Bolsters for degradation picks

A bolster for a degradation pick includes a transverse cross section that is non-circular. Non-circular cross sections include square, triangular, hexagonal and other shapes. The bolster is made from a wear and/or erosion resistant material. The wear and/or erosion resistant material helps to protect the shank of the degradation pick. The bolster has a matching shape to the shape of the shank of the degradation pick.

BACKGROUND OF THE DISCLOSURE

Mining and material excavation is the process of breaking down material from a solid whole and removing the material. One method of excavation involves scraping a hardened pick against the surface of a material to remove the material. As the material is degraded, it may be conveyed or hauled away for processing or disposal. After removal of the material, more material may be eroded or scraped away, and the process repeated.

SUMMARY

In some embodiments, a bolster includes a transverse cross-sectional shape that is noncircular. In other embodiments, a bolster includes a transverse cross-sectional shape that is non-rotationally symmetrical about a central axis.

In yet other embodiments, a bolster includes a bolster body that has a bolster feature. The bolster is configured to connect to a pick body at an interface. The pick body has a transverse cross-sectional shape that includes at least one pick body feature. The bolster feature is similar to the pick body feature.

Additional features and advantages of embodiments of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of such embodiments. The features and advantages of such embodiments may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features will become more fully apparent from the following description and appended claims, or may be learned by the practice of such embodiments as set forth hereinafter.

DETAILED DESCRIPTION

This disclosure generally relates to devices, systems, and methods for bolsters used to protect degradation picks from wear during operation.FIG.1shows an embodiment of a road milling machine100of the type commonly used to engage and degrade asphalt or concrete to construct or resurface roads and other large surfaces. The road milling machine100may be supported and transported by continuous tracks101, wheels or other means known in the art. A rotatable drum102may be secured to an underside of the road milling machine100with a plurality of degradation picks attached to an exterior thereof. As the rotatable drum102is rotated, the degradation picks may repeatedly engage a surface upon which the road milling machine100is traveling.

FIG.2shows an embodiment of a mining machine200of the type commonly used to engage and degrade rock and other subterranean formations to extract valuable materials from the earth. The mining machine200may comprise a continuous chain203with a plurality of degradation picks204(shown in magnified view) secured thereto. Each of the degradation picks204may comprise a hardened tip206designed for repeated engagement with a tough material. Such repeated engagement may break up the tough material into aggregate pieces that may be removed. Each of the degradation picks204may also comprise a generally cylindrical shank opposite the hardened tip206that may be disposed within a bore within a block205that is rigidly fixed to the continuous chain203.

FIG.3shows an embodiment of a rotatable drum302secured to an underside of a road milling machine300. The road milling machine300may rotate the rotatable drum302around an axis generally parallel to a surface307upon which the road milling machine300may travel. The rotatable drum302may comprise a plurality of degradation picks304secured around an exterior thereof. As the rotatable drum302rotates, the degradation picks304may repeatedly impact the surface307which may comprise tough material of any variety such as asphalt or concrete. The repeated impact of degradation picks304against the surface307may allow the plurality of degradation picks304to degrade the surface307and break it into aggregate pieces.

FIG.4is a representation of a degradation pick404, according to at least one embodiment of the present disclosure. The degradation pick404may include a hardened tip406. The hardened tip406may be fabricated from an ultrahard material, such as polycrystalline diamond (PCD). As used herein, the term “ultrahard” is understood to refer to those materials known in the art to have a grain hardness of about 1,500 HV (Vickers hardness in kg/mm2) or greater. Such ultrahard materials can include but are not limited to diamond, sapphire, moissanite, hexagonal diamond (Lonsdaleite), cubic boron nitride (cBN), polycrystalline cBN (PcBN), Q-carbon, binderless PcBN, diamond-like carbon, boron suboxide, aluminum manganese boride, metal borides, boron carbon nitride, PCD (including, e.g., leached metal catalyst PCD, non-metal catalyst PCD, and binderless PCD or nanopolycrystalline diamond (NPD)) and other materials in the boron-nitrogen-carbon-oxygen system which have shown hardness values above 1,500 HV, as well as combinations of the above materials. In some embodiments, the ultrahard material may have a hardness values above 3,000 HV. In other embodiments, the ultrahard material may have a hardness value above 4,000 HV. In yet other embodiments, the ultrahard material may have a hardness value greater than 80 HRa (Rockwell hardness A).

The degradation pick404may include a pick body408. The pick body408may include an attachment end410. The attachment end410may be configured to attach to a rotatable drum (such as rotatable drum102ofFIG.1or rotatable drum302ofFIG.3). For example, in the embodiment shown, the attachment end410includes a threaded attachment. In this embodiment, the threaded attachment is inserted into a complementarily threaded bore of the rotating drum or a mounting block attached to the rotating drum (e.g., block205ofFIG.2). In other embodiments, the attachment end410may be attached to the rotatable drum using any other attachment mechanism, such as via braze, weld, friction fit, interference fit, retaining pin, retaining ring, and so forth.

As used herein, the term longitudinal is to be interpreted as parallel or approximately parallel to a longitudinal axis413the degradation pick404. As used herein, the term transverse is to be interpreted with respect to a width of the degradation pick404, or transverse to the longitudinal axis413.

The pick body408may include a shank412. In some embodiments, the shank412may be generally cylindrical. In other embodiments, the shank412may be non-cylindrical, or in other words, have a non-circular transverse cross-sectional shape. For example, in the embodiment shown, the shank412may have a hexagonal shape. Torque adjustment tools (e.g., wrench, socket) are designed to engage with an engagement feature of the pick body408with a specific shape in mind, such as a hexagon. Therefore, by making the shank412in the shape of the engagement feature, a similar shape and size torque adjustment tool may be used to install, tighten, loosen, and remove the degradation pick404. For example, the hexagonal shank412shown may be used with a hexagonal torque adjustment tool.

The pick body408may be fabricated from steel. In this manner, the pick body408may be installed and tightened on the rotating drum. Material removed by the hardened tip406may travel at high velocities, because the material is thrown by the degradation pick404as the rotating drum rotates, the material releases energy when fractured and the released energy accelerates the broken pieces away from the formation. Some of that broken material may hit, scrape, or otherwise engage the pick body408. This may erode and/or wear down the pick body408. In some embodiments, at least one feature of the shank412may be eroded and/or worn down such that the at least one feature is unrecognizable and/or useless. For example, the edges of a hexagonal shank412may be worn down such that a torque adjustment tool cannot engage the shank412.

A bolster414may be placed between the hardened tip406and the pick body408. In at least one embodiment, a body415of the bolster414may be fabricated from a wear and/or erosion resistant material, such as tungsten carbide (including cemented tungsten carbide cobalt (WCCo) and tungsten carbides with other metal additives such as nickel, titanium, vanadium, niobium, tantalum, chromium, etc.), cubic boron nitride, other carbides, other carbide matrix materials, abrasive resistant alloy steels (e.g., CPM steels (CPM is a trademark of Crucible Industries LLC); wear resistant steels, e.g., Stellite (Stellite is a trademark of Kennametal Inc.; e.g., cobalt-chromium alloys having high wear resistance), other wear and/or erosion resistant materials, or combinations of the foregoing. In other embodiments, the bolster414may be fabricated from an ultrahard material. As used herein, the term “ultrahard” is understood to refer to those materials known in the art to have a grain hardness of about 1,500 HV (Vickers hardness in kg/mm2) or greater. Such ultrahard materials can include but are not limited to diamond (including hexagonal diamond (Lonsdaleite), polycrystalline diamond (PCD) e.g., leached metal catalyst PCD, non-metal catalyst PCD, or binderless PCD or nanopolycrystalline diamond (NPD), etc.), sapphire, moissanite, cubic boron nitride (cBN) (including polycrystalline cBN (PcBN), binderless PcBN, etc.), Q-carbon, diamond-like carbon, boron suboxide, aluminum manganese boride, other metal borides, boron carbon nitride or other materials in the boron-nitrogen-carbon-oxygen system which have hardness values above 1,500 HV, as well as combinations of the above materials. In some embodiments, the ultrahard material may have a hardness values above 3,000 HV. In other embodiments, the ultrahard material may have a hardness value above 4,000 HV. In yet other embodiments, the ultrahard material may have a hardness value greater than 80 HRa (Rockwell hardness A).

In some embodiments, the bolster414may engage at least some of the broken material before it hits the pick body408, thereby at least partially protecting the pick body408. For example, at least some of the material broken by the hardened tip406may travel from the hardened tip406backwards towards the pick body408. By placing the bolster414between the hardened tip406and the pick body408, the bolster414may deflect at least some of this broken material so that it does not contact the pick body408. Because the bolster414is fabricated from a wear and/or erosion resistant material, the bolster414may help to reduce and/or eliminate wear on the pick body408, including reducing and/or eliminating wear on the shank412.

In at least one embodiment, one or more sections of the wear and/or erosion resistant material may be attached to the bolster body415. Wear and/or erosion resistant materials may be attached to the bolster body415using any attachment mechanism, including mechanical fasteners, braze, weld, press fit, interference fit, locking pin, snap ring, any other attachment mechanism, or combinations of the foregoing. The wear and/or erosion resistant materials may be attached to the bolster body415along a rotational axis of the rotatable drum to which the degradation pick404is attached. In this manner, the wear and/or erosion resistant materials may protect the shank412at the highest wear point. In other embodiments, the wear and/or erosion resistant materials may be attached to the bolster body415off the rotational axis of the rotatable drum.

In some embodiments, the hardened tip406may be brazed to the bolster body415at a bolster first end416. In some embodiments, a first bolster transverse cross-sectional shape at the bolster first end416may be complementary to a hardened tip transverse cross-sectional shape. For example, the hardened tip406may have a circular hardened tip transverse cross-sectional shape, and the bolster first end416may have a circular first bolster transverse cross-sectional shape. In other examples, the hardened tip406may have a non-circular cross-sectional shape, including triangular, square, pentagonal, hexagonal, septagonal, octagonal, a polygon with nine, ten, eleven, twelve, or more sides, non-polygonal shapes, and any other shape. In some embodiments, a hardened tip transverse cross-sectional area may be the same or about the same as a first bolster transverse cross-sectional area of the bolster body415at the bolster first end416. In other embodiments, the hardened tip transverse cross-sectional area may be greater than or less than the first bolster transverse cross-sectional area.

The bolster body415may include a bolster second end418opposite the first end416. In other words, the bolster first end416may be located distally from, or further away from the shank412, the bolster second end. The bolster414may be connected to the pick body408at an intersection420between the bolster second end418and the shank412. The shank412may include a shank transverse cross-sectional shape and the bolster body415may include a second bolster transverse cross-sectional shape at the bolster second end418. In at least one embodiment, the shank transverse cross-sectional shape and the second bolster transverse cross-sectional shape may be the same. For example, the shank transverse cross-sectional shape may be non-circular and the bolster transverse cross-sectional shape may be non-circular. Specifically, and in the embodiment shown, the second bolster transverse cross-sectional shape may be hexagonal, and the shank cross-sectional shape may be hexagonal. As discussed above, a hexagonal shanks412may be adjusted by a torque adjustment tool. By making the bolster body415have a hexagonal second bolster transverse cross-sectional shape, a torque adjustment tool may pass over the bolster414and onto the shank412. In this manner, the bolster body415may be erosion and/or wear resistant and protect the shank412, while the shank412may be ductile and tighten against a mounting block. In other examples, the second bolster transverse cross-sectional shape may be triangular, square, pentagonal, hexagonal, heptagonal, octagonal, polygonal of 9, 10, 11, 12, or more sides, ellipsoidal, curved with multiple concavities, non-polygonal including straight and curved sections, and any other non-circular shape. Different conditions, including material type, impact velocity, temperature, humidity, and so forth, may change the dynamics of material deflection by the bolster414, and therefore may change the optimal second bolster transverse cross-sectional shape.

For the purposes of this disclosure, rotationally symmetric may be interpreted to mean symmetric at each point around a central axis, such as a circle. Radially symmetric may be interpreted to mean symmetric at multiple even radial points around a circle, such as an ellipse, triangle, square, pentagon, any sided polygon, or any shape that includes regular features, cut-outs, and so forth along an edge. Non-rotationally symmetric may be interpreted to mean no symmetry at any two radial points about a circle, such as a circle with a bulge in it, a square with a protrusion out of only one side, or any other non-rotationally symmetric shape. In some embodiments, the second bolster transverse cross-sectional shape may be radially symmetric about a central axis with three, four, five, six, seven, eight, nine, ten, or more radial points of symmetry. In other embodiments, the second bolster transverse cross-sectional shape may be non-rotationally symmetrical. In still other embodiments, the second bolster transverse cross-sectional shape may have one, two, three, four, five, six, seven, eight, nine, ten, or more planes of symmetry that pass through the central axis. In other examples, the second bolster transverse cross-sectional shape may be non-symmetric, or have no planes of symmetry and no rotational or radial symmetry.

The shank412has a shank transverse cross-sectional area and the bolster body415has a second bolster transverse cross-sectional area at the bolster second end418. In some embodiments, the shank transverse cross-sectional area and the bolster transverse cross-sectional area may be the same or about the same. For example, in the embodiment shown inFIG.4, the shank transverse cross-sectional shape is hexagonal, and the second bolster transverse cross-sectional shape is hexagonal, and the shank transverse cross-sectional area is about the same as the second bolster transverse cross-sectional area. In this manner, a user may install the degradation pick404sliding a torque adjustment tool over the hardened tip406, the bolster414, and the shank412. The torque adjustment tool may then engage the shank412and/or the bolster414during installation of the degradation pick404. Therefore, shaping at least the bolster second end418to match the size and shape of the shank412may assist in installation and removal of the degradation pick404.

In other embodiments, the bolster second end418may have a different second bolster transverse cross-sectional shape than the shank transverse cross-sectional shape. For example, the second bolster transverse cross-sectional shape may be circular, and the shank transverse cross-sectional shape may be hexagonal. In other examples, the second bolster transverse cross-sectional shape may be hexagonal and the shank transverse cross-sectional shape may be circular.

In some embodiments, the bolster second end418may have a different second bolster transverse cross-sectional area than the shank transverse cross-sectional area. For example, the second bolster transverse cross-sectional area may be greater than or less than the shank transverse cross-sectional area.

In some embodiments, the first bolster transverse cross-sectional shape at the bolster first end416and the second bolster cross-sectional shape at the bolster second end418may be the same. In other embodiments, the first bolster transverse cross-sectional shape and the second bolster cross-sectional shape may be different. For example, the first bolster transverse cross-sectional shape may be circular, and the second bolster transverse cross-sectional shape may be hexagonal. In this manner, the bolster body415may have similar transverse cross-sectional shapes and/or areas to both the hardened tip406and the shank412. In other words, similar bolster transverse cross-sectional shapes and pick body cross-sectional shapes may include at least one feature, such as a protrusion, indentation, curved edge, straight edge, that is the same shape, size, thickness, width, or combinations of the foregoing. In at least one embodiment, similar features may be aligned on the bolster414and the shank412. In other embodiments, similar features may be misaligned on the bolster414and the shank412.

In some embodiments, the first bolster transverse cross-sectional area may be different from the second bolster transverse cross-sectional area. For example, the first bolster transverse cross-sectional area may be smaller than the second bolster transverse cross-sectional area.

If the first bolster transverse cross-sectional shape is different from the second bolster transverse cross-sectional shape and/or the first bolster transverse cross-sectional area is different from the second bolster transverse cross-sectional area, the bolster body415may include a transition region422between the bolster first end416and the bolster second end418. In some embodiments, the transition region422may extend from the bolster first end416to the bolster second end418. In other embodiments, the transition region422may extend from a point between the bolster first end416and the bolster second end418to the bolster second end418. In other embodiments, the transition region422may extend from the bolster first end416to a point between the bolster first end416and the bolster second end418. In yet other embodiments, the transition region422may extend between the bolster first end416and the bolster second end418without extending to either the bolster first end416or the bolster second end418.

In some embodiments, the transverse cross-sectional area of the bolster body415may change gradually in the transition region422between the bolster first end416and the bolster second end418. In other embodiments, the transverse cross-sectional area of the bolster body415may change suddenly at a point between the bolster first end416and the bolster second end418. For example, the transition region422may include one or more ledges or ribs between the bolster first end416and the bolster second end418.

In some embodiments, the bolster transverse cross-sectional shape may change gradually in the transition region422between the bolster first end416and the bolster second end418. For example, in the embodiment shown, as the bolster transverse cross-sectional area increases along the transition region422, the bolster transverse cross-sectional shape may begin to include the flat sections of the hexagonal second bolster cross-sectional shape. In other embodiments, the bolster transverse cross-sectional shape may change suddenly at a point between the bolster first end416and the bolster second end418.

FIG.5is an exploded view of a degradation pick504, according to at least one embodiment of the present disclosure. The degradation pick504may include at least some of the same features and characteristics as the degradation pick described in relation toFIG.4. A pick body508may include a bore524. The bore524may extend partially or completely through a shank512. A bolster514may include a protrusion526protruding from a bolster body515. The protrusion526may be configured to be inserted into the bore524, and the protrusion526brazed to the bore524. Thus, the bolster514may be brazed to the pick body508and the shank512. In some embodiments, the bolster514may be connected to the pick body508using a mechanical connection, such as a threaded connection, a locking feature, a pin, heat fit, press fit, interference fit, or other mechanical connection. In other embodiments, the bolster514may be brazed to the pick body508with a flat connection, or in other words, without a protrusion526and a bore524.

The pick body508may include an interface520where the pick body contacts the bolster body515. The interface520may include one or more pick body alignment features528. Matching bolster alignment features530may be located on the bolster body515. When the one or more pick body alignment features528are lined up with the bolster alignment features530, then the bolster body515may be oriented with respect to the pick body508. For example, in the embodiment shown, the shank512has a hexagonal shape, and the bolster body515has a hexagonal bolster second end518. When the one or more pick body alignment features528are aligned with the bolster alignment features530, then the flat sections of the shank512's hexagonal shape and the flat sections of the bolster second end518's hexagonal shape may be aligned. This may facilitate proper alignment and installation between the bolster514and the pick body508. In some embodiments, the pick body alignment features528may be indentations or protrusions at the interface520, and the bolster alignment features530may be matching protrusions or indentations at the bolster second end518or on the protrusion526.

The bolster body515has a bolster first end516. The bolster first end may include a hardened insert face532. A hardened insert506may be brazed to the hardened insert face532. In some embodiments, the hardened insert face532may be flat, and the hardened insert506may be brazed to the flat hardened insert face532.

FIG.6-1is a representation of a longitudinal cross-section of a degradation pick604, according to at least one embodiment of the present disclosure. The degradation pick604may include at least some of the same features and characteristics as the degradation picks described in relation toFIG.4andFIG.5. The degradation pick604may include a bolster614. The bolster614may include a bolster first end616opposite the bolster body from a bolster second end618. In other words, the bolster first end616may be located distally from the bolster second end618, or the bolster second end may be located proximal from the bolster first end616, relative to a pick body608. The degradation pick604may include a hardened tip606brazed to the bolster first end616of the bolster body615. The bolster body615may include a protrusion626at the bolster second end618that is inserted into a bore624of the pick body608. The bolster614may be brazed to the pick body608at the protrusion626and the bore624.

The bolster first end616and the bolster second end618may have a different bolster transverse cross-sectional area and/or bolster transverse cross-sectional shape. Somewhere between the bolster first end616and the bolster second end618, the bolster transverse cross-sectional area and/or the bolster transverse cross-sectional shape may be changed in a transition region622. In the embodiment shown, the transition region622is continuous or substantially continuous between the bolster first end616and the bolster second end618. In other words, the longitudinal cross-section of the bolster616may be continuous or substantially continuous between the bolster first end616and the bolster second end618. In other embodiments, the transition region622may be non-continuous. In other words, the transition region622may include one or more ledges, platforms, breaks, or ribs. The transition region may be symmetric along the axis or the transition region may be non-symmetric along the axis (e.g., ovoid).

In some embodiments, the bolster body615may be at least partially convex in the transition region622. In other words, a bolster longitudinal edge631in the transition region622may be fully or partially convex, or curve away from a longitudinal axis613. This may further help to deflect fractured material away from the pick body608. In other embodiments, the bolster614may be at least partially concave in the transition region622. In other words, the bolster longitudinal edge631in the transition region622may be fully or partially concave, or curve toward the longitudinal axis613. In some embodiments, the bolster longitudinal edge631may be tapered at least partially tapered. In other words, the bolster cross-sectional shape and/or bolster cross-sectional area may change gradually between the bolster first end616and the bolster second end618.

In some embodiments, the bolster first end616and one or more of the bolster second end618and a protrusion end634may be parallel. In other words, the bolster first end616may be flat on a first plane, and the bolster second end618may be on a second plane, and the first plane may be parallel to the second plane.

The bolster614has a bolster length633. The bolster length633may be in a range having an upper value and a lower value, or upper and lower values including any of 0.25 in. (0.64 cm), 0.50 in. (1.27 cm), 0.75 in. (1.91 cm), 1.0 in. (2.54 cm), 1.5 in. (3.81 cm), 2.0 in. (5.08 cm), 2.5 in. (6.35 cm), 3.0 in. (7.32 cm), or any value therebetween. For example, the bolster length633may be greater than 0.25 in. (0.64 cm). In other examples, the bolster length633may be less than 3.0 in. (7.32 cm). In yet other examples, the bolster length633may be any value in a range between 0.25 in. (0.64 cm) and 3.0 in. (7.32 cm). In at least one embodiment, it may be critical that the bolster length633is between 0.5 in. and 1.5 in. to provide sufficient protection to the shank612.

The degradation pick604has a bolster ratio. The bolster ratio may be the ratio of the bolster length633to the shank length635. The bolster ratio may be in a range having an upper value and a lower value, or upper and lower values including any of 1:10, 1:8, 1:6, 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 8:1, 10:1, or any value therebetween. For example, the bolster ratio may be greater than 1:10. In other examples, the bolster ratio may be less than 10:1. In yet other examples, the bolster ratio may be any value in a range between 1:10 and 10:1. In at least one embodiment, it may be critical that the bolster ratio is less than 1:1 so that the bolster614may sufficiently protect the shank612.

FIG.6-2is another representation of a longitudinal cross-section of a degradation pick604, according to at least one embodiment of the present disclosure. The degradation pick604may include at least some of the same features and characteristics as the degradation picks described in relation toFIG.4throughFIG.6-1. In some embodiments, the bolster first end616may not be parallel to the bolster second end618. In other words, the bolster first end616may be non-parallel to the bolster second end618. For example, the bolster first end616may be oriented at an angle relative to the bolster second end618. Changing the angle of the bolster first end616may change the orientation of the hardened tip606with respect to the pick longitudinal axis613. In some embodiments, changing the orientation of the hardened tip606with respect to the pick longitudinal axis613may change the orientation with which the hardened tip606engages the surface (e.g., the surface307ofFIG.3). This may increase the efficiency of the degradation pick604and/or increase the rate of material removal by the degradation pick604.

FIG.6-3is another representation of a longitudinal cross-section of a degradation pick604, according to at least one embodiment of the present disclosure. The degradation pick604may include at least some of the same features and characteristics as the degradation picks described in relation toFIG.4throughFIG.6-2. In some embodiments, at least a portion of the bolster614may overhang at least a portion of a pick body608. In other words, at least a portion of the bolster614may have a larger bolster diameter636than a shank diameter638of the shank612. In some embodiments, the bolster614may have a larger outer circumference than the shank612. In this manner, the bolster614may wear and/or erode a difference between the bolster diameter636and the shank diameter638before the pick body608begins to wear and/or erode. This may further protect the pick body608from wear and/or erosion. In this manner, the bolster614may be sized to wear for a lifetime, or a portion of a lifetime, of the degradation pick604such that the bolster614may be worn out when the degradation pick604is ready to be replaced.

In some embodiments, the entire bolster614may overlap the shank612. In other embodiments, a portion of the bolster614may have a bolster diameter636that is the same as the shank diameter638and a portion of the bolster614that has a bolster diameter636that is greater than the shank diameter638. For example, a hexagonal shank612may have six flat sides. The bolster second end618may include at least one side that is complementary to one flat side of the shank612and at least one side that overhangs the shank612. This may still allow for a tool, such as a socket, to pass over the bolster614and engage the shank612for installation of the degradation pick604.

FIG.7-1is a representation of a degradation pick704, according to at least one embodiment of the present disclosure. In some embodiments, the degradation pick704may be angled to present the hardened tip706to the material to be degraded at an angle different from the longitudinal axis. In some embodiments, the pick body708may be oriented with a pick body longitudinal axis that is different from an attachment longitudinal axis of the attachment end710. In the same or other embodiments, the connection720may be angled relative to the pick body longitudinal axis and/or the attachment longitudinal axis.

In some embodiments, the bolster first end716may be parallel to the bolster second end718. In other embodiments, the bolster first end716may be non-parallel to the bolster second end718.

The pick body708may include a bolster support741. The bolster support741may be located behind the bolster714and provide support for the bolster714during operation of the degradation pick704. During operation, the forces on the bolster714attached to an angled pick body708may be greater than on a non-angled pick body. The bolster support741may help to prevent the bolster from being dislodged or removed from the pick body708.

The bolster714may include a bolster extension743. The angled pick body708may expose more of the pick body708(such as the shank712) to material fractured during operation of the degradation pick704. A bolster extension743may extend the bolster714into the shank712, which may provide additional protection from fractured material.

FIG.7-2is a representation of the bolster714ofFIG.7-1, according to at least one embodiment of the present disclosure. The bolster714may include a bolster cap745. A protrusion726may protrude from the bottom of the bolster cap745. A bolster extension743may also extend from the bottom of the bolster cap745. The protrusion726may protrude from the side743A of the bolster extension743. The protrusion726may be configured to protrude into a bore of the pick body708. In this manner, the bolster714may be protected from being dislodged from a pick body by the protrusion726and the bolster support741. In this manner, the bolster714may further protect the pick body708from wear and/or erosion from material fractured by the degradation pick704. In some embodiments, the bolster body may be non-rotationally symmetric.

FIG.8-1throughFIG.16-2are representations of bolsters that may be installed on a pick body of a degradation pick. For example, the bolsters shown may include a protrusion (e.g., protrusion526ofFIG.5) protruding from the second end (e.g., second end518ofFIG.5) of a bolster. The protrusion may be inserted into a bore (e.g., bore524ofFIG.5) of a pick body (e.g., pick body508ofFIG.5). The bolsters shown may similarly include alignment features (e.g., alignment features528,530ofFIG.5) that may align the bolster with respect to the pick body. Each bolster may include one or more bolster features that may be similar to a pick body feature, such that a torque adjustment tool may slip over the bolster to adjust the torque of the degradation pick by engaging the pick body feature. The pick body may include a shank (e.g., shank512ofFIG.5) that may include the pick body feature. The bolsters may include a hardened tip (e.g., hardened tip506ofFIG.5) that may be secured to the bolster at the bolster first end (e.g., first end516ofFIG.5). The first end and the second end of the bolster may be parallel or non-parallel. The bolster may overlap the shank of the pick body.

FIG.8-1is a perspective view of a bolster814, according to at least one embodiment of the present disclosure.FIG.8-2is a transverse cross-sectional view of the bolster814ofFIG.8-1, taken at the bolster second end818. The bolster814may include at least some of the same features and characteristics as the bolsters described in relation toFIG.4throughFIG.7. In some embodiments, the bolster814may have a hexagonal shape at the bolster second end818.

In some embodiments, the bolster814may have a bolster longitudinal edge831that is straight. In other embodiments, the bolster814may have a bolster longitudinal edge831that is curved. For example, the bolster longitudinal edge831may be convex, meaning that the bolster longitudinal edge831extends outward from a center of the bolster814.

The bolster814may include at least one bolster feature840. The bolster feature840may be any identifiable feature, such as a straight edge, a point, a bulge, an indentation, or any other identifiable feature. In the embodiment shown, the bolster814includes at least twelve bolster features840: six straight transverse edges842and six points844. The bolster feature840may be similar to at least one pick body feature, such as the edges and points of a hexagonal shank (e.g., shank412ofFIG.4). For example, the bolster feature840may be a straight edge, and the pick body feature may be a straight edge of the same length. In another example, the bolster feature840may be a protrusion, and the pick body feature may be a protrusion with the same length, shape, and curvature. Because of the bolster feature840, the bolster814may be non-circular. In the embodiment shown, the bolster814is radially symmetric at six points about a longitudinal axis.

In at least one embodiment, the one or more bolster features840may be similar to a pick body feature on the shank of a pick body (e.g., shank412on the pick body408ofFIG.4). For example, the pick body feature may be an engagement feature for a torque adjustment tool to engage and adjust the torque of the pick body. The one or more bolster features840may be complementary to the pick body feature such that the torque adjustment tool may slip over the bolster814to engage the engagement feature. The one or more bolster features840may be the same size, shape, width, length, thickness, or combinations of the foregoing, as the pick body feature. For example, the one or more bolster features840may be the same shape and size as the pick body feature. In at least one embodiment, the one or more bolster features840may be the same shape, but not the same size as the pick body feature. In the same or other embodiments, the one or more bolster features840may be aligned with the pick body feature. In other embodiments, the one or more bolster features840may be misaligned with the pick body feature.

FIG.9-1is a perspective view of a bolster914, according to at least one embodiment of the present disclosure.FIG.9-2is a transverse cross-sectional view of the bolster914ofFIG.9-1, taken near the bolster second end918. The bolster914may include at least some of the same features and characteristics as the bolsters described in relation toFIG.4throughFIG.8-2. In some embodiments, the bolster914may have a hexagonal shape at the bolster second end918. In other words, a bolster second transverse cross-sectional shape may be hexagonal. In some embodiments, a transverse cross-section taken at the bolster second end918may be hexagonal with substantially straight transverse edges942. In the same or other embodiments, a transverse cross-section taken between the bolster second end918and the bolster first end916may have one or more curved transverse edges942, as shown inFIG.9-2. In the embodiment shown, the bolster914is radially symmetric at six points about a longitudinal axis.

In some embodiments, the transverse edge942may be concave. In other words, the transverse edge942may bulge or curve inward toward the center of the bolster914. The concavity of the second bolster transverse cross-sectional shape may adjust the path taken by material that is deflected by the bolster914away from a pick body.

In some embodiments, the bolster914may have a bolster longitudinal edge931that is straight. In other embodiments, the bolster914may have a bolster longitudinal edge931that is curved. For example, the bolster longitudinal edge931may be concave, meaning that the bolster longitudinal edge931extends inward toward a center of the bolster914.

FIG.10-1is a perspective view of a bolster1014, according to at least one embodiment of the present disclosure.FIG.10-2is a transverse cross-sectional view of the bolster1014ofFIG.10-1, taken at the bolster second end1018. In at least one embodiment, a transverse cross-section taken at the bolster second end1018may have one or more curved transverse edges1042, as shown inFIG.10-2.

In some embodiments, one or more of the transverse edges1042may be concave. In other words, one or more of the transverse edges1042may bulge or curve inward toward the center of the bolster1014. In some embodiments, the concave transverse edge1042may extend from the bolster first end1016or near the bolster first end1016to the bolster second end1018. In this manner, the bolster1014may resemble the head of a star head screw, or a star head nut. In the embodiment shown, the bolster1014is radially symmetric at six points about a longitudinal axis.

FIG.11-1is a perspective view of a bolster1114, according to at least one embodiment of the present disclosure.FIG.11-2is a transverse cross-sectional view of the bolster1114ofFIG.11-1, taken at the bolster second end1118. In at least one embodiment, a transverse cross-section taken at the bolster second end1118may have transverse edges1142-1,1142-2that are both curved and straight.

In the embodiment shown, the bolster1114may include a first transverse edge1142-1that is straight or approximately straight, and a second transverse edge1142-2that is curved outward, or convex with respect to the center of the bolster1114. In this manner, the bolster1114may be rectangular with two rounded short edges. Or, in other words, the bolster1114may be ellipsoid with straight edges.

In some embodiments, the first transverse edge1142-1may be curved. The first transverse edge1142-1may be curved in the same direction as the second transverse edge1142-2. For example, the first transverse edge1142-1and the second transverse edge1142-2may be curved outward, or convex. In other embodiments, the first transverse edge1142-1and the second transverse edge1142-2may have different concavities. For example, the first transverse edge1142-1may be concave, and the second transverse edge1142-2may be convex. In the embodiment shown, the bolster1114is radially symmetric at two points about a longitudinal axis.

FIG.12-1is a perspective view of a bolster1214, according to at least one embodiment of the present disclosure.FIG.12-2is a transverse cross-sectional view of the bolster1214ofFIG.12-1, taken at the bolster second end1218. In at least one embodiment, a transverse cross-section taken at the bolster second end1218may have transverse edges1242-1,1242-2that are both curved and straight.

In the embodiment shown, the bolster1214includes three straight transverse edges1242-1, each straight transverse edge1242-1being separated by one of three curved transverse edges1242-2. In this manner, the bolster1214may appear to be a triangle with the corners trimmed with a curved radius. In the embodiment shown, the bolster1214is radially symmetric at three points about a longitudinal axis.

FIG.13-1is a perspective view of a bolster1314, according to at least one embodiment of the present disclosure.FIG.13-2is a transverse cross-sectional view of the bolster1314ofFIG.13-1, taken at the bolster second end1318. In at least one embodiment, a transverse cross-section taken at the bolster second end1318may have transverse edges1342-1,1342-2that are straight.

The bolster1314may have a plurality of first transverse edges1342-1and a plurality of second transverse edges1342-2. In some embodiments, the first transverse edges1342-1may have a different length than the second transverse edges1342-2. For example, the first transverse edges1342-1may be longer than the second transverse edges1342-2. In the embodiment shown, four first transverse edges1342-1are separated by four second transverse edges1342-2. In this manner, the bolster1314may appear to be a square with the corners removed. In the embodiment shown, the bolster1314is radially symmetric at four points about a longitudinal axis.

FIG.14-1is a perspective view of a bolster1414, according to at least one embodiment of the present disclosure.FIG.14-2is a top down view of the bolster1414ofFIG.14-1. In at least one embodiment, the bolster1414may have edges1442that are planar.

In some embodiments, the plurality of edges1442may be planar or approximately planar. In other embodiments, the plurality of edges1442may change from straight or planar at the bolster second end1416to curved at the bolster first end1418. One or more of the edges1442may include a cut-out1446. In some embodiments, the cut-out1446may extend from the bolster first end1416to the bolster second end1418. In the embodiment shown, the bolster1414may include four edges1442having four cut-outs taken at or near a corner of each edge. In the embodiment shown, the bolster1414is radially symmetric at four points about a longitudinal axis.

FIG.15-1is a perspective view of a bolster1514, according to at least one embodiment of the present disclosure.FIG.15-2is a top down view of the bolster1514ofFIG.15-1. In at least one embodiment, the bolster1514may have edges1542that are planar.

In some embodiments, the plurality of edges1542may be planar or approximately planar. In other embodiments, the plurality of edges1542may change from straight or planar at the bolster second end1516to curved at the bolster first end1518. One or more of the edges1542may include a cut-out1546. In some embodiments, the cut-out1546may extend from the bolster first end1516to the bolster second end1518. In the embodiment shown, the bolster1514may include five transverse edges1542having five cut-outs taken at or near a corner of each edge. In the embodiment shown, the bolster1514is radially symmetric at five points about a longitudinal axis.

FIG.16-1is a perspective view of a bolster1614, according to at least one embodiment of the present disclosure.FIG.16-2is a top down view of the bolster1614ofFIG.16-1. In at least one embodiment, the bolster1614may have edges (collectively1642) that are curved, with different edges1642having different radii of curvature and/or different concavity.

In the embodiment shown, the bolster1614has a first edge1642-1with a large radius of curvature and a second edge1642-2with a smaller radius of curvature. In this manner, the bolster1614may appear to have a bulge or a point at the second edge1642-2. In some embodiments, the bolster1614may include edges having short lengths, long lengths, large radii of curvature, small radii of curvature, or any combination of the foregoing, in any order around an outer circumference of the bolster1614. In the embodiment shown, the bolster1614is non-rotationally symmetric. The side surfaces or longitudinal surfaces between the first and second edges are shown as including a concave curve, however, in this and in other embodiments described above, the side surfaces between the edges may be at least partially straight (e.g., a straight line connects the two radiused edges) or the side surfaces between the edges may include a convex curve (e.g., the line connecting the two radiused edges may be entirely convex). That is, in some embodiments, the side surfaces can be partially concave, entirely concave, entirely straight, partially straight, partially convex, or entirely convex, or combinations of partially concave, partially straight, and/or partially convex.

The present disclosure may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are to be considered as illustrative and not restrictive. Changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.