Patent Application
20140262562
The present disclosure is directed to walking systems, large machines operable for transporting massive and heavy loads, upwards of thousands of tons, over a surface area, such as the ground, snow, gravel or sand, etc. Walking systems are designed as non-wheeled power-driven vehicles fabricated from iron and steel. They find particular utility in carrying and sequentially transporting huge structures such as oil drilling rigs and their support or service modules to pre-drilled, ground-installed conductor pipes. This is done prior to drilling well bores in fields undergoing oil exploration, or over existing well bores in previously-worked old fields, or the like.
The present disclosure is directed to a walking system and its substructure for transporting heavy machinery or equipment from one location to another, and more particularly to a walking system which can be moved along a straight line or also steered. The walking system can be steered so that it is displaced to align or orient equipment such as a drilling rig, precisely above a well bore, or move to another area entirely.
There are numerous examples of walking machines and systems which have been designed for use in moving drilling rigs for positioning over well bores during oil exploration. An example of a known walking machine is disclosed in U.S. Pat. No. 6,581,525 where a load-carrying transport apparatus for moving a heavy load, such as an oil drilling rig, over a surface includes a substructure for carrying the load, a track member positioned on the surface adjacent the substructure and a plurality of lift assemblies mounted on the substructure selectively operable for extension toward the surface to engage the track member and raise the substructure above the surface so that it is carried on the track member. The lift assemblies are also operable for retraction to lower the substructure onto the surface.
A shifter mechanism disposed adjacent to the substructure and the track member is selectively operable for displacing the substructure along the track member when the lifting assemblies have been extended toward the surface to raise the substructure above the surface. The shifter mechanism is also operable for displacing the track member on the surface relative to the substructure when the lifting assemblies have been retracted and disengaged from the track member. The track member is dimensioned to provide a steering area and at least one of the lifting assemblies is selectively positionable to a predetermined angle within a range for moving in the steering area along the track member so that the load-carrying apparatus can be steered along a selected direction.
Another example of a walking machine is disclosed in U.S. Pat. No. 5,921,336 in which a drilling rig substructure is provided with a plurality of lifting jacks, and each lifting jack is connected to a jack pad. Roller assemblies are mounted at the lower end of the lifting jacks and each jack pad has a center beam that the roller assemblies engage. The jack pads are rotatable in 360° about a vertical axis. A push-pull mechanism extends between each jack pad and each roller assembly to move the rollers horizontally in relation to the jack pad. In operation, when it is desired to move to a well bore, the lifting jacks are extended, forcing the jack pad against the ground.
Continued extension causes the upper end of the lifting cylinder to raise the substructure and accompanying drilling rig to move from ground level. The lifting jacks now remain in the extended position and the push-pull mechanisms are then actuated to move the substructure in a given direction. The lifting jacks are then retracted so that the substructure returns to the ground and the jack pad is then raised and moved to a new position.
A further example of the prior art is U.S. Pat. No. 7,819,209 which describes a guided transport unit for moving a superstructure in angular movements over a surface. There is disclosed a skid pad, a vertical displacing member engaged with the skid pad, a base operatively associated with the vertical displacing member, and a directional actuator. The base includes a planar element for engaging the surface over which the superstructure is transported, and a carrier for moving the vertical displacing member and skid pad relative to the surface. The disclosure shows that the side walls of the skid pads are provided with openings to enable the guided main structures to pivoted to extend at least partially outside of the skid pads.
The present disclosure is directed to a walking system and its substructure for transporting heavy machinery or equipment from one location to another, and more particularly to a walking system which can be moved along a straight line or also steered. The walking system can be steered so that it is displaced to align or orient equipment such as a drilling rig, precisely above a well bore, or move to another area entirely.
As noted above, the present disclosure is directed to a walking system for moving a load over the ground constructed as a substructure including a pair of spaced-apart, rigidly interconnected main beams, often referred to as “skids.” The main beams form the lower part of the substructure, and the entire arrangement may be raised above the ground and transported, carrying the load, in a preselected or given direction by means of a plurality of lifting jack assemblies.
The present disclosure contemplates such a walking system in which a jack support beam is mounted on top of each main beam on opposite ends thereof, and a lifting jack assembly is mounted on each jack support beam to extend downwardly therefrom. Each lifting jack assembly incorporates a power-driven hydraulic cylinder having a ram with a ground-engageable foot plate. The power-driven cylinders are selectively operable for extending their associated rams downwardly to force the foot plates against the ground to raise the substructure as a unit off the ground. The power-driven cylinders may be actuated to retract their rams to disengage the foot plates from the ground, thereby lowering the substructure onto the ground. A shifter mechanism is mounted on each lifting jack assembly selectively operable for displacing the substructure along the ground when the power-driven cylinders have been actuated to extend the rams to raise the substructure above the ground.
In accordance with the disclosure presented here, each jack support beam mounted on a main beam includes an extended end or outboard section projecting outwardly from the end of its associated main beam. The outboard section is arranged for supporting a lifting jack assembly in its entirety, including its power-driven cylinder, ram, foot plate and shifter mechanism outwardly from the end of its associated main beam. This is accomplished by designing each jack support beam to be mounted as a cantilever on its associated main beam. Further, this construction enables the outboard section to be inclined relative to the long axis of the main beam-mounted jack support beam.
The service module, supported on a substructure separate from that of the drilling rig, provides the necessary auxiliary equipment for the drilling rig. This equipment includes engines, pumps, motors, pipe storage, fuel, and mud pumps, to name a few, necessary for operating the drilling rig. The service module is interconnected with the necessary hoses, pipes, electrical conduits, etc. to the drilling rig. The service module and drilling rig each have an operator's cab, so that the operators of these two massive modules can control the necessary positioning of their respective substructures and loads. The drilling rig and service modules can together weigh upwards of 4-5,000 tons.
As stated at the outset, the present disclosure is generally directed to a walking system for moving a load over the ground, and is constructed as a substructure supported by two main beams. As shown in the side view of
While not shown in either
A plurality of steerable lifting jack assemblies are operable for lifting the main beams and substructure and raising them with their corresponding loads above the ground, and for lowering them as well. The entire substructure, main beams inclusive, may be raised above the ground and transported, carrying the load, in preselected or given directions by means of the lifting jack assemblies, which are indicated generally at 26 and 28 mounted on main beam 14, and 30 and 32 mounted on main beam 16 (see FIG. 2). Because each lifting jack assembly is essentially the same, reference will be directed to principally to the construction of lifting jack assembly 26 shown mounted on the left end of main beam 14, and also shown in the enlarged views of
Lifting jack assembly 26 is mounted on a jack support beam 32 to extend downwardly from an extended end or outboard section 34 of support beam 32 to project outwardly from the end of its associated main beam, such as main beam 14. The combination of the support beam and the jack lifting assembly functions as a lifting mechanism, as will be described. The outboard section is constructed for supporting lifting jack assembly 26 in its entirety so all the components making up the lifting jack assembly are spaced outwardly from the end of the main beam aligned along its longitudinal axis. This is accomplished by mounting support beam 32 as a cantilever beam on main beam 14 with its outboard section creating a moment about the pin connections, shown at 33 and 35. The manner of installing the pin connectors will be described later. The outboard section is inclined relative to the long axis of the main beam and the jack support beam.
Lifting jack assembly 26 incorporates a power-driven hydraulic cylinder 36 operable for extending and retracting a ram 38. Mounted on the end of ram 38 is a foot plate assembly, generally indicated at 40, and a roller assembly 42 is mounted on the end of the ram engaging the top surface of a ground-engageable foot plate 44, enabling relative travel (see
All four of the power-driven cylinders are selectively operable for simultaneously extending their associated rams downwardly to push the foot plates against the ground to raise the main beams and substructure 22 as a unit off the ground. The power-driven cylinders may be actuated to retract their rams to disengage the foot plates from the ground, thereby lowering substructure 22 onto the ground. A pair of shifter mechanisms are mounted on each lifting jack assembly, each with its own hydraulic travel cylinder and rod arrangement. As shown in
The shifting mechanisms may be operated to extend their rods, so that in the view of
As shown in the top plan view of
The method of mounting the jack support beams and their associated lifting jack assemblies onto a main beam is straight forward and efficient, and is accomplished generally in the following fashion, with attention directed to jack support beam 32 as an example. Initially, jack support beam 32 is fabricated but is not connected with its preassembled, corresponding lifting jack assembly, such as that shown at 26. A crane is attached to the eyelets or “pick points” shown at 72 and 74 secured on the top of the jack support beam, and lifts the unit into position above a receiving main beam such as that indicated at 14 to align holes in brackets or lugs 76 and 78.
These holes are shown at 76a and 78a, respectively, and they are to be aligned with corresponding holes in lugs 41 and 43 (see
With the lugs now in properly aligned position, the jack support beam is lowered onto the lifting jack assembly which has been placed on a support, such as the ground. Lowering continues until the bottom of mounting plate 70 engages the top of power-driven cylinder 36. At this juncture, bolts 71 are attached to interconnect power-driven cylinder 36 to mounting plate 70, completing the mounting of jack support beam 32 onto lifting jack assembly 26. This entire unit now can be lifted by the crane into position on top of main beam 14, and shifted until the lugs on the jack support beam are realigned with the lugs on the main beam. The pin connectors are now driven in, and the support beam and lifting jack assembly are now fully installed. This is the general method of how each of the four jack lifting assemblies are mounted on the jack support beams with the resulting unit then being attached to a main beam.
The walking system of the present disclosure is designed to enable steering, while the load is distributed over the ground, in a selected one of multiple modes, namely, longitudinal steering, simple steering, transverse steering, complementary steering, crab steering and circular steering. To implement the orientation necessary for each of these steering or traveling modes, the lifting jack assemblies must be raised so that their foot plates disengage from the ground. In this position the main beams and substructure and load will be entirely supported on the ground, with bearing pressure applied downwardly through the main beams onto the ground Next, the lifting assemblies are actuated to orient the foot plates in the desired steering mode, i.e., longitudinal steering, simple steering, etc.
In the next step the lifting jack assemblies are actuated to extend the rams downwardly to position the foot plates so that they engage the ground. Further extension of rams downwardly raises the main beam, and the entire weight of the main beams, substructure and load, be it from a drilling rig, or service module is now transferred directly onto the ground through the foot plates.
In this position, with the mode of steering having already been predetermined, the travel cylinders are actuated simultaneously as a group to displace or shift the main beam, the substructure and load relative to the foot plates, all of which remain stationary. When the travel or displacement has been completed, the jack lifting assemblies are actuated to lower the main beams onto the ground, and further retraction frees the foot plates from engaging the ground. The sector plate of the steering assembly may be selectively repositioned in the steering mode anticipated for the next direction that the walking system will take. And after operations, such as drilling, etc. have been completed, the lowering of the repositioned foot plates may begins and the process repeated.
From the above description, it should be appreciated that the present disclosure provides a walking system enabling heavy loads to be readily displaced and precisely turned to be positioned over a relatively small area, such as a conductor pipe at an oil drilling site. An advantage resides in the relatively simple construction which provides substructures for carrying and transporting a pair of loads, such as a drilling rig and a service module.
Still a further advantage in the present invention resides in the specific construction of the jack support beam, formed as a cantilever with an extended end or outboard section for mounting a lifting jack assemble and its associated foot plate close to, but away from the end of a main beam or skid. In this position, the foot plate has room to be positioned in a preselected steering mode, when the foot plate has been raised above the ground. The jack support beapa steering system which enables a pair of heavy loads, such as a drilling rig and a service module, to travel in a selected direction with the relative positions substantially maintained. This finds particular importance because the drilling rig and service module have interconnected equipment; the service module provides electricity, a source of mud for the drilling, gas, etc. to the drilling rig, and these connections must be maintained during transport of the respective substructures. The simplicity of the substructures, which includes the main beams, the lifting assemblies, the sub beams and the steering mechanisms, enables the relative positioning to be maintained, both in straight line travel and travel in which the units are steered.
