Overhead crane with remotely located winch

An overhead crane supported by a derrick, comprising a frame coupled to the derrick and comprising a pair of rail members and a bridge member coupled between the rail members, and a trolley coupled to the frame and comprising a fairlead assembly and a cable guide movable in an X-Y plane within an inner perimeter of the frame.

BACKGROUND

Field

Embodiments of the disclosure relate to a trolley for use on or as an overhead crane, such as a bridge crane, a cantilevered crane, or other overhead crane utilized to lift, lower, and move objects.

Description of the Related Art

Overhead cranes are utilized extensively in many industries to move objects. A bridge crane, sometime referred to as an offline activity crane (OAC), is one type of overhead crane that is utilized in the oil and gas industry. The bridge crane (or OAC) is mounted on an oil and gas rig above a fingerboard area for overhead lifting of tubulars.

Conventional bridge cranes typically include a bridge that travels along two parallel rails. The bridge supports a trolley that travels along the bridge in a direction normal to the rails. The trolley supports a winch that has a motor and drum, which contains wire rope used to raise and lower a lifting hook coupled to the end of the wire rope. The winch is heavy and adds a significant amount of load that the trolley and ultimately the bridge crane must support, which reduces the overall lifting capacity of the bridge crane.

Therefore, there exists a need for new and improved overhead cranes.

SUMMARY

Embodiments of the disclosure relate to an overhead crane comprising a trolley that moves within an X-Y plane relative to a support structure.

In one embodiment, an overhead crane supported by a derrick is provided that includes a frame coupled to the derrick and comprising a pair of rail members and a bridge member coupled between the rail members, and a trolley coupled to the frame and comprising a fairlead assembly and a cable guide movable in an X-Y plane within an inner perimeter of the frame.

In another embodiment, overhead crane supported by a derrick is provided that includes a frame coupled to the derrick and comprising a pair of rail members and a bridge member coupled between the rail members, wherein the bridge member is movable relative to the rail members, a trolley coupled to the frame and comprising a fairlead assembly and a cable guide movable in an X-Y plane within an inner perimeter of the frame, wherein the cable guide is movable relative to the bridge member, and wherein the fairlead assembly comprises one or more arms coupled to one or more sheaves, and a winch coupled to the derrick at a location remote from the trolley, wherein the winch has a cable that is routed along the one or more sheaves of the fairlead assembly from which a hook is suspended.

In another embodiment, overhead crane supported by a derrick is provided that includes a frame coupled to the derrick and comprising a pair of rail members and a bridge member coupled between the rail members, and a trolley coupled to the frame and comprising a fairlead assembly and a cable guide coupled to the bridge member, wherein the cable guide is movable in an X-Y plane within an inner perimeter of the frame, wherein the fairlead assembly comprises a pair of arms, a central pivot point located between the arms, and peripheral pivot points located at opposite ends of the arms, wherein a distance between the central pivot point and each of the peripheral pivot points is equal.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized with other embodiments without specific recitation.

DETAILED DESCRIPTION

Embodiments of the disclosure relate to an overhead crane comprising a trolley that moves within an X-Y plane relative to a support structure. The trolley is coupled to a remotely located winch in order to reduce the overall weight of the overhead crane. The overhead crane may be utilized to replace any conventional bridge crane, such as an offline activity crane (OAC) utilized for handling tubulars on a land based or offshore oil and gas rig according to one embodiment. The overhead crane disclosed herein may also be utilized to replace other types of cranes that are supported by a support structure.

FIG. 1is a side view of an overhead crane100according to one embodiment described herein. The overhead crane100is supported by a support structure105which, in this embodiment, is a derrick110. The overhead crane100includes a frame115, a trolley130, and a winch142. The frame115, which is coupled to the derrick110, includes a pair of rail members120(only one is shown inFIG. 1) that extend in the X direction, and a bridge member125that extends in the Y direction between the rail members120. The rail members120and the bridge member125support the trolley130.

The trolley130is coupled to the frame115and comprises a fairlead assembly135and a cable guide150. The fairlead assembly135is coupled to the cable guide150at one end and follows the cable guide150as it moves along the bridge member125and as the bridge member125moves along the rail members120. The fairlead assembly135includes a pair of arms148coupled to four sheaves145. Although two arms148and four sheaves145are shown, the fairlead assembly135may include any number of arms (e.g. one or more arms) coupled to any number of sheaves (e.g. one or more sheaves). A cable140, such as a wire rope, extending from the winch142to a hook144is routed around the sheaves145that are coupled between or to one or more of the arms148. The winch142may be coupled to the derrick110at a location remote from the trolley130, such as by being mounted on the floor of the derrick110. As illustrated, the winch142comprises a rotatable drum about which the cable140is spooled. The winch142however may comprise other types of hoisting devices. The cable guide150is movably coupled to the bridge member125and guides the cable140along the fairlead assembly135as it is payed-out and taken-in by operation of the winch142. According to one example, a single joint elevator may be suspended from the hook144to move one or more tubulars on the derrick110.

The cable guide150, is capable of being moved in the X direction and the Y direction (e.g., within the X-Y plane) based on articulation of the arms148of the fairlead assembly135. A surface area155that is serviced by the overhead crane100is defined by the dimensions of the rail members120and the bridge member125. For example, a length of the rail members120defines movement of the cable guide150in the X direction, and the spacing between the rail members120(spanned by the bridge member125) defines movement of the cable guide150in the Y direction. The overhead crane100may service a surface area155of about 16 feet by about 20 feet in one embodiment, or a surface area155of about 36 feet by about 36 feet in another embodiment. The dimensions of the overhead crane100may be configured to service a surface area of any size.

FIG. 2is a top view of the overhead crane100. The trolley130is shown coupled to the frame115. The frame115further includes a supporting structure shown as a first support structure200and a second support structure205opposing the first support structure200. In the embodiment shown inFIG. 2, the first support structure200includes an extended central support member210coupled to peripheral support members215by support plates217. Each of the peripheral support members215are coupled to one end of each of the rail members120. The second support structure205includes a single support member220that is coupled to opposing ends of the rail members120. Each of the support members210,215, and220may include but are not limited to metallic structural members, such as angle iron, tubing, channel iron, I-beams, W-beams, and/or other structural shapes. Similarly, each of the rail members120and/or the bridge member125may include but are not limited to metallic structural members such as angle iron, tubing, channel iron, I-beams, W-beams, and/or other structural shapes.

One end of the fairlead assembly135is coupled to the central support member210of the first support structure200by a swivel device225. The swivel device225may be a passive bearing device that allows movement of the one end of the fairlead assembly135in the direction indicated by arrow230. The swivel device225may be a slewing bearing or other type of bearing.

The bridge member125is movable along the rail members120by one or more motors235coupled between the bridge member125and the rail members120. The cable guide150is movable along the bridge member125by one or more motors236coupled between the cable guide150and the bridge member125. Actuation of the motors235,236allows the cable guide150to be positioned within an inner perimeter240defined by the rail members120and the first and second support structures200,205. Additionally, the cable guide150is movable relative to the bridge member125within the inner perimeter240. The inner perimeter240substantially corresponds to the surface area155shown inFIG. 1.

Although multiple motors235,236are shown inFIG. 2, at least one motor may be used to move both the bridge member125along the rail members120, as well as move the cable guide150along the bridge member125. The motors235,236may be electrical, electromechanical, hydraulic, and/or other types of motors or actuators. The motors235are lighter in weight than any motors mounted on conventional bridge cranes. Additionally, numerous other components of the winch mounted on conventional bridge cranes are effectively eliminated or reduced, which decreases the dead weight of the overhead crane100as described herein when compared to conventional bridge cranes.

FIGS. 3A and 3Bare various side views of the overhead crane100.FIG. 3Ais a side view of the overhead crane100along lines3A-3A ofFIG. 2.FIG. 3Bis a side view of the overhead crane100along lines3B-3B ofFIG. 2.

The trolley130is configured so that a hook height300as shown inFIG. 3Aremains constant as the cable guide150is moved along the bridge member125and as the bridge member125is moved along the rail members120. The hook height300is defined from the cable guide150to the hook144coupled to the cable140. The hook height300remains constant so long as the winch142is not paying-out or taking-up the cable140. Thus, when the winch142is not paying-out or taking-up cable140, the hook height300stays the same during articulation of the trolley130in at least the positions shown inFIG. 3A(as well as other positions within the range of articulation of the trolley130). To ensure that the hook height300remains constant, distances D1and D2between a central pivot point305(located between the arms148) and peripheral pivot points310(located at the opposite ends of the arms148) of the fairlead assembly135are equal. The lengths of the arms148of the fairlead assembly135may be the same. A wrap angle is located about each of the peripheral pivot points310and the central pivot point305. As shown inFIG. 3A, wrap angles A1, A2, and A3when added together equal the sum of 180 degrees regardless of the position of the fairlead assembly135.

FIGS. 4A, 4B, and 4Care various isometric top views of the overhead crane100showing the range of movement of the trolley130. The range of movement of the trolley130provides precise positioning of the cable guide150and the hook144.FIG. 4Ashows the trolley130in a central position within the inner perimeter240.FIG. 4Bshows the trolley130in one fully extended position at one corner of the inner perimeter240.FIG. 4Cshows the trolley130in another fully extended position at the opposite corner of the inner perimeter240. The trolley130is moveable to any location within the inner perimeter240to thereby move the hook144(shown inFIG. 3A) and anything being supported by the hook144as needed.

While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure thus may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.