TECHNICAL FIELD

[0001] The present disclosure relates generally to a self-elevating work platform. Embodiments of the disclosure are related to a system and method of using redundant power of hydraulic power units of jack system for crane operations in Self- Elevating Work Platform (SEWOP).

BACKGROUND

[0002] The Self-Elevating Work Platform (SEWOP) is a self-propelled barge equipped with system for jacking the barge out of and in water as per the requirement. SEWOPs are extensively used in the oil and gas industry. Most of the SEWOPs have jacking system which are hydraulic actuated and thus have dedicated hydraulic power units. The SEWOP have a hull and one or more legs and are fitted a crane. The cranes are self-powered with diesel engine which powers the hydraulic power units. The SEWOP transports itself to a deployment site, where the legs are elevated above the hull and the hull is floated on its own buoyancy.

[0003] Also, known in art are leg Encircling Cranes (LEC) and pedestal cranes which run independent of the SEWOP main electric circuit. Majority of the SEWOP in the industry are fitted with hydraulic jacking system in which a jacking pinion is powered by a hydraulic motor which receives hydraulic power from an electric driven power unit. The cranes are self-powered by a dedicated diesel engine which powers the hydraulic unit to drive hydraulic motors of the cranes. [0004] According to SEWOP known in art, some have The LEC and pedestal cranes have main and auxiliary hoists, the boom stopper, machine house, mast, crane boom and wire rope which are utilized for lifting and material handling at site. A jack house is positioned on the main deck of the SEWOP is used for elevating the SEWOP. The hydraulic power unit of jacking system is utilized to jack the SEWOP above or below the sea level.

[0005] According to conventional SEWOP, diesel hydraulic pedestal cranes have machine house which includes hydraulic motors, hydraulic power unit and a diesel engine. The pedestal crane and LEC are self-powered by a dedicated diesel engine which powers the hydraulic power unit with a control valve bank to drive all the hydraulic motors of the pedestal crane or the LEC. The hydraulic motors can be hydraulic motors of a main hoist, an auxiliary hoist, a boom position hoist and slew ring. A Jack unit receives hydraulic power from dedicated electrically driven hydraulic power unit for lowering and raising the platform.

[0006] Also known in art are electric powered pedestal cranes powered by main electric power supply to run all its electric motors. The electric motors can be electric motors of a main hoist, boom raising or positioning hoist, an auxiliary hoist and slip ring.

[0007] According to few known configurations of prior art of SEWOP, a hydraulic pump receives hydraulic power from a diesel engine and through a control valve bank, the hydraulic power is supplied to the hydraulic motors of main hoist, auxiliary hoist, boom position and slew ring of the crane. The hydraulic pump receives hydraulic power from the electric motor to drive the hydraulic motors of main hoist, auxiliary hoist, boom position and slew ring drive of the crane.

[0008] According to few other configurations of SEWOP known in art a variable frequency drive bank supplies the electric power from main electric supply circuit to the electric motors of main hoist, auxiliary hoist, boom position hoist and slew ring drive of the crane respectively. Thus, all the motors of crane are operated by electric power.

[0009] It is apparent from the above description that the cranes of SEWOP known in art have dedicated power systems for example diesel engine or electric power systems which drives hydraulic or electric motors of the crane. Similarly SEWOP which have hydraulic jacking system having jacking pinion, are powered by a hydraulic motor driven by an electric power unit. Cranes and jacking system have individual and independent dedicated power systems for their operation.

[0010] Usage of diesel engine for powering hydraulic power units of cranes produces environmental pollution and high level of noise. Further, engine driven hydraulic power units for crane operation increases the spare parts inventory, capital and maintenance costs. Thus, there arises a need to develop an efficient SEWOP wherein the utilization of hydraulic power is optimized appropriately.

SUMMARY

[0011] The following summary is provided to facilitate an understanding of some of the innovative features unique to the disclosed embodiment and is not intended to be a full description. A full appreciation of the various aspects of the embodiments disclosed herein can be gained by taking into consideration the entire specification, claims, drawings, and abstract as a whole.

[0012] It is, therefore, one objective of the disclosed embodiments to provide for a self-elevating work platform, comprising a hull; at least one leg attached to the hull; at least one jacking system having at least one hydraulic power unit with a manifold; at least one crane, comprising a crane hydraulic system, connected to the hydraulic power unit of the jacking system, through a hose, a valve block on a machine house of the crane; and wherein the manifold on the hydraulic power unit diverts high pressure hydraulic oil from hydraulic power unit of the jacking system to the valve block on the machine house of the crane hydraulic system of the crane through the hose.

[0013] The diverted power of the jacking system enables the cranes for lifting the materials on the elevated platform and lowers it at a desired location. Through this embodiment it is possible to initially use the hydraulic power units of the jacking system to elevate the platform and then use the hydraulic power units for lifting the materials from the elevated platform.

[0014] It is therefore, another objective of the disclosed embodiments to provide the SEWOP wherein the crane is pedestal lifting and lowering device and the hose is a rotary hose.

[0015] It is therefore, another objective of the disclosed embodiments, in the Leg Encircling crane, the hose is around a hose reel mounted on top of a jack house.

[00 6] It is therefore, another objective of the disclosed embodiments to provide the SEWOP wherein a hose tray is mounted on top of the jack house, for laying the hose on itself without entangling when the machine house of the leg encircling crane rotates while operation. This arrangement enables the rotation of the machine house of the crane boom along with the crane boom without entangling the hose, during the crane operation.

[0017] It is, therefore, another objective of the disclosed embodiments, the pedestal crane has a pedestal and a mast through which high pressure oil from the hydraulic power unit of the jacking system is routed through the rotary hose without any pressure drop during the rotation of machine house. This enables the passage of oil through the rotary hose when the machine house of the crane is rotating. [0018] It is, therefore, another objective of the disclosed embodiments to provide interconnected hydraulic power units on jacking system for movement of each support leg to provide back up for lifting and lowering device, such that when one hydraulic power unit is under maintenance or repair, the other hydraulic power units can be utilized to support the crane operation.

[0019] It is, therefore, another objective of the disclosed embodiments to initially use the hydraulic power units of the jacking system to elevate the platform and then use the hydraulic power units for crane operation from the elevated platform.

[0020] It is, therefore, yet another objective of the disclosed embodiments to provide SEWOP wherein the jacking system further comprises an electric motor and/or a diesel engine; and wherein the hydraulic power unit of the jacking system operates on power from the electric motor and/ or diesel engine when the lifting and lowering device requires high flow.

[0021] It is, therefore, yet another objective of the disclosed embodiments to provide for the hydraulic power units that are used to power a cantilever for work over operation.

[0022] It is, therefore, yet another objective of the disclosed embodiments to provide for a hose reel that houses sufficient hose length to enable predetermined number of rotations of the machine house around the lattice support leg, such that the machine house of the leg encircling crane rotates freely along with boom during required operation.

[0023] It is, therefore, another objective of the disclosed embodiments to provide a self-elevating work platform in which the leg encircling crane has a sensor for detecting the predetermined number of rotations around the lattice support leg, such that operator rotates the crane back to the original position once the lifting and lowering operation is completed or when the number of rotations exceeds the predetermined limit.

[0024] It is therefore another aspect of the present invention to provide a SEWOP which employs a method of using hydraulic power units of a jacking system for at least one crane operation in a self-elevating work platform comprising providing at least one hydraulic power unit for support wherein the hydraulic unit is connected at least one leg of the self-elevating work platform; providing at least one jacking system having at least one hydraulic unit with a manifold; comprising a valve block in a crane hydraulic system of a crane; interconnecting the hydraulic power units of the legs and valve block in the crane hydraulic system wherein the valve block is connected to a hose; and diverting high pressure hydraulic oil from the hydraulic power units of the legs to valve block of the crane hydraulic system through the hose

[0025] It is therefore another objective of the present invention to provide a method which employs routing high pressure oil from the hydraulic power units by the crane, through a rotary hose or a hose reel; and driving hydraulic motors of the crane to perform required operation.

[0026] Other aspects and advantages of the invention will become apparent from the following detail description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.

[0028] FIG. 1 is an illustration of a side view of SEWOP with pedestal cranes, in accordance with the disclosed embodiments;

[0029] FIG. 2 is an illustration of a top view of SEWOP) with pedestal cranes depicted in FIG. 1 in which the pedestal cranes are powered by the hydraulic power units of the jacking systems, in accordance with the disclosed embodiments;

[0030] FIG. 3 is an illustration of a top view of SEWOP with both pedestal and LEC in which the pedestal and LEC are powered by the hydraulic power units of the jacking systems, in accordance with the alternate embodiments;

[0031] FIG. 4 is an illustration of a simplified block diagram showing hydraulic power supplied from the hydraulic power units of the jacking system f the SEWOP for cranes, in accordance with the disclosed embodiments;

[0032] FIG. 5 is an illustration of a side view hydraulic power system providing high pressure hydraulic oil from the hydraulic power units of the jacking units till the machine house of the pedestal crane of depicted in FIGS. 2 and 3, in accordance with the disclosed embodiments; and

[0033] FIG. 6 is an illustration of a side view hydraulic power system providing the high pressure hydraulic oil from the hydraulic power units of the jacking units till the machine house of the leg encircling crane of FIG. 3, in accordance with the alternate embodiments. DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0034] The particular values and configurations discussed in these non-limiting examples can be varied and are cited merely to illustrate at least one embodiment and are not intended to limit the scope thereof.

[0035] It will be appreciated that variations of the above disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

[0036] Self-Elevating Work Platform (SEWOP) in which the hydraulic power unit of jacking system is provided to one or more legs. The each leg comprises a hydraulic power pack powered by the hydraulic power units. The power pack of the legs are interconnected. Further a crane is provided which is used for various operations such as lifting and lowering of goods. The cranes can be a leg encircling crane or a pedestal crane. The crane comprises a hydraulic power system, called crane hydraulic power system. The crane hydraulic power system comprises a valve block and a hydraulic motor. The valve block is connected to the hydraulic power unit of the jacking system. Further, the hydraulic power unit of the jacking system has a manifold from where hydraulic power is diverted to the valve block of the hydraulic system of cranes by diverting the high pressure hydraulic oil through a hard pipeline. The High pressure (HP) hydraulic pipeline is routed to the crane through a heavy duty rotary hose or hose reel which enables HP hydraulic oil supply to the hydraulic system of the crane irrespective of the crane rotation. The heavy duty rotary hose is installed on the top of the crane structure. In a leg encircling crane, the high pressure oil from the hydraulic power unit is routed through a hose reel which is mounted on top of the jack house. The high pressure oil is connected to the machine house through a ribust hose tray which has provision to lay the hose on itself without entangling. For example, when the crane machine house rotates along with crane boom during crane operation, the hose reel has capacity of 40 meters of the hose reel which shall enable three complete rotation of the machine hose around the leg. Further, there a sensor is provided which counts the number of rotation in either direction. Once the rotations reaches to three complete rotations, the sensor initiates instruction to stop further rotation in particular direction. The crane operator needs to rotate back the crane once the lifting work is done.

[0037] The diverting of power from the hydraulic power unit to the crane hydraulic system eliminates requirement of separate power system for the crane. Which further support green energy by removing requirement of diesel engine, reduces noise pollution significantly, simplifying the spare parts inventory as engine driven hydraulic power system for the crane is eliminated. Further, the capital cost and maintenance cost is also reduced significantly.

[0038] Additionally, the hydraulic power units available for the jack system for each support leg are linked to each other to provide back up for the crane operation. Thus, even if one hydraulic power unit is under maintenance, the power from the other hydraulic power unit can be used to support the crane operation.

[0039] Referring to FIG. 1, a side view of a Self Elevating Work Platform (SEWOP) 300 with pedestal cranes 303 is disclosed. The SEWOP 300 has a hull 301 with an upper work area thereon and lattice legs 304 attached to the hull 301. The lattice legs 304 are drilled inside the deep sea and are deployed in the seabed for supporting the SEWOP 300. The SEWOP 300 has two cranes 303 and each crane 303 is supported by a pedestal 350. The hull 301 or the platform structure has a helideck structure 307 on which a helicopter can be operated. The hull 301 further has propulsion system having at least one azimuth type thruster 302 on the open deck side and at least one propeller with rudder 305 on the below the helideck structure 307. The accommodation block 306 is the space available for an operational personnel and does not include machineries and equipment area. The hull 301 has rescue lifeboats

310 which are used to rescue crewmen and passengers in case of emergency, such as hazards at the time of handling the inflammable oil and gases. One end of the a cantilever 309 is attached to an end of a hull 301 and the other end of the cantilever 309 holds the Work Over Unit (WOU) 308 above the seabed for performing work over operations such as drilling oil wells.

[0040] FIG. 2 is an illustration of a top view of Self Elevating Work Platform (SEWOP) 300 with pedestal cranes 303 powered by the hydraulic power units 311 of a jacking system, in accordance with the disclosed embodiments. Each lattice leg 304 has a jacking system (not shown) for elevating and lowering the hull 301. The jacking system has hydraulic power units 311 which are powered by an electric motor (not shown). The jacking system is used for elevating the hull 301 at a predetermined distance by using the hydraulic power units 311. The jacking system and cranes 303 are not operated together and the cranes are normally operated after jacking operation. Thus, once the jacking operation is completed, the hydraulic power unit

311 of jacking system which is used for movement of support legs can be used for the operation of cranes 303. To improve the hydraulic power availability, the hydraulic power units 311 are provided on each support leg and interconnected using a hard pipeline 317 to provide back up for the crane operation. As shown in the figure, the hydraulic power units 311 are linked and then connected to the cranes 303 using the hard pipeline 317. From the hard pipeline 317, the high pressure hydraulic oil is supplied to the machine house 315 (shown in FIG. 5) of the pedestal cranes 303 through a rotary hose 322 (shown in FIG. 5).

[0041] FIG. 3 is an illustration of a top view of Self Elevating Work Platform (SEWOP) 300 with pedestal cranes 303 and LEC 343, in which the pedestal cranes 303 and LEC 343 are powered by the hydraulic power units 311 of the jacking systems. Each lattice leg 304 has a jacking system (not shown) for elevating and lowering the hull 301. The jacking system has hydraulic power units 311 which are powered by an electric motor (not shown). The jacking system is used for elevating the hull 301 at a predetermined distance by using the hydraulic power units 311. The jacking system and cranes such as pedestal cranes 303 and LEC 343 are not operated together and the cranes are normally operated after jacking operation. Thus, once the jacking operation is completed, the hydraulic power unit 311 of jacking system can be used for the operation of pedestal cranes 303 and LEC 343. To improve the hydraulic power availability, the hydraulic power units 311 are interconnected using the hard pipeline 317 to provide back up for the crane operation. As shown in the FIG. 3, the hydraulic power units 311 are linked and then connected to the pedestal cranes 303 and LEC 343 using the hard pipeline 317. From the hard pipeline 317, the high pressure hydraulic oil is supplied to the machine house 3 5 of the pedestal cranes 303 through a rotary hose 322 (shown in FIG. 5). The high pressure hydraulic oil from the hydraulic power units 311 of jacking system is also supplied to the machine house 315 (shown in FIG. 6) of the LEC 343 through a hose reel 424 (shown in FIG. 6).

[0042] FIG. 4 is an illustration of a simplified block diagram showing hydraulic power supplied from the hydraulic power units of the jacking system of the SEWOP for crane operation. The cranes can be a leg encircling or a pedestal type. The redundant power of hydraulic power units of jacking system is used for both jacking and crane operations as the cranes and jacks are not operated at the same time. As shown in the FIG. 4, the hydraulic power unit 311 supplies hydraulic power to the hydraulic motors 329, 330, 332 and 333 of main hoist, auxiliary hoist, boom position hoist and slew ring drive respectively through a control valve bank 338.

[0043] It should be noted that the hydraulic motors of crane are not powered by dedicated diesel engine or from main electric power supply, instead powered by the hydraulic power units of jacking system. If the hydraulic power unit for jack system is used for cranes, the usage of diesel engine is avoided thereby eliminating environmental pollution. By avoiding diesel engine and its associated hydraulic power unit, the dead weight of the crane is reduced which increases the variable deck load for the SEWOP and reduces stress on the support structure. [0044] FIG. 5 shows the pedestal crane 303 (shown in FIGS. 1 and 2) above the main deck 313 of the hull 301 , supplied with HP oil from the jacking system. Since the crane machine house 315rotates along with crane boom (not shown) during crane operation, the HP line needs to be routed through the rotary hose 322. The HP oil from the jacking system is supplied to the rotary hose 322 through the hard pipeline 317 which flows inside the pedestal 314 and mast 316 of the crane 303. From the rotary hose 322, the HP oil is routed to the machine house 315 by using another hard pipeline 319. The rotary hose 322 allows oil passage without any pressure drop, while the machine house 315 is rotating. Thus, the valve block (not shown) receives HP hydraulic oil from the power unit of the jack system on the main deck 313 through the hard pipelines 317 and 319 and the heavy duty rotary hose 322 which are installed on the top of the crane structure.

[0045] It should be noted that when the jacking operation of SEWOP is in progress, the cranes are not operated. The cranes are operated only when SEWOP is stabilized in the elevated mode, where the jack system is not operated. Thus the hydraulic power unit of jack system is available for the use of the crane. The manifold on the hydraulic power unit diverts the HP hydraulic oil to the valve block on the crane through the rotary hose. Once the HP hydraulic oil is available at the valve block, the crane can be operated as per normal operation. When high flow is required for the crane operation, the hydraulic power unit can supply the same by taking required power from the electric motor of the jacking system.

[0046] FIG. 6 is an illustration of a side view of hydraulic power system providing the high pressure hydraulic oil from the Hydraulic Power Units (HPUs) of the jacking units till the machine house 415 of the Leg Encircling Crane (LEC) 343 of FIG. 3, in accordance with the disclosed embodiments. The arrangement for supplying the HP oil to the pedestal crane 303 depicted in FIG. 3 is same as illustrated in the FIG. 5, whereas for the LEC 343, the arrangement is different from the pedestal cranes 303. The high pressure oil (HP) from the HPU is routed to the machine house 415 through a high pressure hose reel 424, a robust hose tray 425 and a hose 442 which are mounted on the top of the jack house 423. The high pressure oil from hard pipe line 317 is initially connected to the hose reel 424 and then to machine house 415 through the hose tray 425 which has a provision to lay the hose 442 on itself without entangling. When the machine house 415 rotates along with crane boom 414 during the crane operation, the hose reel 424 having the capacity of forty meters enables three complete rotation of the machine house 415 around the leg 304. The crane mast 416 and wire rope 421 are shown in FIG. 6.

[0047] In another embodiment, the crane has a sensor (not shown) and an inter link (not shown) to take care of the rotation of the crane 343 encircling the leg 304 and the length of the hose 442. The sensor counts the number of rotation of crane in either directions and the interlink stops the crane operation in response to the sensor information, when the crane is rotated more than three rotations around the leg in a direction. The crane operator needs to rotate back the crane once the lifting work is done.

[0048] It should be noted that the hard pipeline, rotary hose, hose reel and hose tray that supplies high pressure oil from the hydraulic power unit of jacking system to machine house of the crane can be made of suitable HP heavy duty material without any limitation. Thus, by using a self-elevating work platform in which the hydraulic power units of the crane are driven by electric motor of the jacking system, a quieter and cleaner SEWOP is obtained than cranes with diesel engines.

[0049] It should also be noted that the SEWOP can have one or more tubular or lattice legs and are fitted with Leg encircling cranes (LEC) and/or pedestal cranes without limitation. Further, the hydraulic power units of jacking system can be powered by electric motor or diesel engine or the electro-diesel engine combination. For the crane operation, the need for the dedicated electric motor or diesel engine and its hydraulic power units are eliminated, instead the hydraulic power units of jacking system powered by electric motor and/or diesel engine are used. [0050] Embodiments of the current disclosure have been described comprehensively, in considerable detail to cover the possible aspects, those skilled in the art would recognize that other versions of the disclosure are also possible.