Compact articulation mechanism

An articulation mechanism for large scale mobile aggregate system equipment. The mechanism includes a screw device that is pivotally secured to an elongated portion of the equipment to drive its movement to and from a collapsed position. The screw device is driven by a screw jack and moved within a housing while the housing itself is pivotally secured to another portion of the equipment. Rollers within the housing may be used to stabilize the lateral movement of the screw device during the opening, closing or self-locking of the elongated portion by the mechanism.

BACKGROUND

Exploring, drilling and completing hydrocarbon and other wells are generally complicated, time consuming and ultimately very expensive endeavors. As a result, over the years, well architecture has become more sophisticated where appropriate in order to help enhance access to underground hydrocarbon reserves. For example, as opposed to wells of limited depth, it is not uncommon to find hydrocarbon wells exceeding 30,000 feet in depth. Furthermore, today's hydrocarbon wells often include deviated or horizontal sections aimed at targeting particular underground reserves. Indeed, at targeted formation locations, it is quite common for a host of lateral legs and fractures to stem from the main wellbore of the well toward a hydrocarbon reservoir in the formation.

The above described fractures may be formed by a fracturing operation, often referred to as a stimulation operation. The stimulation or fracturing operation, involves pumping of a fracturing fluid at high pressure into the well in order to form the fractures and stimulate production of the hydrocarbons. The fractures may then serve as channels through the formation through which hydrocarbons may reach the wellbore. The indicated fracturing fluid generally includes a solid particulate referred to as proppant, such as sand. The proppant may act to enhance the formation of fractures during the fracturing operation and may also remain primarily within fractures upon their formation. In fact, the fractures may remain open in part due to their propping open by the proppant.

The above described proppant for the fracturing operation may be supplied from a proppant delivery unit located at the oilfield near the well. This unit is generally very large due to the amount of proppant that may be required for any given fracturing operation. For example, where the proppant is a conventional dry sand, a fully loaded unit may exceed half a million pounds in weight. Once more, as wells become deeper and of ever increasing complex architecture, efforts to provide even larger ready supplies of proppant at the oilfield are increasingly common. That is, more downhole fracturing locations may be involved, thus requiring a greater available supply of proppant.

From an equipment standpoint, greater on-site or near-site supplies of proppant may include the use of mobile silos or even larger stationary silos that are used to gravity feed a blender therebelow. Thus, a proppant slurry may be formed and utilized in short order to support various fracturing operations. As a practical manner, however, this means that potentially several million pounds of proppant may require transport and storage at a given location. Adding to this is the weight and footprint issues for the equipment itself which is necessary to allow for such a ready bulk supply.

In terms of limiting the overall footprint, a variety of systems may be available. For example, systems may be utilized in which smaller silo-like storage containers are transported to the oilfield and then erected to a vertical position. Thus, the footprint of the equipment may be reduced due to the vertical orientation and follow-on gravity feeding, mixing and use of a frac slurry may ensue.

Unfortunately, while this does address footspace issues to a degree, erecting a proppant loaded silo has its practical limitations. For example, erecting more than a few million pounds of a proppant filled silo may be impractical with conventionally available hydraulics. Thus, on larger job sites with more fracturing operations, the need to deliver several such small loaded silos may exist.

As an alternative to delivering small loaded silos, efforts have been undertaken to install larger, more permanent silos that may be empty when installed but subsequently filled with proppant for use at the oilfield. Again, the vertical orientation of such on-site silos helps keep footspace devoted to fracturing equipment to a minimum. Once more, such larger silos may be gravity fed and outfitted with mixing equipment and other features therebelow for ongoing operational use. However, setting up and filling these larger silos with proppant may come with challenges as well.

For example, in order to maximize efficiencies in terms of set up time and filling, unique modular forms of equipment may be employed. More specifically, a mobile compacted silo base frame may be positioned at the oilfield with a truck, unfolded and utilized as the foundation for the erection of a multi-unit silo thereover. Similarly, mobile compacted elevators with extendable auger arms may be positioned at the oilfield with another truck, vertically erected, and later utilized to transfer proppant from delivery trucks to the silo. In this way, a much greater amount of proppant may be made available at the oilfield site in a space saving fashion.

The process of unfolding the silo base frame or extending the auger arms face the unique challenge of re-orienting or articulating several thousand pounds of tension within a compact limited space of operation. That is, unlike erecting an elevator to a vertical position, the space for accommodating large scale hydraulics is unavailable for wings of the silo base frame and/or the auger arms.

SUMMARY

An articulation mechanism is provided as a support to a hinge at an interface between elongated portions of oilfield aggregate delivery equipment. The mechanism includes a screw device that has one end pivotally secured to a first of the elongated portions but insecure at an opposite end thereof. A housing is additionally provided about the screw device and is located between the device ends for stably accommodating the device therethrough. Thus, it is the housing that is secured to a second of the elongated portions. Further, a screw jack may be coupled to the housing between the ends of the device for sake of lateral and substantially locking engagement therewith.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to provide an understanding of the present disclosure. However, it will be understood by those skilled in the art that the embodiments described may be practiced without these particular details. Further, numerous variations or modifications may be employed which remain contemplated by the embodiments as specifically described.

Embodiments are described with reference to certain embodiments of compact articulation mechanisms utilized in aggregate management equipment. Specifically, equipment for the transport, delivery and storage of oilfield proppant is discussed which utilizes such articulation mechanisms to support joints at large base frame units which in turn support large scale silos as well as at auger units to support the extension of auger arms for proppant delivery. However, other uses for such compact articulation mechanisms may be employed. For example, outrigger support frames, ramps, fracturing blender assemblies and other heavy jointed oilfield equipment may incorporate embodiments of such articulation mechanisms. Indeed, so long as the mechanism incorporates a screw jack and screw device that substantially locks and in which one end of the device is pivotally secured to one of the elongated portions defining the joint but the other end is left insecure, appreciable benefit may be realized. That is, a unique compactness may be provided with such configurations where the other of the elongated portions defining the joint is instead pivotally secured to a housing about the device as detailed herebelow.

Referring now toFIGS. 1A and 1B, a side partially-sectional view of an embodiment of a compact articulation mechanism100is shown. The articulation mechanism100may be utilized to support a joint between adjacent elongated portions of large scale oilfield equipment. For example, a joint may be found between a frame210,335and extendable or collapsable wings330or auger arms275relative thereto (seeFIGS. 3A and 4A). Such an articulation mechanism100may be utilized to stably support the sizable weight of such features during extending or collapsing thereof. Once more, the mechanism100may provide secure immobilization or locking in place of such features even in absence of any ongoing extending or collapsing.

As shown inFIG. 1A, the mechanism100includes a screw device110that is shown in a retracted lateral position. More specifically, with respect to a surrounding extension housing150of the mechanism100, the device110is shown substantially retracted thereinto. To the contrary, in the depiction ofFIG. 1B, the screw device is shown noticeably extended laterally out of the housing150.

As the screw device110moves laterally to varying degrees, from one position to another, the housing150utilizes rollers140to enhance stability of the device110. Enhancing stability may be of substantial benefit where a significant load is secured to the exposed end175of the screw device110. For example, in the embodiment shown, the exposed end175includes a clevis connection185for pivotally securing to a heavy articulated or elongated portion of equipment as alluded to above. Thus, during lateral movement of the screw device110, a degree of stabilization is provided at one location by the noted rollers140. The added stability here may substantially eliminate any bending load on the screw device110from the secured articulated portion of equipment as detailed below.

In addition to the stabilization provided by the rollers140, the screw device110is laterally moved backward or forward into or out of the housing150by a screw jack120. Thus, the engagement of a threaded region112of the screw device110with the screw jack120provides another location of stabilization for the device110. That is, unlike the exposed end175, the opposite end of the screw device110remains insecure relative another elongated portion of equipment such as a frame210,335, wing330, or auger arm275(seeFIGS. 3A and 4A). Instead, this other equipment portion may be pivotally secured to the housing150as detailed further below. Regardless, additional stability is provided to the screw device110through the engagement of the threaded region112with the screw jack120. In the embodiment shown, the screw jack120may be of an about twenty ton to about forty ton variety, although screw jacks of other ratings may also be employed.

In the embodiment shown, the insecure end of the device110which may include the threaded region112may recede into a cylindrical protective covering125. This covering125may serve to keep the surface of the threaded region112shielded from debris. However, in this embodiment, the covering125may not be relied upon for any substantial supportive functionality.

Utilizing a screw jack120to linearly or laterally move the screw device120between a retracted position as shown inFIG. 1Aand an extended position as shown inFIG. 1Bprovides certain additional advantages. For example, unlike extending a conventional hydraulic arm, the need for a constant supply of power may be avoided due to the self-locking nature of the mechanism as detailed further below. Once more, the space requirements for a screw jack120are comparatively compact. That is, a large range of motion is available from the mechanism100via the screw jack120. This is illustrated in the comparison of the different positions of the screw device110when moving from the retracted positon ofFIG. 1Ato the extended position ofFIG. 1B. It is clear that nearly the entirety of the threaded region112advances through the screw jack120for the sake of a stroke that extends the device110.

The self-locking nature of the screw jack120may be inherent in such device types depending on the gear ratio involved. For example, as indicated above, the threaded region112of the screw device110engages the jack120which is used to rotatably extend or retract the device110in a lateral fashion. More specifically, the jack120includes a bearing mounted rotatable nut (not shown) or other matching threaded feature about the threaded region112. This feature is rotatably driven by a hydraulic or other conventional compact motor130to laterally extend or retract the screw device110depending on the direction of rotation of the feature. Thus, as is the case with such gear-driven mechanisms, a variety of gear ratio options may be available in driving such a rotation. For example, the gear ratio may be 2 to 1, 50 to 1, or any number of ratios in between or even outside of such ranges.

For embodiments detailed herein, the jack120is utilized to stably support opening, closing or otherwise supporting elongated equipment portions of potentially several thousand pounds in an environment involving a fair amount of vibration. Thus, it is advantageous to utilize a screw jack120which is likely to demonstrate a substantially “self-locking” nature. By way of specific example, in such an environment, a 30 ton jack120with a gear ratio of 32 to 1 would be substantially self-locking. That is, in spite of the weight and tension involved, and even the potential vibrating nature of the environment, the likelihood of the jack120being backdriven with the elongated equipment falling, lowering or becoming unsupported would be negligible.

Once more, this substantially self-locking nature of the articulation mechanism100does not require a constant power supply to achieve. Rather, the power supplied through the motor130may simply be turned off whenever the screw device110is in the appropriate lateral position and the joint will remain supported or “locked”. This is illustrated in the embodiments detailed below where heavy elongated wings330are locked in place by an articulation mechanism100for sake of transport or where elongated auger arms275are locked in position by another mechanism100for delivery of aggregate (seeFIGS. 4A and 4C).

In an embodiment, another stabilizing feature of the articulation mechanism100is found in the fact that the extension housing150may be substantially rectangular, for sake of accommodating rollers140at multiple flat surfaces thereof as shown. This rectangular shape of the housing150also receives a matching rectangular shape of the screw device110. That is, while the threaded region112of the screw device110is provided for engaging the screw jack120as described above, it does not rotate as this function is provided by the jack120itself as described above. Therefore, a rectangular region114of the device110may be provided for securably moving linearly within the rectangular housing150. Thus, as the device110moves from position to position, it does so stably with a reduced likelihood of rotation or other destabilizing motion.

Referring now toFIG. 2, a perspective overview of an aggregate silo system225is shown. The system225includes multiple hinge locations where the articulation mechanism100ofFIGS. 1A and 1Bmay be utilized. Specifically, with added reference toFIGS. 3C and 4C, a mobile base frame230and auger unit220are shown following tractor-type delivery with elongated equipment portions in the form of wings330and auger arms275are found. As alluded to above, using articulation mechanisms100as an aid to deploying these features may be of substantial benefit given their heavy articulated nature.

As a practical matter, safety concerns for operators at the worksite200are evident given the massive scale involved. For example, apart from the multiple ton mobile base frame230and auger unit220, a comparably massive mobile mixing equipment240is provided for docking to and/or supporting several ton capacity silo units250which accommodate aggregate such as proppant. Thus, as each of these pieces of equipment is installed as shown, safe and secure measures may be taken to ensure operator safety as well as long term stability of the system225. Along these lines, enhanced security is provided in large measure to the wings330and auger arms275via the articulation mechanisms100.

Continuing with reference toFIG. 2, the silo system225is set up by delivery of the base or mobile base frame230to the worksite200. Wings or extended bases330of the frame230are deployed to the position depicted with aid of an articulation mechanism100. As detailed further below, this articulation mechanism100is of particular benefit during transport of the frame230. Regardless, mobile mixing equipment240and auger unit220are positioned as shown. Specifically, the auger unit220is positioned in a collapsed form followed by extension of the auger arms275with aid of another articulation mechanism100and raising of an elevator210via hydraulic arms215. Thus, at some point, delivery trucks may be driven over folding ramps219to drop proppant or other aggregate onto a conveyor belt217which sends the proppant over to the elevator210and eventually to the auger arms275and chutes280for filling of the silo250. As a result, the in-place mixing equipment240may be used to provide a slurry of the proppant on an as needed and long term basis at the worksite200.

In the embodiment shown, the conveyor belt217is folded prior to use. However, it may be unfolded for use as described. Additionally, in an embodiment, the belt217may be more of a telescoping configuration.

Referring now toFIG. 3A, a rear view of a mobile base frame230is shown for the system225ofFIG. 2. In this depiction, multiple articulation mechanisms100are shown with their screw devices110in a retracted and locked lateral position. That is, recalling that the mechanisms100may be self-locking in nature, they may be used to lock the heavy wings330in place for transport. Further, keeping in mind that the mobile base frame230may be a truck/tractor driven assembly of extremely high weight; as a matter of safety, the mechanisms100are configured such that maximum stability is provided during transport. For example, the wings330which are folded up for transport may each weigh 15,000 to 25,000 lbs. or more. Thus, it is advantageous during transport that the mechanisms100secure the wings330upright for transport while having the screw devices110retracted and of most secure and stabilized positioning within the extension housing150(e.g. seeFIG. 1A). Indeed, even though the load of the wings330is likely to be minimal on the devices110during routine transport, the possibility of wind, accidents or other potential issues remain. Thus, maximum reliability and security of the mechanisms100in terms of retaining the wings330in a folded upright position as shown, is of particular benefit during transport.

Continuing now with added reference toFIG. 3B, a perspective view of one of the articulation mechanisms100ofFIG. 3Ais shown. Specifically, the mechanism100is shown with the screw device110shifted to an extended lateral position. In this depiction, the curved “boomerang” shape of supplemental links320,350is apparent. That is, as the screw110extends from the housing150as driven by the motor130and screw jack120, a joint360of these links320,350opens up allowing them to provide added support. Specifically, a secondary link320is pivotally secured to the clevis connection185(seeFIG. 1A) of the wing330whereas the primary link350is pivotally secured to the housing150. Thus, added stability is provided as the wing330is unfolded from the transport orientation shown ifFIG. 3Ato the deployed positioning shown inFIG. 3Cdiscussed below. It is of note that the primary link350is pivotally secured to the housing150at a substantially central location thereof. However, in other embodiments, such as the auger arms275discussed above and further below, the housing150may include pivotal connection at more of an offset location (e.g. see180ofFIG. 4A).

Continuing now with added reference toFIG. 3C, a rear view of the mobile base frame230ofFIG. 3Ais shown with the screw device110in its fully extended lateral position and secured to the wings330, now fully deployed. In this view, the full range of motion provided by the articulation mechanisms100is readily apparent. Additionally, it is worth noting that the maximum load placed on the articulation mechanisms100by the wings330, just prior to the wings330reaching the ground for support, may approach 35,000 lbs. or more. Yet, at this time, the frame230is in position for deployment as opposed to on the road for transport. Thus, from a safety standpoint, this is a uniquely opportune time for the mechanisms100to experience such a load, if needed.

Continuing now with reference toFIG. 4A, a side perspective view of a mobile auger unit220for the system ofFIG. 2is shown. Specifically, the articulation mechanism100is depicted with the screw device110thereof in an extended lateral position. That is, unlike the screw device110for the articulation mechanism100of the base frame230ofFIG. 3A, the device110for the auger unit220is extended during transport. This is because the heavy elongated auger arms275are already naturally horizontally secure during transport as shown, in contrast to the elongated wings330ofFIG. 3A. As a result, the more stable and secure positioning of the screw device110, retracted to within the housing150may instead be utilized where it is of greater advantage (e.g. when the arms275are locked open during use as shown inFIG. 4C).

Continuing with reference toFIG. 4A, as indicated above, the unit220is shown folded up for transport with the elevator210and arms275both horizontally secure to a mobile tractor bed. The screw jack120of the articulation mechanism100may be of a gear ratio to effectively lock the screw device110in position as shown. Specifically, the device110may hold the clevis connection185(seeFIG. 1A) of the arms275in place, preventing any extending movement of the arms275about an elevator pivot location450. Nevertheless, as alluded to above and detailed further below, once in position for deployment, hydraulic lines420may direct a hydraulic motor130at the screw jack120to retract the screw device110over the rollers140and into the housing150. In an embodiment, the screw jack120may be driven by an electric motor, a pneumatic motor, or manually driven with a crank (of appropriate size for the torque required to retract the screw drive110), as will be appreciated by those skilled in the art.

With added reference toFIG. 4B, retracting the screw device110into the housing150may take place until the arms275are raised and locked into the vertical position shown. Of course, in other embodiments, the nature of the articulation mechanism100is such that the arms275may be raised beyond vertical or 90° should this be desirable. Regardless, as the arms275raise, they are articulated about the noted elevator pivot location450and the threaded region112of the screw device110is pulled into the protective covering125as described above. At this time, the housing150may rotate to a degree about the offset clevis180as also described above. Perhaps most notably though, the articulation mechanism100achieves this motion while taking on a significant load. For example, each arm275may be 12 to 14 feet long and weigh several thousand pounds. Just as the arms275begin to raise, the load on the screw device110and mechanism100from the arms275may exceed 20,000 lbs., eventually settling down to a load of 5,000-10,000 lbs. once raised to a rested vertical position as shown. Nevertheless, the unique nature of the screw jack120is such that sufficient power for the maneuver may be readily obtained from a small scale, compact hydraulic motor130as shown.

Referring now toFIG. 4C, a side perspective view of the unit220ofFIG. 4Ais shown raised to a vertical position. That is, the elevator210of the unit220is fully raised up while the articulation mechanism100remains locked in place, allowing the auger arms275to take on a horizontal orientation.

With added reference toFIG. 2, raising of the elevator210in this manner may be achieved through conventional hydraulic arms215. Regardless, once in position, the auger arms275may be used to deliver aggregate such as proppant to the silos250of the system225. Thus, the load on the articulation mechanism100may be quite significant. For example, holding the arms275alone in this manner may place several thousand pounds of tension on the mechanism100. However, once filled with a proppant such as bauxite, the overall tension may exceed 45,000 lbs. and for an extended period of use (e.g. as the proppant is delivered to the system225). Thus, in this particular embodiment, it is advantageous to extend the arms275by retraction of the screw device110into the housing150where maximum stability is achieved for the mechanism100.

Referring now toFIG. 5, a flow-chart is shown summarizing an embodiment of employing an articulation mechanism at a joint between an elongated portion and other aggregate delivery equipment portions. Specifically, large-scale equipment may be delivered to a worksite in a collapsed fashion as indicated at510. In cases where it is most advantageous for the delivery to include use of an articulation mechanism with a retracted screw device, the device may then be extended as indicated at530(e.g. see the wings330ofFIG. 2). Alternatively, in situations where it is more advantageous for the screw device to be retracted during operation, the mechanism may be extended during delivery (see the arms275ofFIG. 2). Thus, upon delivery, the screw device may be retracted as indicated at550.

In response to appropriate extending or retracting of the screw device, the elongated portion of the equipment may be actuated into an operating position as indicated at570. For embodiments described herein, this may include mobilizing a support frame or achieving a horizontal position for auger arms as noted. Regardless, as indicated at590, this may be followed by an appropriate worksite application such as securing silos at a mobilized frame or delivering proppant thereto from auger arms.

Embodiments described above allow for a more practical utilization of on-site silos filled with proppant. That is, challenges associated with raising pre-filled silos may be avoided while also allowing for a larger scale silo system. Specifically, the modular nature of the larger scale system is supported by the use of compact articulation mechanisms that render the compact transport and subsequent deployment of sizable equipment more practical. In spite of the potentially tens of thousands of pounds involved, embodiments of articulation mechanisms detailed hereinabove allow for deployment of a modular base frame, auger arms and other equipment in a compact and practical manner.

The preceding description has been presented with reference to presently preferred embodiments. Persons skilled in the art and technology to which these embodiments pertain will appreciate that alterations and changes in the described structures and methods of operation may be practiced without meaningfully departing from the principle, and scope of these embodiments. For example, in the embodiments detailed above, a single articulation mechanism is depicted for a given base wing or even for a pair of auger arms. However, in other embodiments, the numbers may differ. For example, multiple articulation mechanisms may be used per base wing or each auger arm outfitted with its own dedicated mechanism. Furthermore, the foregoing description should not be read as pertaining only to the precise structures described and shown in the accompanying drawings, but rather should be read as consistent with and as support for the following claims, which are to have their fullest and fairest scope.