Elevator for Tubular Handling

This application claims the benefit of the filing date of U.S. provisional application No. 63/644,912 filed on 9 May 2024. The entire disclosure of the prior application is incorporated herein by this reference for all purposes.

This disclosure relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in at least one example described below, more particularly provides an elevator for tubular handling, and associated systems and methods.

An elevator is used to suspend a tubular (such as, the types known to those skilled in the art as liner, casing, riser, tubing, pipe, screens, etc.) at a well rig. One type of elevator includes a slip assembly to grip an outside surface of the tubular, similar to a slip assembly of the type used in a spider typically secured in or on a rig floor.

It will, therefore, be readily appreciated that improvements are continually needed in the art of designing, constructing and utilizing elevators with subterranean wells. The present disclosure provides such improvements, which may be used with a wide variety of different types of well rigs.

Representatively illustrated inis a systemfor use in well operations, and an associated method, which can embody principles of this disclosure. However, it should be clearly understood that the systemand method are merely one example of an application of the principles of this disclosure in practice, and a wide variety of other examples are possible. Therefore, the scope of this disclosure is not limited at all to the details of the systemand method described herein and/or depicted in the drawings.

In theexample, a well rigis used to convey tubularsinto and out of a well. As depicted in, the well rigis a land-based rig, but in other examples the rig may be water-based. The tubularmay comprise equipment known to those skilled in the art as casing, liner, riser, tubing, pipe and similar tubular goods, including associated couplings, collars, etc.

To enable the tubularsto be supported by the rig, a lifting apparatusis provided with the rig. The lifting apparatusmay comprise, for example, a top drive or a draw works.

Bailsare connected at their upper ends to the lifting apparatus. At their lower ends, the bailsare connected to an elevator. The elevatoris specially configured to grip or otherwise support the tubular, so that a weight of the tubular (and any equipment, including additional tubulars, connected below the upper tubular) is supported by the elevator and the connected bailsand lifting apparatus. The elevator, with the bailsand lifting apparatuscan be used to raise or lower the tubularthrough a floorof the rig.

At different points in well operations, very different loads may be supported by the lifting apparatus, bailsand elevator. In addition, loads (such as, a weight of a tubular string suspended in the well) can be supported by a spidersecured in or on the rig floor.

When a load is being supported by the elevator, it is advantageous for the elevator to continue to support the load, until the load is supported by other equipment (such as, the spider). For example, if the elevatorreleases the tubularbefore it is supported by other equipment, the tubular (and any tubular string connected there below) will drop into the well, and costly and time-consuming remedial operations will need to be performed. In thesystem, the elevatoris provided with a load indicator that helps to ensure that the elevator will not release the tubularuntil after the tubular is supported by other equipment.

Referring additionally now to, an example of the elevatoris representatively illustrated. Theelevator may be used with thesystemand method, or it may be used with other systems and methods. For convenience and clarity, theelevatoris described below as it may be used with thesystemand method.

In theexample, the elevatorincludes an elevator housingwith outwardly extending “ears”. The earsprovide for attachment of the bails(see) to the elevator, so that the lifting apparatuscan support and lift the elevator and any tubular or tubular string supported by the elevator.

As depicted in, the elevatoralso includes a slip assemblyreceived in the elevator housing. The slip assemblyincludes multiple circumferentially spaced apart slipsand actuators(not visible in, see) for displacing the slips between open and closed positions. In an open configuration of the slip assembly, the slipsare positioned so that they will not grip a tubular(see) disposed in the elevator. In a closed configuration, the slipsare positioned so that they can grip a tubulardisposed in the elevator.

Control lines,are connected to a control system(see) for application of hydraulic or pneumatic pressure to actuate the slip assembly. In this example, fluid pressure is applied by the control systemto the line(and the lineis vented) to actuate the slip assemblyto its closed configuration, and fluid pressure is applied by the control systemto the line(and the lineis vented) to actuate the slip assembly to its open configuration.

The slip assemblyis axially displaceable a limited distance relative to the elevator housing. An outer housingof the slip assemblyis slidingly received in a central cavity of the elevator housing. An upper radially enlarged flangeof the slip assemblylimits downward displacement of the slip assembly relative to the elevator housing.

A load indicatoris disposed axially between the flangeand an upper end of the elevator housing. It will be readily appreciated that, when a load (such as, due to the weight of one or more tubulars) is supported by the slip assembly, and the elevator housingis supported by the bails, the load indicatorwill be compressed between the flangeand the upper end of the elevator housing.

In other examples, the load indicatorcould be positioned between other features of the elevator. For example, the load indicatorcould be positioned within the elevator housingand could be supported by an internal shoulder in the elevator housing, or the load indicator could be in contact with a portion of the slip assemblyother than the flange. Thus, the scope of this disclosure is not limited to any particular position or configuration of the load indicatoror any other component of the elevator.

In theexample, the load indicatorsurrounds the outer housingbelow the flange. The load indicatorincludes an upper ringand a lower ringthat each encircle the outer housingof the slip assembly.

Referring additionally now to, an example of the load indicatoris representatively illustrated. In this view it may be seen that the upper ringhas an upper surfacethat contacts the flange, and the lower ringhas a lower surfacethat contacts the upper end of the elevator housing, when the load indicatoris incorporated into the elevator.

Theload indicatorincludes multiple circumferentially distributed springsthat bias the rings,away from each other. In this example, the springsare coiled springs, but other types of springs (such as, Belleville washers, leaf springs, elastomers, etc.) may be used in other examples.

Theload indicatoralso includes multiple circumferentially distributed fluid springsthat can be pressurized (e.g., hydraulically or pneumatically) to bias the rings,away from each other. In this example, the fluid springscomprise pistons and cylinders, but other types of fluid springs (such as, diaphragms, bellows, etc.) may be used in other examples.

Note that it is not necessary for the load indicatorto include multiple types of springs,, for there to be the same number of each type of spring, or for the springs to be in any particular position relative to the upper and lower rings,. The scope of this disclosure is not limited to any particular type, configuration, or position of any springs used in a load indicator.

The springs,in theexample allow the upper and lower rings,to be displaced away from each other when a load is removed from the elevator. For example, when the load (such as, the weight of one or more tubulars) is taken by another item of equipment (such as, the spider), and the elevatoris lowered by the lifting apparatusin thesystemand method, the springs,can displace the upper ringupward relative to the lower ring. In order to achieve this result, the biasing force exerted by the combined springs,is greater than a combined weight of the upper ringand the slip assembly.

The upward movement of the upper ringwhen the load is removed from the elevatorcan be used to provide an indication that the load is no longer supported by the slip assembly. Once this indication is provided, the slip assemblycan be actuated to its open configuration, without any danger of inadvertently dropping one or more tubulars.

To provide this indication of the movement of the upper ringrelative to the lower ring, the load indicatorincludes a position indicator. In this example, the position indicatorcomprises a valve(see), but in other examples an electrical switch, position sensor, proximity sensor, Hall effect device, or other type of position indicator may be used.

Referring additionally now to, a partially cross-sectional view of the load indicatoris representatively illustrated. In this view it may be seen that the fluid springincludes a pistonslidingly and sealingly received in a cylinder. A seal between the pistonand cylinderis not depicted in, but a suitable seal (such as, an o-ring, v-packing, etc.) may be used as desired.

In theexample, the cylinderis formed as part of the upper ring, and the pistonis formed as part of the lower ring. In other examples, these positions could be reversed, or the pistonand cylindercould be separate from the upper and lower rings,.

As depicted in, a fluid passageis formed through the lower ringand the pistonto communicate with a chamberbetween the piston and the cylinder. In other examples, the fluid passagecould be formed through the upper ring, or the fluid passage may not be formed through either of the rings,(such as, if the pistonand cylinderare separate from the rings).

A lineis connected to the fluid passage. The linecan be used to communicate fluid pressure to the chamber, for example, to regulate a force output of the fluid spring. An increase of fluid pressure in the chamberwill cause an increase in the force output of the fluid spring, and a decrease of fluid pressure in the chamber will cause a decrease in the force output of the fluid spring. Thus, the force biasing the rings,away from each other can be adjusted to, for example, correspond to different loads being supported by the elevator.

Referring additionally now to, a portion of the load indicatorincluding the position indicatoris representatively illustrated. In this view it may be seen that the position indicatoris received in a recessformed in the lower ring. In other examples, the position indicatorcould be received in the upper ringor could be positioned in another portion of the load indicator.

In theexample, the position indicatoris positioned proximate one of the fluid springs. The position indicatorincludes a roller plungerthat can contact an extension or profiled camextending downwardly from the cylinderof the adjacent fluid spring.

In other examples, the cammay not be formed on the cylinderor another component of the fluid spring. Devices other than cams (such as, magnets, or structures capable of being sensed by a proximity sensor, etc.) may be used. As another example, the position sensorcould be rotated ninety degrees clockwise from itsposition, so that the plunger directly contacts the upper ring. Thus, the scope of this disclosure is not limited to any particular configuration, position or type of position indicator used with the load indicator.

In theexample, the plungeris depressed into a body of the position indicatorby the camwhen the upper ringis displaced upward relative to the lower ring. This depressing of the plungerwill cause the position indicatorto be actuated to a configuration in which opening of the slip assemblyis permitted.

When the plungeris not depressed by the cam(e.g., the plunger extends from the body of the position indicatoras depicted in), opening of the slip assemblyis prevented. In this example, the position indicatorincludes ports,for connection of the position indicatorin a fluid circuit(see) configured to prevent opening of the slip assemblywhen the position indicatorindicates that the upper ringis in its downwardly displaced position (as depicted in), and to permit opening of the slip assembly when the position indicator indicates that the upper ring is in its upwardly displaced position (so that the plungeris depressed by the camin theexample).

Referring additionally now to, a schematic view of one example of the fluid circuitis representatively illustrated. As depicted in, the slip assemblyis in its open configuration.

Pressure applied from the control systemto a lineis communicated via the position indicatorand a check valveto the open control lineconnected to the slip actuators(only one of which is shown in). The close control lineis vented back to the control system. The plungerof the position indicatoris depressed in this open configuration of the slip assembly.

In this example, the position indicatorcomprises a shuttle valve. In other examples, the position indicatorcould comprise another type of switch, proximity sensor, etc.

If power is lost, or the control systemcannot otherwise maintain the pressure on the open line, the check valve, a pilot operated pressure holding valveand a pilot operated shuttle valvewill prevent loss of pressure from the open control line, thereby maintaining the slip assemblyin the open configuration.

When it is desired to shift the slip assemblyto its closed configuration (e.g., so that the slipsgrip an outer surface of a tubularpositioned in the elevator), the control systemvents pressure from the open lineand applies pressure to the close control line. This causes the actuatorsto displace the slipsto their closed positions, in which they grip the outer surface of the tubular.

The pressure in the close control linecauses the shuttle valveto shift to a position in which the open control lineis vented back to the control systemvia the open line. The pressure in the close control linealso causes the pressure holding valveto shift to a position in which a linebetween the actuator, the open control lineand the pressure holding valveis vented.

Note that at this point the load indicatoris not in thefully compressed configuration, since the elevatoris not supporting at least the predetermined load. The springsare biasing the upper and lower rings,away from each other. The camin this example has depressed the plungerof the position indicator.

When the elevatoris raised by the lifting apparatus, the load indicatorwill be compressed by the load due to the weight of the tubulargripped by the slip assembly. This will cause the camto displace downward relative to the lower ring, thereby allowing the plungerto extend and shift the position indicatorto a position in which the open control lineis isolated. In this position, pressure applied to the open lineby the control systemwill not cause the slip assemblyto be actuated to its open configuration.

The elevatorcan be opened again only after the load is no longer supported by the elevator, such as, when the load is supported by the spideror another item of equipment. When the load is removed from the elevator, the load indicatorwill expand axially (an axial spacing between the upper and lower rings,will increase), due to the biasing force exerted by the springs, and the plungerof the position indicatorwill be depressed by the cam. This will allow the pressure applied to the open lineby the control systemto be communicated to the open lineand the actuator, and the close linewill be vented back to the control system, thereby shifting the slip assemblyto its open configuration.

Note that, in theexample, the fluid springsare not used. However, the fluid springscould be used with thefluid circuit, if desired.

Referring additionally now to, a schematic view of another example of the fluid circuitis representatively illustrated. As depicted in, the slip assemblyis in its open configuration. Operation of the slip assemblyusing the control systemis essentially the same in theexample as described above for thefluid circuit.

In theexample, the fluid springs(only one of which is depicted in) are used, and operation of the fluid springs is controlled by application of pressure to the open lineby the control system. A pressure relief valveand a check valveare connected in parallel between the fluid springsand the open line. When pressure is applied by the control systemto the open line, the check valvewill allow this pressure to be applied to the fluid springs, thereby applying a biasing force to urge the upper and lower rings,away from each other.

When the control systemapplies pressure to the close control line, the open control lineis vented, the slip assemblyis shifted to its closed configuration, at least a predetermined load is supported by the elevator, and the pressure relief valveallows fluid to vent from the fluid springto the open line(although some pressure can be retained in the fluid springs, depending on an adjustment of the pressure relief valve). This allows the load indicatorto be compressed by the load, so that the plungerof the load indicatoris extended (see), and the open control lineis isolated from the open lineas described above.

It may now be fully appreciated that the above disclosure provides significant advancements to the art of designing, constructing and utilizing elevators with subterranean wells. In examples described above, the elevatorcannot be inadvertently opened while at least a predetermined load is being supported by the elevator. Actuatorsof the slip assemblyare isolated from the open lineconnected to the control systemwhen the load is sufficient to compress the load indicator.

The above disclosure provides to the art an elevatorfor use with a subterranean well. In one example, the elevatorcan comprise: an elevator housing, a slip assemblyaxially displaceable relative to the elevator housing, the slip assemblycomprising multiple slipsconfigured to grip an outer surface of a tubulardisposed in the slip assembly, the slip assemblyhaving open and closed configurations, and a load indicatorconfigured to prevent actuation of the slip assemblyfrom the closed configuration to the open configuration when at least a predetermined load is supported by the elevator housing.

The slip assemblymay comprise an outer housinghaving a radially enlarged flange. The load indicatormay be positioned axially between the flangeand the elevator housing.