power tong operator texas free sample

Power tongs are machines that may be used to make-up and break-out threaded connections between adjacent tubular segments by gripping and rotating a first tubular segment relative to a second tubular segment to either make-up or break-out the threaded connection between the two tubular segments. FIG. 1 is a perspective view of an example of an externally gripping power tong 100. The power tong 100 includes a drive motor 110 that may be hydraulically, electrically, and/or pneumatically-powered, and a gripping assembly mechanically coupled to the motor 110 for gripping and rotating a tubular segment received within a bay 106. A generally “C”-shaped gear housing 112 supports a pair of pivoting doors 114. The doors 114 may be closed to secure the bay 106 or swung open (as indicated in FIG. 1) to provide access to the bay 106. The bay 106 is generally surrounded by the gear housing 112. The center of the bay 106 is between a pair of generally opposed pivotable gripping jaws 120, each having a generally arcuate gripping surface disposed radially inwardly toward the center of the bay 119.

Makeup requirements for tubular connections require high torque, such as in the order of thousands, and up to tens of thousands, of ft-lb torque. The components of a power tong must be capable of producing and sustaining the torques required to rotate tubular segments. As such, safely and effectively handling tubular members within an oilfield environment remains a priority to increase the efficiency and effectiveness of such tubular handling equipment.

FIGS. 2A-2C show multiple views of a power tong assembly used to grip and rotate a tubular segment in accordance with one or more embodiments of the present disclosure;

FIGS. 5A and 5B show multiple schematic views of a simplified hydraulic circuit for a power tong assembly in accordance with one or more embodiments of the present disclosure.

In accordance with various aspects disclosed herein, the present disclosure relates to a power tong assembly that may be used to make-up, break-out, and/or torque two or more tubular members, such as within an oilfield exploration and production operation environment discussed above. The power tong assembly includes a power tong is configured to grip and rotate a tubular segment in a first direction, such as to make-up a threaded connection with the tubular segment, and in a second direction, such as to break-out the threaded connection with the tubular segment. The power tong assembly further includes an interlock system operably coupled to the power tong, in which the interlock system may be configured to selectively allow the power tong to rotate the tubular segment in one of the first direction and the second direction while preventing the power tong to rotate the tubular segment in the other of the first direction and the second direction. The interlock system may, additionally or alternatively, be configured to selectively allow the power tong to rotate or not rotate in response to conditions that are sensed by the interlock system.

For example, the power tong may be operated in two directions, such as a make-up direction (e.g., operated in a make-up setting) and a break-out direction (e.g., operated in a break-out setting), in which the make-up setting enables the power tong to rotate a tubular segment in the first direction to make-up a threaded connection with the tubular segment, and the break-out setting enables the power tong to rotate the tubular segment in the second direction to break-out the threaded connection with the tubular segment. Further, the interlock system includes a make-up setting that allows the power tong to rotate the tubular segment in the first direction to make-up the threaded connection with the tubular segment and a break-out setting that allows the power tong to rotate the tubular segment in the second direction to break-out the threaded connection with the tubular segment. As such, the interlock system is configured to prevent the power tong to operate in the make-up setting when the interlock system is in the break-out setting, and further is configured to prevent the power tong to operate in the break-out setting when the interlock system is in the make-up setting.

In one or more embodiments, the power tong may include a high-speed setting to rotate the tubular segment in the first direction and the second direction in a high gear and a low-speed setting to rotate the tubular segment in the first direction and the second direction in a low gear. Accordingly, in one embodiment, the interlock system is configured to allow the power tong to operate in the make-up setting and the high-speed setting only when the interlock system is in the make-up setting, and is configured to allow the power tong to operate in the break-out setting and the high-speed setting only when the interlock system is in the break-out setting. The interlock system may further include a selector mechanism, such as a plug assembly or a three-way valve, which enables the interlock system to move between the make-up setting and the break-out setting. Further, the interlock system may include a power tong gear position sensor. The power tong gear position sensor may be used to sense and determine if the power tong is configured to operate in high gear (e.g., a high-speed setting) or operate in low gear (e.g., a low-speed setting). Accordingly, as discussed more below, the interlock system may use the selector mechanism and/or the power tong gear position sensor to sense the setting or mode of operation of the power tong, in which the interlock system may be configured to selectively allow the power tong to rotate or not rotate in response to conditions that are sensed by the selector mechanism and/or the power tong gear position sensor of the interlock system. Furthermore, the interlock system may be operably coupled to a bi-directional hydraulic motor of the power tong such that the interlock system disables the hydraulic motor to prevent the power tong to rotate the tubular segment in the other of the first direction and the second direction.

In one or more embodiments, the interlock system may include a selector mechanism, in which the selector mechanism may be used as a tong operator interface to switch and move the interlock system between the make-up setting and the break-out setting. In such an embodiment, if the selector mechanism is in the make-up setting (e.g., a make-up position) and the power tong is actuated in the make-up direction, the interlock system may permit the power tong to operate. In particular, the interlock system may permit the power tong to operate in the make-up direction in high-speed (e.g., the high-speed setting) and low-speed (e.g., the low-speed setting) if the selector mechanism of the interlock system is in the make-up position. Further, in such an embodiment, the interlock system may prevent or block the power tong to operate in the break-out direction in high-speed and only permit the power tong to operate in the break-out direction in low-speed if the selector mechanism of the interlock system is in the make-up position.

Further, if the selector mechanism is in the break-out setting (e.g., a break-out position) and the power tong is actuated in the break-out direction, the interlock system may permit the power tong to operate. In particular, the interlock system may permit the power tong to operate in the break-out direction in high-speed and low-speed if the selector mechanism of the interlock system is in the break-out position. Further, in such an embodiment, the interlock system may prevent or block the power tong to operate in the make-up direction in high-speed and only permit the power tong to operate in the make-up direction in low-speed if the selector mechanism of the interlock system is in the break-out position.

Referring now to FIGS. 2A, 2B, and 2C, multiple views of a power tong assembly 200 used to grip and rotate a tubular segment 202 in accordance with one or more embodiments of the present disclosure are shown. In particular, FIG. 2A shows a perspective view of the power tong assembly 200 when in use to make-up and/or break-out a threaded connection between a first upper tubular segment 202A and a second lower tubular segment 202B, FIG. 2B shows an above schematic view of the power tong assembly 200 when in use to make-up a threaded connection with the tubular segment 202, and FIG. 2C shows another above schematic view of the power tong assembly 200 when in use to break-out a threaded connection with the tubular segment 202.

In one or more embodiments, when making-up and breaking-out threaded connections between tubular segments, a mechanism or component is used to hold reaction torque on one tubular segment while the power tong is used to rotate the other tubular segment. One or more power tong assemblies may include with integral backup wrenches, in which the backup wrench may hold reaction torque on a tubular segment while the power tong makes-up and breaks-out threaded connections by rotating an adjacent tubular segment. In an embodiment in which a power tong assembly does not include an integral backup wrench, such as shown in FIG. 2A, reaction torque may be held on the lower tubular segment 202B using a drilling rotary 204 and/or other tubular gripping mechanism (e.g., a manual tong, a spider, a collar load support), while the power tong assembly 200 is used to rotate and apply torque to the upper tubular segment 202A.

As shown in FIGS. 2A-2C, a tong operator 206 may be in close proximity to the power tong assembly 200, such as particularly when making-up and breaking-out connections. For example, a power tong 208 of the power tong assembly 200 includes a make-up setting and a break-out setting, with the power tong 208 switchable between the make-up and break-out settings. In the make-up setting, the power tong 208 is used to rotate the upper tubular segment 202A in the first direction to make-up a threaded connection between the upper tubular segment 202A and the lower tubular segment 202B, and in the break-out setting, the power tong 208 is used to rotate the upper tubular segment 202A in the second direction to break-out the threaded connection between the upper tubular segment 202A and the lower tubular segment 202B. Furthermore, the power tong 208 may include a high-speed setting and a low-speed setting, with the power tong 208 switchable between the high-speed and low-speed settings. In the high-speed setting, the power tong 208 is used to rotate the upper tubular segment 202A in the first direction or in the second direction in a high gear. In the low-speed setting, the power tong 208 is used to rotate the upper tubular segment 202A in the first direction or in the second direction in a low gear. Accordingly, the tong operator 206 may operate and switch the power tong 206 between each of these different settings.

FIG. 2B shows an example of the power tong 208 when in the make-up setting, in which the power tong 208 is used in this embodiment to rotate the tubular segment 202A in a first direction (e.g., clockwise direction) when making-up threaded connections with the tubular segment 202A. As the power tong 208 rotates the tubular segment 202A in the clockwise direction, the power tong 208 will have the tendency to move and rotate from a reactive torque 210A in the counter-clockwise direction. In one or more embodiments, to prevent movement and rotation of the power tong 208, a snub line 212A may be attached to the power tong 208 in a direction opposite to the reactive torque 210A to prevent movement of the power tong 208 in response to the reactive torque 210A. As such, the snub line 212A may be used in the orientation shown to prevent rotation of the power tong 208 when making-up threaded connections with the tubular segment 202A.

Similarly, FIG. 2C shows an example of the power tong 208 when in the break-out setting, in which the power tong 208 is used in this embodiment to rotate the tubular segment 202A in a second direction (e.g., counter-clockwise direction) when breaking-out threaded connections with the tubular segment 202A. As the power tong 208 rotates the tubular segment 202A in the counter-clockwise direction, the power tong 208 will have the tendency to move and rotate from a reactive torque 210B in the clockwise direction as well. In one or more embodiments, to prevent movement and rotation of the power tong 208, a snub line 212B may be attached to the power tong 208 in a direction opposite to the reactive torque 210A. As such, the snub line 212B may be used to prevent rotation of the power tong 208 when breaking-out threaded connections with the tubular segment 202A.

As shown in FIGS. 2B and 2C, the direction of the attachment of the snub line 212 to the power tong 208 depends on if the power tong 208 is in the make-up setting or the break-out setting. However, as the power tong 208 may not include an integral backup wrench, and is shown to only include the rotary 204 to hold reaction torque, the power tong 208 may present a risk to the tong operator 206. In particular, in the embodiment shown in FIG. 2B, if the tong operator 206 switches the power tong 208 to operate in the break-out setting instead of the make-up setting, the snub line 212A will be ineffective in preventing rotation of the power tong 208. This will allow the power tong 208 to rotate and spin around the tubular segment 202A in the clockwise direction and strike the tong operator 206. This inefficiency is even further magnified if the tong operator 206 is operating the power tong 208 in the high-speed setting, as opposed to the low-speed setting. Similarly, in the embodiment shown in FIG. 2C, if the tong operator 206 switches the power tong 208 to operate in the make-up setting instead of the break-out setting, the snub line 212B will be ineffective in preventing rotation of the power tong 208. This will allow the power tong 208 to rotate and spin around the tubular segment 202A in the counter-clockwise direction and strike the tong operator 206.

Though not shown, the tong operator 206 often operates the power tong 208 from scaffolding or within confined spaces, in which the power tong 208 may then knock the tong operator 206 from the scaffolding and/or smash the tong operator 206 against the structure of a drilling rig, both of which are life-threatening injuries to the tong operator 206. Accordingly, the present disclosure relates to a power tong assembly, in which the power tong assembly includes a power tong and includes an interlock system operably coupled to the power tong, in which the interlock system is configured to selectively allow the power tong to rotate the tubular segment in one of the first direction and the second direction while preventing the power tong to rotate the tubular segment in the other of the first direction and the second direction.

As discussed above, the power tong 208 includes a make-up setting and a break-out setting, which may be operated through one or more handles or levers included with the power tong 208. The make-up setting enables the power tong 208 to rotate the tubular segment 202A in the first direction to make-up a threaded connection with the tubular segment 202A, and the break-out setting enables the power tong 208 to rotate the tubular segment 202A in the second direction to break-out the threaded connection with the tubular segment 202A.

Accordingly, an interlock system in accordance with the present disclosure that is operably coupled to the power tong 208 also includes a make-up setting and a break-out setting, in which the interlock system may be operated using a selector mechanism included within the interlock system. The make-up setting of the interlock system allows the power tong 208 to rotate the tubular segment 202A in the first direction, such as in both the high-speed setting and the low-speed setting, to make-up the threaded connection with the tubular segment 202A, and the break-out setting of the interlock system allows the power tong 208 to rotate the tubular segment 202A in the second direction, such as in both the high-speed setting and the low-speed setting, to break-out the threaded connection with the tubular segment 202A. FIG. 3A shows a flow chart of operation of a power tong assembly in accordance with the present disclosure. As shown, the interlock system may be set in either an interlock system make-up setting 302A or an interlock system break-out setting 302B. When in the interlock system make-up setting 302A, the power tong is enabled/allowed to operate in a power tong make-up setting 304A and is disabled/prevented to operate in a power tong break-out setting 304B. When in the interlock system break-out setting 302B, the power tong is disabled/prevented to operate in a power tong make-up setting 304C and is enabled/allowed to operate in a power tong break-out setting 304D.

As such, with reference to FIGS. 2A-2C, the interlock system is configured to prevent the power tong 208 to operate in the make-up setting when the interlock system is in the break-out setting, and further is configured to prevent the power tong 208 to operate in the break-out setting when the interlock system is in the make-up setting. Such a configuration may provide an additional safety feature to the power tong assembly 200, thereby helping prevent the tong operator 206 from unintentionally making-up and/or breaking-out of threaded connections that may lead to accidents within a drilling environment.

Further, as also discussed above, the power tong 208 may include a high-speed setting and a low-speed setting, which may be operated through one or more handles or levers included with the power tong 208. The high-speed setting enables the power tong 208 to rotate the tubular segment 202A in the first direction and/or the second direction in a high gear, and the low-speed setting enables the power tong 208 to rotate the tubular segment 202A in the first direction and/or the second direction in a low gear.

Accordingly, an interlock system in accordance with the present disclosure may be configured to allow the power tong 208 to operate in the make-up setting and the high-speed setting only when the interlock system is in the make-up setting, and may further be configured to allow the power tong 208 to operate in the break-out setting and the high-speed setting only when the interlock system is in the break-out setting.

FIG. 3B shows a flow chart of operation of a power tong assembly with an interlock system in a make-up setting in accordance with the present disclosure. The interlock system may be set in an interlock system make-up setting 306A, and the power tong may be set in either a power tong high-speed setting 308A or a power tong low-speed setting 308B. When in the interlock system make-up setting 306A and the power tong high-speed setting 308A, the power tong is enabled/allowed to operate in a power tong make-up setting 310A and is disabled/prevented to operate in a power tong break-out setting 310B. When in the interlock system make-up setting 306A and the power tong low-speed setting 308B, the power tong is enabled/allowed to operate in a power tong make-up setting 310C and is also enabled/allowed to operate in a power tong break-out setting 310D.

Further, FIG. 3C shows a flow chart of operation of a power tong assembly with an interlock system in a break-out setting in accordance with the present disclosure. The interlock system may be set in an interlock system break-out setting 306B, and the power tong may be set in either a power tong high-speed setting 308C or a power tong low-speed setting 308D. When in the interlock system break-out setting 306B and the power tong high-speed setting 308C, the power tong is disabled/prevented to operate in a power tong make-up setting 310E and is enabled/allowed to operate in a power tong break-out setting 310F. When in the interlock system break-out setting 306B and the power tong low-speed setting 308D, the power tong is enabled/allowed to operate in a power tong make-up setting 310G and is also enabled/allowed to operate in a power tong break-out setting 310H.

FIG. 3D shows a flow chart of operation of a power tong assembly in accordance with the present disclosure. In one or more embodiments, the interlock system may include a selector mechanism 312, in which the selector mechanism 312 may be used as a tong operator interface to switch and move the interlock system between operating the power tong in a make-up direction 314 or a break-out direction 316. Further, the interlock system may include a power tong gear position sensor 318. The power tong gear position sensor 318 may be used to sense and determine if the power tong is configured to operate in high gear (e.g., a high-speed setting) or operate in low gear (e.g., a low-speed setting). If the selector mechanism 312 is in the make-up setting (e.g., a make-up position) and the power tong gear sensor 318 detects that the power tong is in high gear, the interlock system may permit the power tong to operate in the make-up direction in high gear 320A and prevent or block the power tong to operate in the break-out direction in high gear 320B. If the selector mechanism 312 is in the make-up setting and the power tong gear sensor 318 detects that the power tong is in low gear, the interlock system may permit the power tong to operate in the make-up direction in low gear 320C and permit the power tong to operate in the break-out direction in high gear 320D.

Further, If the selector mechanism 312 is in the break-out setting (e.g., a break-out position) and the power tong gear sensor 318 detects that the power tong is in high gear, the interlock system may prevent or block the power tong to operate in the make-up direction in high gear 320E and permit the power tong to operate in the break-out direction in high gear 320F. If the selector mechanism 312 is in the break-out setting and the power tong gear sensor 318 detects that the power tong is in low gear, the interlock system may permit the power tong to operate in the make-up direction in low gear 320G and permit the power tong to operate in the break-out direction in high gear 320H.

An interlock system in accordance with the present disclosure may have one or more different types of configurations. For example, as shown and discussed below, the interlock system may be hydraulically controlled, in which the interlock system may include one or more hydraulic components and/or actuators and may be used to selectively control hydraulic fluid flow through the power tong. In particular, the interlock system may be used to selectively provide and control a supply of hydraulic fluid to a hydraulic motor of the power tong. However, in another embodiment, the interlock system may additionally or alternatively be magnetically controlled, electrically controlled, mechanically controlled, and/or pneumatically controlled. Accordingly, the present disclosure contemplates other methods and configurations for an interlock system than only those discussed herein, and therefore the present disclosure should not be so limited.

Referring now to FIGS. 4A-4G, multiple views of a power tong assembly 400 in accordance with one or more embodiments of the present disclosure are shown. The power tong assembly 400 includes a power tong 402 used for gripping and rotating tubular segments, particularly for making-up and breaking-out threaded connections, and also includes an interlock system 410. The interlock system 410 is operably coupled to the power tong 402 to selectively allow the power tong to rotate the tubular segment in one of the make-up and the break-out direction while also preventing the power tong 402 from rotating the tubular segment in the other of the make-up and the break-out direction. Accordingly, in this embodiment, the interlock system 410, or at least portions or components thereof, are positioned upon and operably coupled to a motor 404 of the power tong 402. The motor 404 may be a bi-directional hydraulic motor, in which the interlock system 410 may be used to disable the motor 404, such as by limiting hydraulic fluid supply to the motor 404, to prevent the power tong 402 from rotating the tubular segment in an undesired direction or at an undesired speed.

Along with the motor 404, the power tong 402 may include one or more handles 406 to set the power tong 402 in the make-up setting or the break-out setting. For example, in FIG. 4A, one of the handles 406 may be moved to set the power tong 402 in either the make-up setting or the break-out setting, while the other of the handles 406 may be moved to operate a lift cylinder operably coupled to the power tong 402 to selectively raise and lower the power tong 402. The power tong 402 may further include a handle 408 (e.g., speed shifting shaft) to set the power tong 402 in the high-speed setting or the low-speed setting. For example, in FIG. 4A, the handle 408 may be moved in one direction to set the power tong 402 in the high-speed setting or may be moved in another direction to set the power tong 402 in the low-speed setting.

As the interlock system 410 may include multiple portions or components, the interlock system 410 is shown in this embodiment as including a manifold 412, which may be formed as one or more housings, and a speed detection mechanism 414 (e.g., power tong gear position sensor 318). FIG. 4B shows a detailed view of the manifold 412, and FIG. 4C shows a detailed view of the speed detection mechanism 414. The manifold 412 may be positioned on the motor 404 of the power tong 402 and may have hydraulic fluid pumped through the manifold 412. As such, the manifold 412 may include hydraulic logic elements to selectively divert hydraulic fluid flow therethrough, such as including one or more valves, plugs, and/or switches to selectively divert the flow through the manifold 412. In particular, in this embodiment, the manifold 412 may include therewith or therein a selector mechanism 416, a check valve, an orifice or a needle valve, and an unloader valve.

The selector mechanism 416 may be included within the interlock system 410, and may be used as a tong operator interface to switch and move the interlock system 410 between the make-up setting and the break-out setting. Examples of the selector mechanism 416 are shown in FIGS. 4D-4F. In FIGS. 4D and 4E, the selector mechanism 416 is shown as a plug assembly 418 that includes one or more plugs. The plugs of the plug assembly 418 may be rearranged and positioned within the manifold 412 to set the interlock system 410 in a make-up setting (e.g., high-speed make-up setting), as shown in FIG. 4D, or to set the interlock system 410 in a break-out setting (e.g., high-speed break-out setting), as shown in FIG. 4E. Alternatively, the selector mechanism 416 is shown as a three-way valve 420 in FIG. 4F, such as a three-way ball valve, in which the three-way valve 420 may be set and moved between the make-up setting and the break-out setting.

The speed detection mechanism 414 may be operably coupled to the handle 408 that shifts the power tong 402 between the high-speed setting and the low-speed setting. Accordingly, the speed detection mechanism 414 may be positioned adjacent the handle 408, such as positioned on the bottom of the power tong 402. In this embodiment, the speed detection mechanism 414 may include a cam-operated valve 422. FIG. 4G shows a cross-sectional view of the cam-operated valve 422. As such, the cam-operated valve 422 is activated and moved between an open position and a closed position based on movement of a camming rod 424. The camming rod 424 may be coupled to the handle 408, and therefore the camming rod 424 may move with the handle 408 when shifting the power tong 402 between the high-speed setting and the low-speed setting. Accordingly, the cam-operated valve 422 may detect the speed of the power tong 402, such as if the power tong 402 is in the high-speed setting or the low-speed setting, based upon the position and movement of the camming rod 424.

Referring now to FIGS. 5A and 5B, multiple schematic views of a simplified hydraulic circuit 500 for a power tong assembly in accordance with one or more embodiments of the present disclosure are shown. As shown in this embodiment, the hydraulic circuit 500 includes a hydraulic motor 502 (e.g., bi-directional hydraulic motor), such as the motor 404 shown in FIG. 4A, and a directional control valve 504 (e.g., four-way, three-position directional control valve) that controls fluid flow to the hydraulic motor 502. The directional control valve 504 may include or be operably coupled to the handles 406 of the power tong 402. As such, the directional control valve 504 may be used to control the direction of rotation of the hydraulic motor 502, and therefore may be used to move the power tong 402 between the make-up setting and the break-out setting. Hydraulic fluid may be provided along a pressure flow path 550 and flow through a motor inlet flow path 552 into the directional control valve 504. The directional control valve 504 may then be used to selectively flow the hydraulic fluid into either the A-side or the B-side of the hydraulic motor 502, depending on the desired rotation of the power tong 402. Hydraulic fluid may then return from the hydraulic motor 502 back into the directional control valve 504, in which hydraulic fluid may then be provided to a return flow path 556 through a motor outlet flow path 554.

The directional control valve 560, as shown in the embodiment in FIGS. 5A and 5B, may be opened from operation of either a directional control valve 564 or a directional control valve 566 fluidly coupled in parallel to the directional control valve 560 along the case drain flow path 562. The directional control valve 564 (e.g., two-way, two-position directional control valve) may include an interlock valve that is movable between the open and closed position based upon an open or closed position of a door of the power tong 402. If the door of the power tong 402 is opened, the directional control valve 564 may relieve pilot pressure to the directional control valve 560 along the case drain flow path 562, thereby opening the directional control valve 560 and preventing operation of the hydraulic motor 502.

The hydraulic circuit 500 may further include a directional control valve 576 (e.g., three-way, two-position directional control valve), which may be the cam-operated valve 422 of the speed detection mechanism 414 shown in FIGS. 4A, 4C, and 4G. The directional control valve 576 may be movable between the open and closed position based upon if the power tong 402 is in the high-speed setting and the low-speed setting. As such, in this embodiment, the directional control valve 576 may be in the open position when the power tong 402 is in the high-speed setting, thereby fluidly coupling the pilot flow path 574 to the pilot flow path 568. Further, as shown in FIGS. 5A and 5B, the directional control valve 576 may be in the closed position when the power tong 402 is in the low-speed setting, thereby preventing fluid from flowing from the pilot flow path 574 to the pilot flow path 568. Furthermore, the hydraulic circuit 500 may include a check valve 578 and an orifice or a needle valve 580. The check valve 578 and the needle valve 580 may be in parallel with each other, as shown, and may be fluidly coupled to the pilot flow path 574 or the pilot flow path 568.

In operation, the selector mechanism 570 may be used to either allow fluid flow through the A-side motor flow path 572A or the B-side motor flow path 572B and into the pilot flow path 574. When the A-side motor flow path 572A is open with fluid allowed to flow therethrough, the A-side of the hydraulic motor 502 is not operational. For example, hydraulic fluid may be provided along the motor inlet flow path 552, into the directional control valve 504, and towards the A-side of the hydraulic motor 502. As the A-side motor flow path 572A is open, hydraulic fluid will flow into the A-side motor flow path 572A and continue along the pilot flow path 574. If the directional control valve 576 is present and open (e.g., the power tong 402 is in the high-speed setting), hydraulic fluid may flow from the pilot flow path 574 to the pilot flow path 568 to provide pilot pressure to the directional control valve 566. When pilot pressure is received along the pilot flow path 568 to the directional control valve 566, the directional control valve 566 will open, thereby relieving pilot pressure to the directional control valve 560 along the case drain flow path 562, opening the directional control valve 560, and preventing operation of the hydraulic motor 502.

In an embodiment in which hydraulic fluid received through the A-side of the hydraulic motor 502 causes the power tong 402 to make-up threaded connections with a tubular segment, the right side of the directional control valve 504 may be used as the make-up setting for the power tong 402, and the opening the B-side motor flow path 572B may be used as the make-up setting for the selector mechanism 570 (e.g., selector mechanism 416). In such an embodiment, the hydraulic motor 570 may, thus, be disabled when the directional control valve 504 is switched to the left side for the break-out setting of the power tong 402, thereby disabling and preventing the hydraulic motor 570, and the power tong 402, from operating in the break-out setting when the interlock system 410 is in the make-up setting.

Similarly, in an embodiment in which hydraulic fluid received through the B-side of the hydraulic motor 502 causes the power tong 402 to break-out threaded connections with a tubular segment, the left side of the directional control valve 504 may be used as the break-out setting for the power tong 402, and the opening the A-side motor flow path 572A may be used as the break-out setting for the selector mechanism 570 (e.g., selector mechanism 416). In such an embodiment, the hydraulic motor 570 may, thus, be disabled when the directional control valve 504 is switched to the right side for the make-up setting of the power tong 402, thereby disabling and preventing the hydraulic motor 570, and the power tong 402, from operating in the make-up setting when the interlock system 410 is in the break-out setting.

Further, as discussed above, the directional control valve 566 (e.g., unloader valve) may be used as a disabling portion within the interlock system to disable and prevent rotation of the power tong based a speed detection portion (e.g., a directional control valve 576 and/or a cam-operated valve 422) and the direction detection portion (e.g., selector mechanism 570). For example, when pilot pressure is received along the pilot flow path 568 to the directional control valve 566, the directional control valve 566 will open, thereby relieving pilot pressure to the directional control valve 560 along the case drain flow path 562. This enables the directional control valve 560 to open, in which hydraulic fluid then flows along the bypass flow path 558 instead of the motor inlet flow path 552, thereby disabling and preventing the hydraulic motor 502 from operation.

Accordingly, a power tong assembly including a power tong and an interlock system in accordance with the present disclosure may include one or more advantages, such as by decreasing the likelihood of an accident when operating a power tong. In particular, the interlock system is configured to selectively allow the power tong to rotate the tubular segment in one of the first direction and the second direction while preventing the power tong to rotate the tubular segment in the other of the first direction and the second direction. As such, the interlock system may be used to prevent the power tong from operating in a direction unintended by a tong operator, thereby preventing damage to the power tong, to the tubular segments handled by the power tong, and the tong operator.

Wedge-shaped pieces of metal with teeth or other gripping elements that are used to prevent pipe from slipping down into the hole or to hold pipe in place. Rotary slips fit around the drill pipe and wedge against the master bushing to support the pipe. Power slips are pneumatically or hydraulically actuated devices that allow the crew to dispense with the manual handling of slips when making a connection. Packers and other down hole equipment are secured in position by slips that engage the pipe by action directed at the surface.†

The large wrenches used for turning when making up or breaking out drill pipe, casing, tubing, or other pipe; variously called casing tongs, rotary tongs, and so forth according to the specific use. Power tongs are pneumatically or hydraulically operated tools that spin the pipe up and, in some instances, apply the final makeup torque.†

The present invention generally concerns tooling and equipment used in the maintenance and servicing of oil and gas production wells, and more particularly relates to a back-up tong of the type used in conjunction with a power tong to make or break threaded joints between successive tubing elements which make up the continuous tubing string extending through a well bore into the underground deposits.

Over the past several decades simple wrenches have been replaced by various types of tubing tongs. First by manually operated tongs and later by power tongs operated by a pneumatic or hydraulic power source. Power tongs apply torque to the upper tubing of the joint while a pipe wrench or other static restraining device serves as the back-up device to keep the bottom tubing of the joint from rotating. Each tong has to be anchored to a static part of the oil rig to keep the tong from turning with the tubing. More recently the back-up device has been suspended from the power tong, so that the reaction torque of one is cancelled by the other tong, eliminating the need to anchor the tongs to the oil rig. Instead, the tong unit is merely suspended by a hoist over the well bore. In such arrangements, the tail end of the back-up device attaches to a structural support on the back end of the power tong. A second structural support holds the back-up device parallel to the power tong. Current designs also feature a swivel and hinge mounting of the back-up device which allows the back-up device to be lowered away from the power tong to permit rotation of the backup device by 180 degrees in relation to the tubing being assembled. This allows the back-up device to be flipped over according to the direction of rotation of the power tong so as to provide appropriate reactive force to the torque of the power tong.

Power tongs are available in two configurations, "open head" and "closed head". The closed head type tong has a through bore in the tong unit which admits the tubing in an axial direction, but the tong housing fully encompasses the tubing in a radial direction. As each new tubing section to be added to the string is stabbed into the top end of the tubing string, it is inserted through the center bore of the power tong. The power tong is positioned to engage the new tube section, while the back-up device engages the top section of the tubing string extending from the well bore. The operator then actuates the power tong to make or break the connection, i.e. the threaded joint. The power tong is set up to rotate only in one direction, either clockwise or counter-clockwise. If rotation must be reversed, for example, from making up a string of tubing to disassembling the string, the power tong and back-up device are removed from the tubing connection area and the power tong is adjusted to perform the opposite rotation. The back-up device is turned upside down in order to react to the now reversed torque of the power tong on the tubing joint. The open head configuration of power tong is similar to the closed head except in that the body of the tong has a radially extending slot which permits the power tong to move away from the tubing connection after making or breaking that connection. In such case the backup device must have a similar ability to open and to move away from the tubing. This tong configuration allows more room for service personnel to work around the tubing.

Various types of power tongs are known which differ in the design of the tube gripping mechanism. One type of power tong was developed and sold by the Foster Cathead Company of

The Foster power tong was characterized by a ring gear mounted for rotation within a tong housing. The ring gear is toothed along both its inner and outer circumferences. A number of jaws inside the ring gear are pivoted to the housing. Each jaw has a radially outer arcuate toothed section in mesh with the ring gear and a radially inner jaw face grooved for gripping the surface of a tube positioned axially through the center of the ring gear. A drive gear powered by a hydraulic motor engages the outer circumference of the ring gear to turn the same. Rotation of the ring gear in one direction causes each of the jaws to pivot about its respective pivot point so as to swing the jaw faces towards the center of the ring gear and into gripping engagement with the tubing. Three or more such jaws engage the tubing in circumferentially spaced relationship. Further rotation of the ring gear in the same direction rotates the tubing along with the ring gear. This Foster-style gripping arrangement was subsequently adapted for use in a manually operated back-up tong. For this purpose, the ring gear was equipped with handles extending radially through the tong housing. Service personnel could manually turn the ring gear by means of these handles to engage or disengage the tong from the tubing.

While the Foster-style tongs work well for their intended purpose, no such tongs have been developed in an open head configuration to permit the back-up tong to separate from the tubing in a convenient manner so as to clear the work areas around the tubing when needed.

Power tongs have evolved to a considerable degree of refinement, while far less attention has been paid to improvement of back up tongs. These have remained relatively crude devices. The most commonly used back up device is the MS sold by the BJ Hughes (BJ Varco) Company. This back up has three links mounted at the end of a lever arm. The links wrap around a tube in a geometry such that the links tighten and grip the tube when torque is applied to the lever arm. This tong design is deficient in that the links contact a relatively small portion of the tube surface and tend to concentrate pressure so that at moderately high torque levels, 4,000 or 5,000 foot/lbs of torque, the tubing is indented by the links. Such deformation of the tubing away from its cylindrical shape may subsequently prevent passage of downhole tooling which is inserted through the tubing string to perform various maintenance and sampling operations at the well bottom. Other existing back-up tongs of open head configuration are equally problematic as they involve chains which must be wrapped around the tubing. In general, existing back up tongs of open head configuration require clumsy an time consuming handling. What is needed is a back-up tong of open head configuration which is quick and simple to operate, reliable, easy to maintain, and is effective at torques of up to 10,000 ft/lbs without damage to the tubing being assembled.

This invention addresses the aforementioned need by providing an open head Foster-style back-up tong for use in conjunction with a power tong to make or break threaded joints in strings of tubing. The novel back-up tong has a stem with an outer end for attachment to a supporting structure and an inner end, a tong housing supported at the inner end, a ring gear rotatable in the housing, a set of jaws pivoted to the housing and in mesh with the ring gear such that rotation of the gear in the housing is operative for pivoting the jaws between a retracted position and a gripping position. The back-up device according to this invention is characterized in that the annular continuity of the ring gear is interrupted by a gap which defines a radial aperture for admitting tubing into the center of the ring gear for engagement by the jaws. The gap may have a circumferential extent of less than one hundred twenty degrees of arc along the circumference of the ring gear. A radial slot may be defined in the housing, the gap in the ring gear being in alignment with the radial slot in an open position of said ring gear corresponding to the retracted position of the jaws. The ring gear is toothed along its interior circumference and is rotatably supported at its outer circumference between outer bearings mounted to the housing. Each of the jaws has a toothed end in mesh with the ring gear, an opposite end having a jaw face, and a pivot intermediate the toothed end and the opposite end. The housing has a pair of housing plates assembled in mutually parallel spaced apart relationship and the ring gear is contained between the plates. The housing plates may be held in spaced parallel relationship by bolts passing through corresponding spacer sleeves contained between the plates. The spacer sleeves may serve as the outer bearings around the ring gear. The housing is substantially open along all sides defined between the plates to discourage accumulation of debris in the housing and allow easy access for cleaning the housing interior. Each housing plate may be spaced from the ring gear to define therebetween a clearance space for further ease of removal of debris from between the ring gear and the plates. The clearance may be maintained by bolt heads of bolts inserted through the plates, the ring gear being axially supported between opposing sets of the bolt heads. Indexing holes in the jaws and the housing plates may be provided such that insertion of an alignment pin through the corresponding indexing holes positions the jaws in correct meshing engagement with the ring gear. A support assembly on the stem provides two degrees of freedom of movement of the tong relative to an external supporting structure. The tong is rotatable about a longitudinal axis of the stem, and is hinged along a hinge axis transverse to the stem axis at the support assembly for pendular movement to allow the tong head to swing down and away from an overlying supporting structure. One or more handles extend radially from the ring gear for use in application of manual torque to the ring gear. A fluid actuated drive element may be mounted to the tong housing and operatively connected for rotating the ring gear responsive to application of fluidic pressure to the drive element. The drive element may be a hydraulic actuator or a pneumatic actuator. Fluid conduits may be defined interiorly to the stem including an articulated fluidic coupling assembly containing internal conduits which remain in fluidic communication through a full range of relative positions of elements comprising the coupling assembly and the stem.

FIG. 1 is a perspective view of a typical prior art open head power tong combined with the novel open head back-up tong, with tubing captive in both tongs indicated in phantom lining;

FIG. 2 is a top plan view of an open head back-up tong according to this invention with the top plate of the housing removed to expose the tube gripping mechanism shown in open or retracted position;

FIG. 3 is a view taken as in FIG. 2 but showing the tong mechanism in gripping position engaging a typical tube passing through the center of the mechanism;

FIG. 5 is a fragmentary view as in FIG. 3 showing the optional use of a return spring between the ring gear and the housing to bias the tong mechanism to a normal retracted position, the mechanism being shown in locking position, and illustrating an alternate jaw insert for gripping smaller diameter tubing, the remaining jaws not shown in the figure having similar jaw inserts;

FIG. 7 shows the tail portion of the stem of the tong of FIG. 2 in longitudinal section and illustrates the combination hinge-swivel support of the stem and the articulated dual-axis fluidic coupling at the rear end of the stem;

With reference to the drawings, FIG. 1 shows a typical power tong/back-up tong combination generally designated by the numeral 10. The power tong 12 is of conventional design and has a through bore 14 in a tong head 16 which contains a hydraulically actuated tube gripping mechanism powered by hydraulic motor 18. The power tong is of open head configuration, having a radial slot 20 extending from the through bore 14 to the outside of the tong head. The slot 20 permits tubing T to be admitted laterally, i.e. in a radial direction, into the through bore 14. A hinged latch 22 closes the slot 20.

A back-up tong 40 according to the present invention is suspended underneath the power tong 12, and has a through bore axially aligned with the power tong through bore 14. A radial slot 56 opens the through bore 25 to the exterior of the back-up tong. The power tong 12 and back-up tong 40 are fixed by connecting structure against rotation relative to each other about their respective through bores. The unit 10 is positioned so that a joint in the tubing T is intermediate the power tong and the back-up tong. The back-up tong reacts against torque applied by the power tong to an upper tubing segment and transmitted to a lower tubing segment held in the back-up tong, so that the torques cancel each other within the structure of the unit 10.

Turning now to FIG. 2 the open head back-up tong according to this invention is generally designated by the numeral 40, . The back-up tong 40 includes a tong head housing 41 which comprises a bottom plate 42, and a similarly shaped top plate 44 partially seen only in FIGS. 4 and 6. The two plates 42, 44 are generally planar and are assembled in mutually parallel spaced apart relationship by means of spacer sleeves 46 held in compression between the two plates by through-bolts 48 and retaining nuts 49, as best understood from FIG. 4. In FIG. 2, the top plate 44 has been removed to expose the tube gripping tong mechanism housed between the two parallel plates. The spacer sleeves 46 are arranged in a circular pattern but at irregular spacing from each other. A ring gear 50 has an outer circumference 52 which makes sliding tangential contact with the spacer sleeves 46. The circumferential continuity of the ring gear 50 is interrupted by a gap defined between two opposite gear ends 54. The extent of the gap in the illustrated embodiment is substantially lesser than 90 degrees of arc, and spans a radial slot 56 defined in each of the two parallel plates 42, 44. The slot 56 has a semi-circular inner edge 58 which is concentric with the ring gear 50. The ring gear turns freely about its center in sliding contact with the sleeves 46. Three jaws 60 are mounted on pivots 64. Each jaw has a toothed end 66 which is in mesh with the toothed inner circumference 68 of the ring gear. The opposite end of each jaw 60 carries a jaw insert 70 which defines a circularly curved jaw face 72. Each insert 70 is removably secured to the jaw 60 by means of three bolts 74. The angular range of movement of the ring gear is limited by the sleeves 46 on either side of a pair of radially projecting handles 62. Each handle 62 extends beyond the edge of the plates 42, 44 such that the exterior portion of the handles can be securely gripped by hand for applying torque to the ring gear. A pair of forward handles 33 may be attached on either side of the slot opening 56 for use in aligning the tong 40 with a tubing string to be work on.

In one form of the invention illustrated in FIGS. 2 and 3, the back-up tong 40 is equipped with a fluid actuated drive cylinder 80 which may be either hydraulically or pneumatically actuated. The cylinder 80 is secured at pivot 82 to the parallel plates 42, 44. An actuating rod 84 extends from the opposite end of the cylinder and is pivotably connected at 86 to a radial stub 88 extending from the ring gear 50. A pair of flexible hoses 92a, 92b connect the driver cylinder 80 to corresponding port connections on the tong stem 94. As will be explained below, the tong stem has internal fluidic conduits for connecting the driver cylinder 80 to a hydraulic or pneumatic control system. Pressurized fluid supplied to the cylinder 80 through one of the hoses causes the rod 84 to extend from the cylinder, thus applying torque to the ring gear 50 in a clockwise direction in FIG. 2. The ring gear responds to the torque by rotating relative to the housing plates 42, 44 to a position illustrated in FIG. 3. As the ring gear rotates, it causes each of the jaws 60 to turn in a clockwise direction about their respective pivots 64, moving the jaws from a retracted position in FIG. 2 to a gripping position shown in FIG. 3. A tube T placed in the slot 56 of the tong head and positioned concentrically with the ring gear 50 is engaged at three circumferentially spaced locations by the three jaw faces 72. Engagement of the tube T by the three jaw faces 72 occurs before the handles 62 reach their respective limiting spacer sleeves 46, so that rotation of the ring gear is limited instead by resistance of the tube T against further inward pivotal movement of the three jaws 60. The radially inward pressure against the tube T results in a radially outer reactive force on the jaws which is largely absorbed by the pivots 64 and transmitted to the housing plates 42, 44.

The suspension block 108 also has two mutually parallel through-bores 122 of oval cross-section, seen in FIG. 7, which are perpendicular to the bolts 114. A suspension rod 124 passes through either one of the slots 122 and, as shown in FIG. 1, is supported between two skirt plates 24 affixed to the underside of the power tong 12 in the power tong/back-up tong combination unit 10. The tong head 41 is normally supported in generally horizontal position under the power tong on a removable support rod 26. The rod 124 provides a hinge mounting for the back-up tong 40, allowing the head end of the tong to swing down and away from the power tong after removal of the support rod 26. The suspension rod 124 is inserted through one or the other of the oval bores 122 so as to best level the back-up tong 40 under the power tong.

The suspension block 108 provides two degrees of freedom to the tong 40, i.e the entire tong 40 is free to turn about a longitudinal axis of the stem tail 104 relative to the suspension block 108. Furthermore, the suspension block 108 can pivot about the suspension rod 124 allowing the tong to swing through an arc in a vertical plane about a hinge axis transverse to the stem 94. The oval shape of the bores 122 allows the back-up tong 40 to be slightly adjusted in relation to the power tong as may be needed to properly engage the tubing T.

The swivel block 126 has a bore 140 which is closely sized to the outside diameter of the stem tail portion 104, and allows the fluidic coupling assembly 110 to swivel freely about the tong stem 94. Two annular grooves 142 in the stem tail 104 are axially aligned with corresponding annular grooves 144 in the bore 140 of the swivel block 126, defining annular conduits about the stem tail. The annular conduits are sealed from each other and the exterior environment by ring seals 146. Each bore 138 in the swivel block 126 opens into a corresponding one of the annular conduits 142 in the stem tail 104. In turn, each of the annular conduits 142 opens into a corresponding one of two longitudinal conduits 148 which run the length of the stem to the head end of the stem. Each hose 92a, 92b is connected to one of the conduits 148 at corresponding ports.

The back-up tong 40 is connected to a pressurized fluid pump and associated control valving 18 in FIG. 1 by means of external hoses, not shown in the drawings, connected to the two threaded ports 132 on the hinge body 128. One port 132 is connected to a source of pressurized fluid, at the high pressure side of a hydraulic or pneumatic pump, while the other port 132 is connected to the low pressure side of a hydraulic pump or vented to the atmosphere in the case of a pneumatic system, all through appropriate conventional control valving which enables service personnel to extend and retract the rod 84 of the drive cylinder 80 in order to open and close the jaws 60 of the tong by rotation of the ring gear 50 in one sense or the other. External hoses connected to the ports 132 are under little strain resulting from any movement of the tong 40 relative to the swivel block 126 and hinge body 128, as the latter two elements rotate about their corresponding axes to compensate for any movement of the stem 94, and do not transmit such movement to the connecting hoses.

In one form of the invention, the height of the ring gear 50 is substantially smaller than the spacing between the housing plates 42, 44 as shown in FIG. 6. A pair of wear bolts or spacer bolts 51 are inserted in opposing alignment through the plates 42, 44 with the head 53 of each bolt on the interior side of the corresponding plate and in overlying relationship to the ring gear 50. Each bolt is secured in place by an outer nut 55. The bolt heads 53 serve as spacers to support the ring gear 50 in evenly spaced relationship to the housing plates and to create therebetween clearance spaces 57 which discourage compaction of dirt and debris between the ring gear and the housing plates, and facilitate cleaning of the tong mechanism by flushing or brushing out such debris from the clearance spaces 57. Four pairs of upper and lower bolts 51 are provided about the circumference of the ring gear 50, as indicated in FIG. 2 where the lower bolt heads 53 between the ring gear 50 and lower plate 42 are shown in phantom lining.

The back up tong 40 can be constructed in a manually operated embodiment by eliminating the drive cylinder 80 and associated hoses and fluid conduits. In such case, an optional return spring may be installed to bias the ring gear 50 to its open position of FIG. 2. Such a spring can be a coil spring 150 shown in FIG. 5 connected between a convenient spacer sleeve 46 at 152 and an attachment point 154 on the outer circumference of the ring gear, to bias the ring gear for counter-clockwise rotation in FIG. 5.

As best appreciated in FIG. 1 the tong head housing is comprised of the two plates 42, 44 joined at the spacer sleeves 46, and is essentially open and largely unobstructed along all sides between the two housing plates. The open construction of the tong housing minimizes accumulation of dirt and debris in the tong mechanism, and permits easy inspection and cleaning of the same.

A further benefit of the open construction of the tong head housing is that removal and installation of the jaws 60, for example, for purposes of exchanging the jaw inserts 70, is greatly facilitated over previous Foster type tongs. Removal of the jaws 60 is easily accomplished as best understood by reference to FIG. 4. Each jaw 60 is held in place by the pivot pin 64 which is inserted through aligned pivot holes in the top and bottom plates 44, 42 and through the body of the jaw 60. The pivot 64 is held in place by a retaining clip 65 inserted transversely through the protruding lower end of the pivot exteriorly to the bottom plate 42. Removal of the jaw 60 merely involves extraction of the retaining pin 65 followed by removal of the pivot 64. This frees the jaw 60 from the top and bottom plates. The jaw can then be extracted from between the housing plates through the radial slot 56. The same procedure applies to each of the three jaws 60. Installation of the jaws is equally expedient. This procedure is facilitated by an indexing hole 160 provided in each jaw 60. The holes 160 align, in the open position of the jaws, with similar indexing holes in the top and bottom plates 42, 44. The indexing holes 160a in the bottom plate 42 are partially visible in FIGS. 3 and 5, and similarly positioned indexing holes 160b (only one of which is so designated in FIG. 1) are provided in the top plate 44. Each jaw is inserted between the top and bottom plates 42, 44 through the slot 56, and the jaw is positioned so as to align the indexing hole 160 with the corresponding alignment holes in the top and bottom housing plates. An indexing pin 67, seen in FIG. 1 inserted for storage in a convenient hole in the housing plates, is inserted into the indexing hole in the top plate 44. The jaw 60 is positioned until the pin 67 finds and passes through the indexing hole 160 in the jaw, after which the pin should pass without further difficulty into the corresponding indexing hole in the bottom plate 42. The indexing hole 160 is so located as to automatically position the toothed end 66 of the jaw for correct engagement with the ring gear 50 once the hole 160 is aligned with the indexing holed in the plates 42, 44. Installation of the jaw 60 is then completed by inserting the pivot pin 64 and retaining clip 65. The same installation procedure applies to each of the three jaws 60. The improved access to, and simplified removal and installation of the jaws minimizes the time and effort required to exchange the jaw inserts 70 for adapting the back up tong for larger or smaller diameter tubing. As best seen in FIG. 4, the insert 70 has a rear flange 73 which fits into a corresponding slot in the body of the jaw 60. Three bolts 74 pass through aligned holes in the jaw body and the flange 73, each bolt being retained by a nut 71. Exchanging the inserts after removal of the jaws from the tong 40 is quickly accomplished by removing the three bolts 74, exchanging the insert 70 and replacing the three bolts with their corresponding nuts 71.

I am chairman of the board, president and chief executive officer of Eckel International, the largest global providers of innovative and high performance hydraulic power tongs for the oil and gas industry. I am a second-generation family member involved in manufacturing of tongs. In 1993, as Eckel’s president, I launched an initiative to further reach out to Russia’s oil & gas needs. Today, I am directly responsible for the overall operations of the company, sales, and new market initiatives.

Since 1958 Eckel has been supplying power tongs to the worlds O&G industries– but how long have you been doing business in Russia and what specific solutions do you offer to the region?

Eckel specializes in the development of hydraulic power tongs for make-up and break-out of tubulars, with over 60 years of tubular connection experience. Our industry leading technology advancements are in some respects, a reflection on the industry requirements and their needs. Eckel has been in the process of designing tongs that required very high torques, advanced safety features, and automation.

Eckel in-house heating provides quality tempered steel while observing strict industry standards. This process assures high quality and rugged durable parts within Eckel power tongs. Eckel has won a world-wide reputation of providing first-class products that deliver years of trouble free service. Our tongs have operated trouble free in the harsh cold conditions of Western and Eastern Siberia and in the Far Northern Regions. Eckel’s hydraulic power units have a proven track record in some of the harshest surroundings in Russia such as the extreme hot and cold conditions of Russian and offshore environments.

Eckel has provided more than 500 Hydraulic Power Tongs to oil and gas companies and drilling contractors in Russia. In Russia, as well as in many other countries, the use of Corrosion Resistant Alloys (CRA) chrome tubulars are becoming more popular. Eckel is an industry leader in this specialized field tubular connections offering a line CHROMEBOSS® tongs along with Eckel Non-Marking True Grit® dies. True Grit® Dies utilize Tungsten Carbide grit coating which provides many more points of contact on the surface of the tubular than standard Pyramid Fine Tooth dies provide. Penetration depth less than half the depth that