Chucks on multi-bit screwdrivers used to hold bits;

[0008] • Chucks on telescoping leg assemblies used to lock the positions of concentric leg segments relative to each other;

[0009] • Slips on drilling rigs used to hold pipe strings; and

[0010] • Tubular running tools, such as tools described in U.S. Patent No. 7,909,120 (Slack), U.S. Patent No. 11,167,358 (Slack and Yung), U.S. Patent No. 11,560,761 (Slack) and U.S. Patent No. 12,168,907 (Slack).

[0011] A collet-type mechanism (alternatively referred to herein as simply a “collet mechanism”) offers numerous advantages including the following: • Self-centering of the workpiece relative to the collet mechanism;

[0012] • Precise centering of the workpiece relative to the collet mechanism;

[0013] • Strong gripping of the workpiece;

[0014] • Resistance to the workpiece being jarred loose (i.e., untightened); and

[0015] • Ability to quickly release and change the workpiece being gripped.

[0016] Collet mechanisms that grip an external surface of a workpiece are generally known as external collet mechanisms. Collet mechanisms that grip an internal surface of a workpiece are generally known as internal collet mechanisms. Typically, the workpiece gripped by a collet mechanism is elongate and has a longitudinal workpiece axis that is coincident with the collet receiver axis. The surface of the workpiece that is gripped (alternatively referred to herein as the gripped workpiece surface) may be a cylindrical surface, but alternatively may be a non-cylindrical surface (for example, bits for multi-bit screwdrivers commonly have gripped workpiece surfaces configured as the six planar lateral surfaces of a hexagonal prism).

[0017] Typically, a collet mechanism incorporates two primary components:

[0018] • a collet receiver (or simply “receiver”), and

[0019] • a segmented collet assembly (alternatively referred to herein as a “segmented collet” or, more simply, a “collet”) comprising a plurality of collet segments.

[0020] The collet receiver has a receiver contact surface configured as a curved lateral surface of a truncated right circular cone. Each collet segment has a collet segment contact surface configured for sliding contact with the receiver contact surface. Each collet segment contact surface also may be configured as a curved lateral surface of a truncated right circular cone, but alternatively may be configured at least partly as a curved lateral surface of a right or oblique circular cylinder to improve the contact conditions between the collet segment contact surfaces and the receiver contact surface, as described in US 11,167,358.

[0021] Each collet segment also defines a workpiece engagement surface oriented in a radial direction opposite to that of the collet segment contact surface. In the assembled collet mechanism, the workpiece engagement surfaces of the plurality of collet segments collectively define a discontinuous surface (referred to herein as a “grip surface”) that is symmetric about the receiver axis but will change in size in response to relative axial movement between the segmented collet and the receiver. The workpiece engagement surfaces are configured to grippingly engage a workpiece.

[0022] The collet segments function as wedges between the receiver and the workpiece to transform axial movement of the collet relative to the receiver in one direction into radial movement of the grip surface causing engagement with the workpiece. When the grip surface is in gripping engagement with the workpiece, axial force acting on the collet assembly in the one direction and reacted by the receiver will induce radial force between the grip surface and the gripped workpiece surface. Gripping engagement between the grip surface and the gripped workpiece surface restrains movement of the workpiece relative to the collet assembly and thus also relative to the receiver. The collet mechanism releases the workpiece when the direction of axial movement is sufficiently reversed. Therefore, a releasable rigid connection is formed between the workpiece and the collet mechanism, enabling the transfer of axial, torsional, bending, and shear loads between the workpiece and the receiver. Axial force may be applied directly to the collet, and / or from the workpiece across the grip surface to the collet.

[0023] In a typical collet mechanism, the axial force applied to the collet assembly must induce a radial force significantly greater than the shear load carried across the grip surface interface. The taper angle (or slope) of the receiver contact surface, relative to the receiver axis, controls the magnitude of the axial-to-radial force amplification (alternatively referred to herein as the mechanical advantage). A decreased slope or taper angle relative to the receiver axis results in a system with a greater mechanical advantage, and vice versa.

[0024] As used in the present disclosure, the term “collet segment” is to be understood as meaning a segment of a segmented collet. The collet segments of a segmented collet may be physically separate from each other, or may be coupled by suitable means permitting a selected degree of relative movement of the collet segments in the tangential and radial directions (when not constrained by a collet receiver) but constrained to be aligned in the axial direction. Non-limiting examples of means for permitting relative movement between coupled collet segments include the provision of integral attachment of the collet segments through flexural spring arms to a common ring, or having the collet segments axially retained within windows of a cage.

[0025] The range of workpiece sizes that can be gripped by prior art collet mechanisms is a function of:

[0026] • the taper angle of the contacting surfaces of the collet segments and the collet receiver relative to the receiver axis; and

[0027] • the maximum axial distance that the segmented collet can move relative to the collet receiver (alternatively referred to herein as the “axial collet stroke length”), as limited by the requirement for sufficient contact length (or overlap) of the receiver contact surface with the collet segment contact surface to carry the radial force induced when gripping a workpiece.

[0028] For an internal collet, the collet segments move radially outward with increasing axial collet stroke. For an external collet, the collet segments move radially inward with increasing axial collet stroke.

[0029] The collet grip range R may be defined as the available radial stroke of a segmented collet, and can be increased by increasing one or both of the receiver contact surface taper angle 0 and the axial collet stroke length L:

[0030] Equation 1 : R oc L x tan 0

[0031] Increasing the taper angle 0 will decrease the mechanical advantage and, correspondingly, the gripping force of the collet mechanism, which is usually undesirable. As a result, increasing the axial collet stroke length (and thus the length of the collet mechanism) has been the primary method for increasing the collet grip range. Accordingly, prior art collet mechanisms can be designed to grip workpieces of different sizes by increasing the axial collet stroke length until the desired radial stroke is achieved, or (as commonly done with milling machines) by using a different segmented collet for a workpiece of a different size.

[0032] Certain categories of workpieces may not require a collet mechanism with a continuous grip range because the workpieces are provided in multiple nominal sizes with non-overlapping dimensional tolerance ranges. The gripping range of some prior art collet mechanisms may be changed by removing the segmented collet assembly that is configured for a first gripping range and installing a different segmented collet assembly that is configured for a second gripping range.

[0033] For example, the cross-sectional dimensions of tubular components used in casing strings for petroleum wells is defined by the American Petroleum Institute (API) Specification 5CT. The nominal outside diameter of an API casing size differs from the next smaller or larger casing size by roughly 10%, and the permitted tolerance range of outside diameter is from -0.5% to +1% of the nominal outside diameter. It is common for the nominal diameter of a casing string to be incrementally changed at selected intervals along its length; typically, the difference between axially-adjacent sections of the casing string is only one standard API casing size. It would be beneficial in casing running operations of such strings to have a collet mechanism capable of gripping workpieces of two or more discrete sizes while having a shorter axial length than prior art mechanisms providing a comparable grip range, and without needing to change the segmented collet to grip workpieces of multiple sizes.

[0034] BRIEF SUMMARY OF THE DISCLOSURE

[0035] In general terms, the present disclosure teaches embodiments of a collet mechanism that can selectively grip workpieces within a range of different nominal workpiece sizes, while having an axial length less than that of conventional collet mechanisms capable of gripping workpieces within the same range of nominal workpiece sizes. Collet mechanisms in accordance with the present disclosure achieve this either by configuring each collet segment contact surface as a radially- stepped contact surface or by configuring the receiver contact surface as a radially- stepped contact surface, and thus providing the collet mechanism with a radially- stepped (i.e., non-continuous) grip range that is greater than the grip range possible with a conventional collet mechanism having the same axial length and receiver contact surface taper angle.

[0036] In preferred embodiments, each collet segment defines two or more separate and longitudinally-aligned collet segment contact surfaces that can be selected from, by the user, to contact the receiver contact surface, according to the nominal workpiece size intended to be gripped by the collet mechanism. A collet segment adjustment surface is provided between each two adjacent collet segment contact surfaces to facilitate transitioning of the mechanism between different nominal- workpiece- size configurations (with the axial position of the collet assembly relative to the collet receiver changing accordingly).

[0037] In one non-limiting embodiment, an external collet mechanism in accordance with the present disclosure is configured with two discrete grip ranges. The mechanism has a collet receiver having a receiver axis and an axisymmetric inner profile (i.e., receiver bore) defining a receiver contact surface configured as a curved lateral surface of a first truncated right circular cone and an axially-contiguous receiver adjustment surface configured as a curved lateral surface of a second truncated right circular cone, with the receiver adjustment surface being provided at the axial end of the receiver contact surface having the largest diameter. The taper angle of the receiver adjustment surface (relative to the receiver axis) is greater than the taper angle of the receiver contact surface.

[0038] The segmented collet comprises a plurality of collet segments, with the segmented collet having a radially- outer profile defining three axially-contiguous surfaces, in sequence:

[0039] 1. a first collet segment contact surface associated with a first nominal workpiece size;

[0040] 2. a collet segment adjustment surface; and

[0041] 3. a second collet segment contact surface associated with a second nominal workpiece size.

[0042] Each of the first and second collet segment contact surfaces may be configured:

[0043] • as a curved lateral surface of a truncated right circular cone;

[0044] • at least partially as a curved lateral surface of a right circular cylinder according to US 11,167,358; or

[0045] • at least partially as a curved lateral surface of an oblique circular cylinder according to US 11,167,358. Although it might commonly be desirable for the first and second collet segment contact surfaces to have the same configurations, the present disclosure also contemplates variant embodiments in which the first and second collet segment contact surfaces have different configurations (such as, by way of non-limiting example, embodiments in which the first collet segment contact surfaces are configured as curved lateral surfaces of a truncated right circular cone, and the second collet segment contact surfaces are configured at least partially as curved lateral surfaces of an oblique circular cylinder.

[0046] The first and second collet segment contact surfaces are configured to match the taper of the receiver contact surface, and are alternatively engageable with the collet receiver depending on the nominal size of the workpiece to be gripped by the collet mechanism. The collet segment adjustment surface is configured for sliding engagement with the receiver adjustment surface facilitating radial movement of the collet segments when transitioning between contact of the first collet segment contact surfaces with the receiver contact surface and contact of the second collet segment contact surfaces with the receiver contact surface (and vice versa). The collet segments have inner profiles collectively defining a radially-internal grip surface.

[0047] In another non-limiting embodiment, an internal collet mechanism in accordance with the present disclosure is configured with two discrete grip ranges. The mechanism has a collet receiver having a receiver axis and an axisymmetric outer profile defining a receiver contact surface configured as a curved lateral surface of a first truncated right circular cone and an axially-contiguous receiver adjustment surface configured as a curved lateral surface of a second truncated right circular cone, with the receiver adjustment surface being provided at the axial end of the receiver contact surface having the smallest diameter. The taper angle of the receiver adjustment surface (relative to the receiver axis) is greater than the taper angle of the receiver contact surface.

[0048] The segmented collet comprises a plurality of collet segments, with the segmented collet having a radially-inner profile forming three axially-contiguous surfaces, in sequence:

[0049] 1. a first collet segment contact surface associated with a first nominal workpiece size; 2. a collet segment adjustment surface; and

[0050] 3. a second collet segment contact surface associated with a second nominal workpiece size.

[0051] Each of the first and second collet segment contact surfaces may be configured:

[0052] • as a curved lateral surface of a truncated right circular cone;

[0053] • at least partially as a curved lateral surface of a right circular cylinder; or

[0054] • at least partially as a curved lateral surface of an oblique circular cylinder.

[0055] The first and second collet segment contact surfaces are configured to match the taper of the receiver contact surface, and are alternatively engageable with the collet receiver depending on the nominal size of the workpiece to be gripped by the collet mechanism. The collet segment adjustment surface is configured for sliding engagement with the receiver adjustment surface facilitating radial movement of the collet segments when transitioning between contact of the first collet segment contact surfaces with the receiver contact surface and contact of the second collet segment contact surfaces with the receiver contact surface (and vice versa). The collet segments have outer profiles collectively defining a radially-external grip surface.

[0056] Alternative embodiments of either externally- gripping or internally- gripping collets in accordance with the present disclosure provide a “radially-stepped” (i.e., non- continuous) grip range by forming the collet receiver with two or more separate and longitudinally- aligned receiver contact surfaces either of which can be selected to contact a collet segment contact surface. Adjacent receiver contact surfaces are axially contiguous with a receiver adjustment surface. Otherwise stated, instead of providing one or more stepped contact surfaces on the collet segments, the stepped contact surfaces may alternatively be provided on the collet receiver as curved lateral surfaces of two or more truncated right circular cones.

[0057] In summary, the present disclosure teaches two primary variants of a collet mechanism that is configurable to grip workpieces of two or more different sizes, and which comprises a collet receiver having a longitudinal receiver axis and a segmented collet assembly comprising a plurality of collet segments. In the first primary variant of this collet mechanism, the collet receiver defines:

[0058] • an axisymmetric receiver contact surface configured as a curved lateral surface of a first truncated right circular cone having a first taper angle relative to the receiver axis; and

[0059] • an axisymmetric receiver adjustment surface contiguous with the receiver contact surface, and configured as a curved lateral surface of a second truncated right circular cone having a second taper angle relative to the receiver axis, with the second taper angle being greater than the first taper angle.

[0060] Each collet segment defines:

[0061] • a workpiece engagement surface configured for gripping an elongate workpiece;

[0062] • two or more separate and longitudinally-aligned collet segment contact surfaces, each configured for longitudinally-sliding engagement with the receiver contact surface; and

[0063] • one or more collet segment adjustment surfaces, each disposed between and longitudinally contiguous with two of the two or more collet segment contact surfaces, and each configured for longitudinally-sliding engagement with the receiver adjustment surface.

[0064] Accordingly, this first primary variant of the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the collet segment contact surfaces engaging the receiver contact surface. The collet mechanism may be configured for gripping either an external surface or an internal surface of a workpiece. Optionally, at least one of the two or more collet segment contact surfaces of each collet segment may be configured at least partly as a curved lateral surface of either an oblique circular cylinder or a right circular cylinder.

[0065] In the second primary variant of this collet mechanism, the collet receiver defines, in longitudinal sequence: • a first axisymmetric receiver contact surface configured as a curved lateral surface of a first truncated right circular cone having a first taper angle relative to the receiver axis;

[0066] • an axisymmetric receiver adjustment surface configured as a curved lateral surface of a second truncated right circular cone having a second taper angle relative to the receiver axis, with the second taper angle being greater than the first taper angle, and with the receiver adjustment surface being longitudinally contiguous with the first receiver contact surface; and

[0067] • a second axisymmetric receiver contact surface configured as a curved lateral surface of a third truncated right circular cone having the first taper angle, with the second receiver contact surface being longitudinally contiguous with the receiver adjustment surface.

[0068] Each collet segment defines:

[0069] • a workpiece engagement surface configured for gripping an elongate workpiece;

[0070] • a collet segment contact surface configured for longitudinally- sliding engagement with a user-selected one of the first and second receiver contact surfaces; and

[0071] • a collet segment adjustment surface longitudinally-contiguous with the collet segment contact surface, and configured for longitudinally- sliding engagement with the receiver adjustment surface.

[0072] Accordingly, this second primary variant of the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the receiver contact surface engaged by the collet segment contact surface. As with the first primary variant, this second primary variant of the collet mechanism may be configured for gripping either an external surface or an internal surface of a workpiece, and at least one of the two or more collet segment contact surfaces of each collet segment optionally may be configured at least partly as a curved lateral surface of either an oblique circular cylinder or a right circular cylinder.

[0073] The present disclosure also teaches variants of a tubular running tool incorporating a collet mechanism generally in accordance with a selected one of the two primary collet mechanism variants described above. The tubular running tool may be either an externally- gripping tubular running tool or an internally-gripping tubular running tool.

[0074] BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Embodiments in accordance with the present disclosure will now be described with reference to the accompanying Figures, in which numerical references denote like parts, and in which:

[0076] FIGURE 1A and IB are longitudinal section and isometric views of a first prior art external collet mechanism, shown configured with a first segmented collet and engaging a first- size workpiece.

[0077] FIGURE 2A and 2B are longitudinal section and isometric views of the collet mechanism in FIGS. 1A and IB, shown reconfigured with a second segmented collet and engaging a second- size workpiece.

[0078] FIGURE 3A is a longitudinal section of a second prior art external collet mechanism engaging a first- size workpiece.

[0079] FIGURE 3B is a longitudinal section of the collet mechanism shown in FIG. 3A engaging a second- size workpiece.

[0080] FIGURE 4A and 4B are longitudinal section and isometric views of an embodiment of an external collet mechanism having two grip ranges in accordance with the present disclosure, and shown engaging a first-size workpiece in the larger of the two grip ranges.

[0081] FIGURE 5A and 5B are isometric and longitudinal section views of the collet receiver of the collet mechanism shown in FIGS. 4A and 4B.

[0082] FIGURE 6A and 6B are isometric and longitudinal section views of a collet segment of the collet mechanism shown in FIGS. 4A and 4B. FIGURE 7A and 7B are longitudinal section and isometric views of the collet mechanism in FIGS. 4A and 4B, shown engaging a second-size workpiece in the smaller of the two grip ranges.

[0083] FIGURE 8 is a longitudinal section through the collet mechanism in FIGS. 4A and 4B, shown with the segmented collet assembly at an intermediate axial position in which the segmented collet assembly is being adjusted to change the grip range.

[0084] FIGURE 9A is a longitudinal section through an embodiment of an internal collet mechanism having two grip ranges in accordance with the present disclosure, and shown engaging a first-size workpiece in the smaller of the collet mechanism’s two grip ranges.

[0085] FIGURE 9B is a longitudinal section through the collet mechanism in FIG. 6A, shown engaging a workpiece in the larger of the two grip ranges.

[0086] FIGURE 10A is a longitudinal section through an embodiment of an external collet mechanism having three grip ranges in accordance with the present disclosure, and shown engaging a workpiece in a first one of the three grip ranges.

[0087] FIGURE 10B is a longitudinal section through the collet mechanism in FIG. 10A, shown engaging a workpiece in a second one of the three grip ranges.

[0088] FIGURE IOC is a longitudinal section through the collet mechanism in FIG. 10A, shown engaging a workpiece in a third one of the three grip ranges.

[0089] FIGURE 11A is a longitudinal section through another embodiment of an external collet mechanism having two grip ranges in accordance with the present disclosure, and shown engaging a workpiece in the larger of the two grip ranges.

[0090] FIGURE 11B is a longitudinal section through the collet mechanism in FIG. 11A, shown engaging a workpiece in the smaller of the two grip ranges. FIGURE 12 is an isometric view of the collet receiver of the collet mechanism shown in FIGS. 11A and 11B.

[0091] FIGURE 13 is an isometric view of a collet segment of the collet mechanism shown in FIGS. 11A and 11B.

[0092] FIGURE 14A and 14B are front elevation and longitudinal section views of an externally- gripping casing running tool (CRT) incorporating an embodiment of a collet mechanism in accordance with the present disclosure.

[0093] FIGURE 15 is a longitudinal section through the lower mandrel of the CRT in FIGS. 14A and 14B.

[0094] FIGURE 16A and 16B are side and front elevation views of a gripping element of the CRT in FIGS. 14A and 14B.

[0095] FIGURE 17 is a longitudinal section through the CRT in FIGS. 14A and 14B, shown with the CRT gripping a casing joint of a first nominal size.

[0096] FIGURE 18 is a longitudinal section through the CRT in FIGS. 14A and 14B, shown with the CRT gripping a casing joint of a second nominal size.

[0097] DETAIEED DESCRIPTION

[0098] FIGS. 1A and IB are longitudinal section and isometric views of an embodiment 100 of a first prior art external collet mechanism. Collet mechanism 100 comprises a collet receiver 190 having a longitudinal axis 199, and a first segmented collet assembly 110. Collet receiver 190 has an axisymmetric bore defining a receiver contact surface 191 configured as a curved lateral surface of a first truncated right circular cone. First segmented collet assembly 110 comprises a plurality of collet segments 111 configured to engage a first- size workpiece 901. Each collet segment 111 has a radially-intemal workpiece engagement surface 113 and a radially-extemal profile defining a collet segment contact surface 112 configured as a curved lateral surface of a first truncated right circular cone with a taper angle matching the taper angle of receiver contact surface 191.

[0099] Collet mechanism 100 has a limited axial (and thus radial) stroking range. FIGS. 2A and 2B are longitudinal section and isometric views of collet mechanism 100 reconfigured with a second segmented collet assembly 120 replacing first segmented collet assembly 110. Second segmented collet assembly 120 comprises a plurality of collet segments 121 configured to engage a second-size workpiece 902. Each collet segment 121 has a radially - intemal workpiece engagement surface 123 and a radially-external profile defining a collet segment contact surface 122 configured as a curved lateral surface of a first truncated right circular cone with a taper angle matching the taper angle of receiver contact surface 191.

[0100] FIG. 3A is a longitudinal section of an embodiment 200 of a second prior art external collet mechanism shown engaging first- size workpiece 901. Collet mechanism 200 comprises a collet receiver 290 having a longitudinal axis 299, and a segmented collet assembly 210. Collet receiver 290 has an axisymmetric bore defining a receiver contact surface 291 configured as a curved lateral surface of a first truncated right circular cone. Segmented collet assembly 210 comprises a plurality of collet segments 211. Each collet segment 211 has a radially-intemal workpiece engagement surface 213 and a radially- external profile defining a collet segment contact surface 212 configured as a curved lateral surface of an oblique circular cylinder with the axis of the oblique circular cylinder oriented to match the taper angle of receiver contact surface 291 according to US 11,167,358. To grip first-size workpiece 910, segmented collet assembly 201 is positioned near the axial end of receiver contact surface 291 having the largest diameter.

[0101] Prior art collet mechanism 200 has a longer axial stroking range and, therefore, a longer radial stroking range, than prior art collet mechanism 100. FIG. 3B is a longitudinal section of collet mechanism 200 shown engaging second-size workpiece 902. Second-size workpiece 902 is smaller than first-size workpiece 901. To grip second-size workpiece 902, segmented collet assembly 201 is positioned near the axial end of receiver contact surface 291 having the smallest diameter. Embodiment 1 - External collet mechanism for 2 sizes of workpiece

[0102] FIGS. 4A and 4B are longitudinal section and isometric views, respectively, of a non-limiting embodiment 1000 of an external collet mechanism in accordance with the present disclosure, shown gripping a first-size workpiece 1301. Collet mechanism 1000 comprises a collet receiver 1100 having a longitudinal receiver axis 1109, and a segmented collet assembly 1200.

[0103] FIGS. 5 A and 5B, respectively, are an isometric view and a longitudinal section of collet receiver 1100. Collet receiver 1100 has an axisymmetric bore defining:

[0104] • a receiver contact surface 1101 configured as a curved lateral surface of a first truncated right circular cone; and

[0105] • a receiver adjustment surface 1102 configured as a curved lateral surface of a second truncated right circular cone.

[0106] Receiver adjustment surface 1102 is provided at the axial end of receiver contact surface 1101 having the largest diameter. The taper angle a of receiver adjustment surface 1102, relative to receiver axis 1109, is greater than the taper angle 6 of receiver contact surface 1101.

[0107] Segmented collet assembly 1200 comprises a plurality of collet segments 1210. FIGS. 6A and 6B, respectively, are an isometric view and a longitudinal section of a collet segment 1210. Each collet segment 1210 has a radially-intemal workpiece engagement surface 1214 and a radially-extemal profile defining:

[0108] • a first collet segment contact surface 1211;

[0109] • a collet segment adjustment surface 1212 axially contiguous with first collet segment contact surface 1211 and configured for axial sliding engagement with receiver adjustment surface 1102; and

[0110] • a second collet segment contact surface 1213 axially contiguous with collet segment adjustment surface 1212.

[0111] In this embodiment, each of first collet segment contact surface 1211 and second collet segment contact surface 1213 configured is as a curved lateral surface of a right circular cylinder with the axis of the oblique circular cylinder oriented to match the taper angle of receiver contact surface 1101 according to US 11,167,358. Collet segment adjustment surface 1212 is configured as a curved lateral surface of a truncated right circular cone with a taper angle a equal to the taper angle a of receiver adjustment surface 1102.

[0112] Collet segment contact surface 1211 defines a first grip range of collet mechanism 1000, and collet segment contact surface 1213 defines a second grip range of collet mechanism 1000. FIGS. 4A and 4B show collet mechanism 1000 gripping a first-size workpiece 1301 within the first grip range of collet mechanism 1000. In the first grip range, first collet segment contact surface 1211 of each collet segment 1210 is in sliding engagement with receiver contact surface 1101. FIGS. 7 A and 7B show collet mechanism 1000 gripping a second-size workpiece 1302 within the second grip range of collet mechanism 1000. In the second grip range, second collet segment contact surface 1213 of each collet segment 1210 is in sliding engagement with receiver contact surface 1101.

[0113] The grip range of collet mechanism 1000 is changeable by moving segmented collet assembly 1200 axially relative to collet receiver 1100, with a corresponding change in the radial position of collet segments 1210. Having reference to FIG. 8, and considering collet receiver 1100 as a stationary reference, movement of segmented collet assembly 1200 axially to the right will transition collet mechanism 1000 from the first grip range to the second grip range. Collet segment adjustment surfaces 1212 are slidingly engageable with receiver adjustment surface 1102 as shown in FIG. 5 to urge radially-inward movement of collet segments 1210 toward receiver axis 1109. Collet mechanism 1000 can be transitioned from the second grip range to the first grip range by moving segmented collet assembly 1200 axially to the left relative to collet receiver 1100. Collet segments 1210 may be urged radially outward relative to receiver axis 1109 by any suitable means known to persons of ordinary skill in the art such as but not limited to one or more mechanical springs (not shown).

[0114] Embodiment 2 - Internal collet mechanism for 2 sizes of workpiece

[0115] FIG. 9A is a longitudinal section through a non-limiting embodiment 2000 of an internal collet mechanism in accordance with the present disclosure, shown gripping a first- size workpiece 2301. Collet mechanism 2000 comprises a collet receiver 2100 having a longitudinal receiver axis 2109, and a segmented collet assembly 2200.

[0116] Collet receiver 2100 has an axisymmetric radially-external profile defining:

[0117] • a receiver contact surface 2101 configured as a curved lateral surface of a first truncated right circular cone; and

[0118] • a receiver adjustment surface 2102 configured as a curved lateral surface of a second truncated right circular cone.

[0119] Receiver adjustment surface 2102 is provided at the axial end of receiver contact surface 2101 having the smallest diameter. The taper angle of receiver adjustment surface 2102, relative to receiver axis 2109, is greater than the taper angle of receiver contact surface 2101.

[0120] Segmented collet assembly 2200 comprises a plurality of collet segments 2210. Each collet segment 2210 has a radially-external workpiece engagement surface 2214 and a radially-internal profile defining:

[0121] • a first collet segment contact surface 2211;

[0122] • a collet segment adjustment surface 2212 axially contiguous with first collet segment contact surface 2211 and configured for axial sliding engagement with receiver adjustment surface 2102; and

[0123] • a second collet segment contact surface 2213 axially contiguous with collet segment adjustment surface 2212.

[0124] In this embodiment, each of first collet segment contact surface 2211 and second collet segment contact surface 2213 is configured as a curved lateral surface of a right circular cylinder with the axis of the oblique circular cylinder oriented to match the taper angle of receiver contact surface 2101 according to US 11,167,358. Collet segment adjustment surface 2212 is configured as a curved lateral surface of a truncated right circular cone with a taper angle equal to the taper angle of receiver adjustment surface 2102.

[0125] Collet segment contact surface 2211 defines a first grip range of collet mechanism 1000, and collet segment contact surface 2213 defines a second grip range of collet mechanism 1000. FIG. 9A shows collet mechanism 2000 gripping a first-size workpiece 2301 within the first grip range of collet mechanism 2000. In the first grip range, first collet segment contact surface 2211 of each collet segment 2210 is in sliding contact with receiver contact surface 2101. FIG. 9B shows collet mechanism 2000 gripping a second- size workpiece 2302 within the second grip range of collet mechanism 2000. In the second grip range, second collet segment contact surface 2213 of each collet segment 2210 is in sliding engagement with receiver contact surface 2101.

[0126] The grip range of collet mechanism 2000 is changeable by moving segmented collet assembly 2200 axially relative to collet receiver 2100, with a corresponding change in the radial position of collet segments 2210. Having reference to FIGS. 9A and 9B, and considering collet receiver 2100 as a stationary reference, movement of segmented collet assembly 2200 axially to the right will transition collet mechanism 2000 from the first grip range to the second grip range. Collet segment adjustment surfaces 2212 are slidingly engageable with receiver adjustment surface 2102 to urge radially-outward movement of collet segments 2210 away from receiver axis 2109. Collet mechanism 2000 can be transitioned from the second grip range to the first grip range by moving segmented collet assembly 2200 axially to the left relative to collet receiver 2100. Collet segments 2210 may be urged radially inward relative to receiver axis 2109 by any suitable means known to persons of ordinary skill in the art such as but not limited to one or more mechanical springs (not shown).

[0127] Embodiment 3 - External collet mechanism for 3 sizes of workpiece

[0128] FIGS. 10A-10C illustrate another non-limiting embodiment 3000 of an internal collet mechanism in accordance with the present disclosure, shown gripping a first-size workpiece 3301. Collet mechanism 3000 comprises a collet receiver 3100 having a longitudinal axis 3109, and a segmented collet assembly 3200.

[0129] Collet receiver 3100 has an axisymmetric radially internal profile defining:

[0130] • a receiver contact surface 3101 configured as a curved lateral surface of a first truncated right circular cone; and

[0131] • a receiver adjustment surface 3102 configured as a curved lateral surface of a second truncated right circular cone. Receiver adjustment surface 3102 is provided at the axial end of receiver contact surface 3101 having the largest diameter. The taper angle of receiver adjustment surface 3102, relative to receiver axis 3109, is greater than the taper angle of the receiver contact surface

[0132] 3101.

[0133] Segmented collet assembly 3200 comprises a plurality of collet segments 3210. Each collet segment 3210 has a radially-internal workpiece engagement surface 3216 and a radially-extemal profile defining:

[0134] • a first collet segment contact surface 3211;

[0135] • a first collet segment adjustment surface 3212 axially contiguous with first collet segment contact surface 3211 and configured for axial sliding engagement with receiver adjustment surface 3102;

[0136] • a second collet segment contact surface 3213 axially contiguous with first collet segment adjustment surface 3212;

[0137] • a second collet segment adjustment surface 3214 axially contiguous with second collet segment contact surface 3213 and configured for axial sliding engagement with receiver adjustment surface 3102;

[0138] • a third collet segment contact surface 3215 axially contiguous with second collet segment adjustment surface 3214;

[0139] In this embodiment, each of first collet segment contact surface 3211, second collet segment contact surface 3213, and third collet segment contact surface 3215 is configured as a curved lateral surface of a right circular cylinder with the axis of the oblique circular cylinder oriented to match the taper angle of receiver contact surface 3101 according to US 11,167,358. Each of first collet segment adjustment surface 3212 and second collet segment adjustment surface 3214 is configured as a curved lateral surface of a truncated right circular cone with a taper angle equal to the taper angle of receiver adjustment surface

[0140] 3102.

[0141] First, second, and third collet segment contact surfaces 3211, 3213, and 3215 respectively define a first grip range, a second grip range, and a third grip range of collet mechanism 3000: • FIG. 10A shows collet mechanism 3000 gripping a first-size workpiece 3301 within the first grip range of collet mechanism 3000. In the first grip range, first collet segment contact surface 3211 of each collet segment 3210 is in sliding engagement with receiver contact surface 3101.

[0142] • FIG. 10B shows collet mechanism 3000 gripping a second-size workpiece 3302 within the second grip range of collet mechanism 3000. In the second grip range, second collet segment contact surface 3213 of each collet segment 3210 is in sliding engagement with receiver contact surface 3101.

[0143] • FIG. 10C shows collet mechanism 3000 gripping a third-size workpiece 3302 within the third grip range of collet mechanism 3000. In the third grip range, third collet segment contact surface 3215 of each collet segment 3210 is in sliding engagement with receiver contact surface 3101.

[0144] The grip range of collet mechanism 3000 is changeable by moving segmented collet assembly 3200 axially relative to collet receiver 3100, with a corresponding change in the radial position of collet segments 3210. Having reference to FIGS. 10A, 10B, and 10C, and considering collet receiver 3100 as a stationary reference, movement of segmented collet assembly 3200 axially to the right will transition collet mechanism 3000 from the first grip range to the second grip range, and from the second grip range to the third grip range. First collet segment adjustment surface 3212 and second collet segment adjustment surface 3214 will slidingly engage receiver adjustment surface 3102, urging radially inward movement of collet segments 3210 towards receiver axis 3109. Segmented collet assembly 3200 can be moved axially to the left relative to collet receiver 3100 to transition collet mechanism 3000 from the third grip range to the second grip range and from the second grip range to the first grip range. Collet segments 3210 may be urged radially inward relative to receiver axis 3109 by any suitable means known to persons of ordinary skill in the art such as but not limited to one or more mechanical springs (not shown).

[0145] Although not specifically described or illustrated herein, variant embodiments of internal collet mechanisms in accordance with the present disclosure can be readily configured by persons of ordinary skill in the art for gripping workpieces of three different sizes, in light of the foregoing description of a non-limiting embodiment of an external collet mechanism capable of gripping workpieces of three different sizes, and without going beyond the scope of the present disclosure.

[0146] Embodiment 4 - External collet mechanism with stepped receiver

[0147] FIG. 11 A is a longitudinal section of another non-limiting embodiment 4000 of an external collet mechanism in accordance with the present disclosure, gripping a first-size workpiece 4301. Collet mechanism 4000 comprises a collet receiver 4100 having a longitudinal axis 4109, and a segmented collet assembly 4200.

[0148] FIG. 12 is an isometric view of collet receiver 4100. Collet receiver 4100 has an axisymmetric bore defining:

[0149] • a first receiver contact surface 4101 configured as a curved lateral surface of a first truncated right circular cone;

[0150] • a receiver adjustment surface 4102 configured as a curved lateral surface of a second truncated right circular cone; and

[0151] • a second receiver contact surface 4103 configured as a curved lateral surface of a third truncated right circular cone.

[0152] First receiver contact surface 4101 and second receiver contact surface 4103 are axially contiguous with receiver adjustment surface 4102. The taper angle of first receiver contact surface 4101 is equal to the taper angle of second receiver contact surface 4103. The taper angle of receiver adjustment surface 1102 is greater than the taper angle of first receiver contact surface 4101 and second receiver contact surface 4103.

[0153] Segmented collet assembly 4200 comprises a plurality of collet segments 4210. FIG. 13 is an isometric view of a collet segment 4210. Each collet segment 4210 has a radially-intemal workpiece engagement surface 4213 and a radially-extemal profile defining:

[0154] • a collet segment contact surface 4211;

[0155] • a collet segment adjustment surface 4212 axially contiguous with collet segment contact surface 4211 and configured for axial sliding engagement with receiver adjustment surface 4102. In this embodiment, collet segment contact surface 4211 is configured as a curved lateral surface of a third truncated right circular cone with a taper angle equal to the taper angle of first receiver contact surface 4101 and second receiver contact surface 4103. Collet segment adjustment surface 4212 is configured as a curved lateral surface of a fourth truncated right circular cone with a taper angle equal to the taper angle of receiver adjustment surface 4102.

[0156] First and second receiver contact surfaces 4101 and 4103 respectively define a first grip range and a second grip range of collet mechanism 4000:

[0157] • FIG. 11 A shows collet mechanism 4000 gripping a first-size workpiece 4301 within the first grip range of collet mechanism 4000. In the first grip range, collet segment contact surface 4211 of each collet segment 4210 is in sliding engagement with first receiver contact surface 4101.

[0158] • FIG. 11B shows collet mechanism 4000 gripping a second-size workpiece 4302 within the second grip range of collet mechanism 4000. In the second grip range, collet segment contact surface 4211 of each collet segment 4210 is in sliding engagement with second receiver contact surface 4103.

[0159] The grip range of collet mechanism 4000 is changeable by moving segmented collet assembly 4200 axially relative to collet receiver 4100, with a corresponding change in the radial position of collet segments 4210. Having reference to FIGS. 11A and 11B, and considering collet receiver 4100 as a stationary reference, movement of segmented collet assembly 4200 axially to the right will transition collet mechanism 4000 from the first grip range to the second grip range. Collet segment adjustment surfaces 4212 will slidingly engage receiver adjustment surface 4102, urging radially-inward movement of collet segments 4210 toward receiver axis 4109. Segmented collet assembly 4200 can be moved axially to the left relative to collet receiver 4100 to transition collet mechanism 4000 from the second grip range to the first grip range. Collet segments 4210 may be urged radially outward relative to receiver axis 4109 by any suitable means known to persons of ordinary skill in the art such as but not limited to one or more mechanical springs (not shown). Embodiment 5 - Externally gripping casing running tool for 2 sizes of casing

[0160] FIG. 14A is a front elevation view of an externally-gripping casing running tool (CRT) 5000 (a type of tubular running tool) incorporating a non-limiting embodiment of a collet mechanism in accordance with the present disclosure. FIG. 14B is a longitudinal section through CRT 5000, which has a longitudinal axis 5001 and comprises:

[0161] • an axial extension linkage 5100 similar to axial extension linkages disclosed in U.S. 11,560,761;

[0162] • a latch release mechanism 5200 similar to latch release mechanisms disclosed in U.S. 12,168,907;

[0163] • a mandrel assembly 5300; and

[0164] • a gripping assembly 5400.

[0165] Mandrel assembly 5300 comprises a lower mandrel 5310 threadingly connected to an upper mandrel 5320. A mandrel lock ring 5330 prevents unintended loosening of a threaded connection between lower mandrel 5310 and upper mandrel 5320.

[0166] FIG. 15 is a longitudinal section through lower mandrel 5310. Lower mandrel 5310 has a longitudinal axis 5319 colinear with axis 5001, and acts as a collet receiver defining:

[0167] • mandrel contact surfaces 5311A, 5311B, 5311C, and 5311D; and

[0168] • mandrel adjustment surfaces 5312A, 5312B, 5312C, and 5312D.

[0169] Mandrel contact surfaces 5311A, 5311B, 5311C, and 5311D are configured as curved lateral surfaces of truncated right circular cones, all having the same taper angle. Mandrel adjustment surfaces 5312A, 5312B, 5312C, and 5312D also are configured as curved lateral surfaces of truncated right circular cones, all having the same taper angle, but the taper angle of mandrel adjustment surfaces 5312A, 5312B, 5312C, and 5312D is greater than the taper angle of mandrel contact surfaces 5311A, 5311B, 5311C, and 5311D.

[0170] Gripping assembly 5400 comprises a cage 5410 and a plurality of gripping elements 5420. Gripping assembly 5400 acts as a segmented collet assembly and each gripping element 5420 acts as a collet segment. FIGS. 16A and 16B, respectively, are side and front elevations of a representative gripping element 5420. Relative to axis 5001 of CRT 5000, each gripping element 5420 has a radially-intemal workpiece engagement surface 5224 and a radially-external profile defining:

[0171] • first gripping element contact surfaces 5421A, 5421B, 5421C, and 5421D;

[0172] • gripping element adjustment surfaces 5422A, 5422B, 5422C, and 5422D axially contiguous with first gripping element contact surfaces 5421A, 5421B, 5421C, and 5421D, respectively, and configured for sliding engagement with mandrel adjustment surfaces 5312A, 5312B, 5312C, and 5312D, respectively; and

[0173] • second gripping element contact surfaces 5423A, 5423B, 5423C, and 5423D axially contiguous with gripping element adjustment surfaces 5422A, 5422B, 5422C, and 5422D, respectively.

[0174] In this embodiment, first gripping element contact surfaces 5421A, 5421B, 5421C, and 5421D, and second gripping element contact surfaces 5423A, 5423B, 5423C, and 5423D, are configured as curved lateral surfaces of right circular cylinders with the axes of the right circular cylinders oriented to match the taper angle of mandrel contact surfaces 5311A, 5311B, 5311C, and 5311D according to US 11,167,358. Gripping element adjustment surfaces 5422A, 5422B, 5422C, and 5422D are configured as curved lateral surfaces of truncated right circular cones having taper angles equal to the taper angle of mandrel adjustment surfaces 5432A, 5432B, 5432C, and 5432D.

[0175] First gripping element contact surfaces 5421A, 5421B, 5421C, and 5421D define a first grip range of CRT 5000, and second gripping element contact surfaces 5423A, 5423B, 5423C, and 5423D define a second grip range of CRT 5000:

[0176] • FIG. 17 shows CRT 5000 gripping a first-size workpiece 5501 within the first grip range of CRT 5000. In the first grip range, first gripping element contact surfaces 5421A, 5421B, 5421C, and 5421D of each gripping element 5210 are in sliding engagement with mandrel contact surfaces 5311A, 5311B, 5311C, and 5311D, respectively.

[0177] • FIG. 18 shows CRT 5000 gripping a second-size workpiece 5502 within the second grip range of CRT 5000. In the second grip range, second gripping element contact surfaces 5213A, 5213B, 5213C, and 5213D of each gripping element 5210 is in sliding engagement with mandrel contact surfaces 5311 A, 531 IB, 5311C, and 531 ID, respectively.

[0178] The grip range of CRT 5000 is changed by moving gripping assembly 5400 axially relative to mandrel assembly 5300, with a corresponding change in the radial position of gripping elements 5420. Having reference to FIGS. 17 and 18, and considering mandrel assembly 5300 as a stationary reference, gripping assembly 5400 can be moved axially downward to transition from the first grip range to the second grip range, causing gripping element adjustment surfaces 5422A, 5422B, 5422C, and 5422D to slidingly engage mandrel adjustment surfaces 5312A, 5312B, 5312C and 5312D, respectively, and thereby urging radially-inward movement of gripping elements 5420 toward axis 5001. To change from the second grip range to the first grip range, gripping assembly 5400 can be moved axially upward relative to mandrel assembly 5300. Gripping elements 5420 may be urged radially outward relative to axis 5001 by any suitable means known to persons of ordinary skill in the art such as but not limited to one or more mechanical springs (not shown).

[0179] Although not specifically described or illustrated herein, variant embodiments of an internally-gripping CRT configurable to grip workpieces of two or more different sizes in accordance with the present disclosure can be readily configured by persons of ordinary skill in the art of internally-gripping and externally-gripping casing running tools, in light of the foregoing description of a non-limiting embodiment of an externally- gripping CRT configurable to grip workpieces of two different sizes and without going beyond the scope of the present disclosure.

[0180] # # # # #

[0181] It will be readily appreciated by persons skilled in the art that various modifications to embodiments in accordance with the present disclosure may be devised without departing from the scope of the present teachings, including modifications that use equivalent structures or materials hereafter conceived or developed. Persons of ordinary skill in the art will readily appreciate that collet mechanisms configurable to grip workpieces of more than three sizes may be devised according to the present teachings. It is especially to be understood that the scope of the present disclosure is not intended to be limited to described or illustrated embodiments, and that the substitution of a variant of any claimed or illustrated element or feature, without any substantial resultant change in functionality, will not constitute a departure from the scope of the disclosure.

[0182] In this patent document, any form of the word “comprise” is to be understood in its 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 such element or feature is present, unless the context clearly requires that there be one and only one such element or feature.

[0183] Any use herein of any form of the terms "connect", "engage", "couple", "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 include indirect interaction between the elements such as through secondary or intermediary structure.

[0184] Relational and conformational terms such as (but not limited to) “equal”, “axial”, “axisymmetric”, 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 equal”) unless the context clearly requires otherwise.

[0185] Wherever used in this document, the terms “typical” and “typically” are to be understood and interpreted in the sense of being representative of common usage or practice, and are not intended to be understood or interpreted as implying essentiality or invariability. LIST OF DRAWING ELEMENTS AND MATHEMATICAL SYMBOLS

[0186] Label Description

[0187] 100 prior art external collet mechanism

[0188] 110 first segmented collet assembly

[0189] 111 collet segment

[0190] 112 collet segment contact surface

[0191] 113 workpiece engagement surface

[0192] 120 second segmented collet assembly

[0193] 121 collet segment

[0194] 122 collet segment contact surface

[0195] 123 workpiece engagement surface

[0196] 190 collet receiver

[0197] 191 collet receiver contact surface

[0198] 199 longitudinal axis of collet receiver 190

[0199] 200 prior art external collet mechanism

[0200] 210 segmented collet assembly

[0201] 211 collet segment

[0202] 212 collet segment contact surface

[0203] 213 workpiece engagement surface

[0204] 290 collet receiver

[0205] 291 collet receiver contact surface

[0206] 299 longitudinal axis of collet receiver 290

[0207] 901 first-size workpiece

[0208] 902 second-size workpiece

[0209] 1000 external collet mechanism

[0210] 1100 collet receiver

[0211] 1101 receiver contact surface

[0212] 1102 receiver adjustment surface

[0213] 1109 longitudinal axis of collet receiver 1100

[0214] 1200 segmented collet assembly Label Description

[0215] 1210 collet segment

[0216] 1211 first collet segment contact surface

[0217] 1212 collet segment adjustment surface

[0218] 1213 second collet segment contact surface

[0219] 1214 workpiece engagement surface

[0220] 1301 first-size workpiece

[0221] 1302 second-size workpiece a taper angle of receiver adjustment surface e taper angle of receiver contact surfaces

[0222] 2000 internal collet mechanism

[0223] 2100 collet receiver

[0224] 2101 receiver contact surface

[0225] 2102 receiver adjustment surface

[0226] 2109 longitudinal axis of collet receiver 2100

[0227] 2200 segmented collet assembly

[0228] 2210 collet segment

[0229] 2211 first collet segment contact surface

[0230] 2212 collet segment adjustment surface

[0231] 2213 second collet segment contact surface

[0232] 2214 workpiece engagement surface

[0233] 2301 first-size workpiece

[0234] 2302 second-size workpiece

[0235] 3000 external collet mechanism for 3 sizes of workpiece

[0236] 3100 collet receiver

[0237] 3101 receiver contact surface

[0238] 3102 receiver adjustment surface

[0239] 3109 longitudinal axis of collet receiver 3100

[0240] 3200 segmented collet assembly

[0241] 3210 collet segment Label Description

[0242] 3211 first collet segment contact surface

[0243] 3212 first collet segment adjustment surface

[0244] 3213 second collet segment contact surface

[0245] 3214 second collet segment adjustment surface

[0246] 3215 third collet segment contact surface

[0247] 3216 workpiece engagement surface

[0248] 3301 first-size workpiece

[0249] 3302 second-size workpiece

[0250] 3303 third-size workpiece

[0251] 4000 external collet mechanism with stepped receiver

[0252] 4100 collet receiver

[0253] 4101 first receiver contact surface

[0254] 4102 receiver adjustment surface

[0255] 4103 second receiver contact surface

[0256] 4109 longitudinal axis of collet receiver 4100

[0257] 4200 segmented collet assembly

[0258] 4210 collet segment

[0259] 4211 collet segment contact surface

[0260] 4212 collet segment adjustment surface

[0261] 4213 workpiece engagement surface

[0262] 4301 first-size workpiece

[0263] 4302 second-size workpiece

[0264] 5000 externally gripping casing running tool (for 2 sizes of casing)

[0265] 5001 longitudinal axis of casing running tool 5000

[0266] 5100 axial extension linkage

[0267] 5110 drive cam body

[0268] 5120 intermediate cam body

[0269] 5130 driven cam body

[0270] 5140 latch mechanism

[0271] 5200 latch release mechanism Label Description

[0272] 5300 mandrel assembly

[0273] 5310 lower mandrel

[0274] 5311A, 5311B, mandrel contact surfaces

[0275] 5311C, 5311D

[0276] 5312A, 5312B, mandrel adjustment surfaces

[0277] 5312C, 5312D

[0278] 5319 longitudinal axis of lower mandrel 5310

[0279] 5320 upper mandrel

[0280] 5330 mandrel lock ring

[0281] 5400 gripping assembly

[0282] 5410 cage

[0283] 5420 gripping element

[0284] 5421A, 5421B, first gripping element contact surfaces

[0285] 5421C, 5421D

[0286] 5422A, 5422A, gripping element adjustment surfaces

[0287] 5422C, 5422D

[0288] 5423A, 5423B, second gripping element contact surfaces

[0289] 5423C, 5423D

[0290] 5424 workpiece engagement surface

[0291] 5501 first-size workpiece

[0292] 5502 second- size workpiece

Claims

EMBODIMENTS IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A collet mechanism configurable to grip workpieces of two or more different sizes, said collet mechanism comprising:(a) a collet receiver having a longitudinal receiver axis, and defining:• an axisymmetric receiver contact surface configured as a curved lateral surface of a first truncated right circular cone having a first taper angle relative to the receiver axis; and• an axisymmetric receiver adjustment surface contiguous with the receiver contact surface, and configured as a curved lateral surface of a second truncated right circular cone having a second taper angle relative to the receiver axis, said second taper angle being greater than the first taper angle; and(b) a segmented collet assembly comprising a plurality of collet segments, each collet segment defining:• a workpiece engagement surface configured for gripping an elongate workpiece;• two or more separate and longitudinally- aligned collet segment contact surfaces, each configured for longitudinally-sliding engagement with the receiver contact surface; and• one or more collet segment adjustment surfaces, each being disposed between and longitudinally contiguous with two of the two or more collet segment contact surfaces, and each being configured for longitudinally-sliding engagement with the receiver adjustment surface; such that the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the collet segment contact surfaces engaging the receiver contact surface.

2. The collet mechanism as in Claim 1 wherein the collet mechanism is configured for gripping an external surface of a workpiece.

3. The collet mechanism as in Claim 1 wherein the collet mechanism is configured for gripping an internal surface of a workpiece.

4. A collet mechanism as in any one of Claims 1-3 wherein at least one of the two or more collet segment contact surfaces is configured at least partly as a curved lateral surface of an oblique circular cylinder.

5. A collet mechanism as in any one of Claims 1-3 wherein at least one of the two or more collet segment contact surfaces is configured at least partly as a curved lateral surface of a right circular cylinder.

6. An externally-gripping tubular running tool configurable to grip workpieces of two or more different sizes, said tubular running tool having a longitudinal tool axis and comprising:(a) an elongate mandrel having a longitudinal mandrel axis colinear with the tool axis, and an inner bore defining:• one or more axisymmetric radially-inward-oriented mandrel contact surfaces, each configured as a curved lateral surface of a truncated circular cone having a first taper angle relative to the mandrel axis; and• for each of the one or more mandrel contact surfaces, an axisymmetric mandrel adjustment surface configured as a curved lateral surface of a truncated circular cone having a second taper angle relative to the mandrel axis, said second taper angle being greater than the first taper angle; and(b) a gripping assembly comprising a plurality of gripping elements, each gripping element having:• a radially-inward-oriented workpiece engagement surface configured for gripping engagement with an external surface of a tubular workpiece;• for each of the one or more mandrel contact surfaces, one or more pluralities of radially-outward-oriented gripping element contact surfaces, each defining two or more separate and longitudinally-aligned gripping element contact surface regions configured for longitudinally-sliding engagement with a corresponding one of the one or more mandrel contact surfaces; and• one or more gripping element adjustment surfaces, each being disposed between and longitudinally contiguous with two of the two or more gripping element contact surface regions, and each being configured for longitudinally- sliding engagement with a corresponding mandrel adjustment surface.

7. The externally-gripping tubular running tool as in Claim 6 wherein at least one of the two or more gripping element contact surfaces is configured at least partly as a curved lateral surface of an oblique circular cylinder.

8. The externally-gripping tubular running tool as in Claim 6 wherein at least one of the two or more gripping element contact surfaces is configured at least partly as a curved lateral surface of a right circular cylinder.

9. An internally-gripping tubular running tool configurable to grip workpieces of two or more different sizes, said tubular running tool having a longitudinal tool axis and comprising:(a) an elongate mandrel having a longitudinal mandrel axis colinear with the tool axis, and an outer mandrel surface defining:• one or more axisymmetric radially-outward-oriented mandrel contact surfaces, each configured as a curved surface of a truncated circular cone having a first taper angle relative to the mandrel axis; and• for each of the one or more mandrel contact surfaces, an axisymmetric mandrel adjustment surface configured as a curved lateral surface of a truncated circular cone having a second taper angle relative to the mandrel axis, said second taper angle being greater than the first taper angle; and(b) a gripping assembly comprising a plurality of gripping elements, each gripping element having:• a radially-outward-oriented workpiece engagement surface configured for gripping engagement with an internal surface of a tubular workpiece; and• one or more radially-inward-oriented gripping element contact surfaces, each defining two or more separate and longitudinally- aligned gripping element contact surface regions, each configured for longitudinally-sliding engagement with a corresponding one of the one or more mandrel contact surfaces; and• one or more gripping element adjustment surfaces, each being disposed between and longitudinally contiguous with two of the two or more gripping element contact surface regions, and each being configured for longitudinally- sliding engagement with a corresponding mandrel adjustment surface.

10. The internally- gripping tubular running tool as in Claim 9 wherein at least one of the two or more gripping element contact surfaces is configured at least partly as a curved lateral surface of an oblique circular cylinder.

11. The internally- gripping tubular running tool as in Claim 9 wherein at least one of the two or more gripping element contact surfaces is configured at least partly as a curved lateral surface of a right circular cylinder.

12. A collet mechanism configurable to grip workpieces of two or more different sizes, said collet mechanism comprising:(a) a collet receiver having a longitudinal receiver axis and defining, in longitudinal sequence:• a first axisymmetric receiver contact surface configured as a curved lateral surface of a first truncated right circular cone having a first taper angle relative to the receiver axis;• an axisymmetric receiver adjustment surface configured as a curved lateral surface of a second truncated right circular cone having a second taper angle relative to the receiver axis, said second taper anglebeing greater than the first taper angle, said receiver adjustment surface being longitudinally contiguous with the first receiver contact surface; and• a second axisymmetric receiver contact surface configured as a curved lateral surface of a third truncated right circular cone having the first taper angle, said second receiver contact surface being longitudinally contiguous with the receiver adjustment surface;(b) a segmented collet assembly comprising a plurality of collet segments, each defining:• a workpiece engagement surface configured for gripping an elongate workpiece;• a collet segment contact surface configured for longitudinally-sliding engagement with a user-selected one of the first and second receiver contact surfaces; and• a collet segment adjustment surface longitudinally-contiguous with the collet segment contact surface, and configured for longitudinally- sliding engagement with the receiver adjustment surface; such that the collet mechanism is configurable to grip workpieces of different sizes by axially repositioning the segmented collet assembly relative to the collet receiver to change the receiver contact surface engaged by the collet segment contact surface.

13. The collet mechanism as in Claim 12 wherein the collet mechanism is configured for gripping an external surface of a workpiece.

14. The collet mechanism as in Claim 12 wherein the collet mechanism is configured for gripping an internal surface of a workpiece.

15. The collet mechanism as in any one of Claims 12-14 wherein each collet segment contact surface is configured at least partly as a curved lateral surface of an oblique circular cylinder.

16. The collet mechanism as in any one of Claims 12-14 wherein each collet segment contact surface is configured at least partly as a curved lateral surface of a right circular cylinder.

Images