Patent Application
20060243527
There are no related patent applications.
The subject matter of the present invention did not receive federal government research and development funding.
The present invention generally relates to a device for suspending scaffolding comprising planking that supports workers, equipment and/or materials. More specifically, the invention relates to a suspended scaffolding system and device that comprises a first end for accepting an anchorage and a second end coupled to the first end and electrically insolated therefrom for attaching to an end of a cable or rope wire to support a planking therefrom. The present invention is useful in providing scaffolding that may be electrically isolated from a hull of a ship or other such structure to aid in marine construction, repairs and the like of the ship or structure.
Marine hanging staging (MHS) is a type of a tier, level or temporary elevated platform that supports workers, their tools and supplies. MHS is commonly used in shipyard operations to readily configure a support platform that may accommodate a variety of hull configurations and sizes. Typically, MHS is configured to be used by workers to perform abrasive blasting, welding and painting work on a hull surface of a vessel or other structure. The staging is typically rigged as paired assemblies of wire rope or suspension cables hung from overhead anchorages such as those known in the art as pork chop anchorages and s-hook anchorages. Rope walkers construct the MHS system by installing anchorage attachments and suspension cable assemblies in holes on an overhead structural steel support of a vessel or tank. Struts are attached to the pairs of wire rope at various heights to support planks that support workers, equipment and/or materials
Failure of a MHS system is a major concern to ship repair workers. Should the MHS system fail, the workers may fall great distances resulting in injury or death. Previously, MHS systems have failed when the structural integrity of the wire ropes were compromised. One such failure occurred when a stray current from a welding machine passed through a wire rope. The diameter of the rope was unable to adequately pass the stray current to ground and the structural integrity was compromised causing the rope to be unable to support the load applied between the planking and the anchorage. A failure of the MHS system occurred resulting in injury to the workers.
The invention is aimed at providing a device for anchoring a MHS system to anchorage points while electrically isolating the system from the hull of the ship to prevent stray currents from passing through the wire rope which may result in structural failure of the wire rope and collapsing of at least a portion of the MHS system.
The hanging device includes a first end for accepting an end of an anchorage and a second end for accepting an end of the support cable or shackle attached thereto to provide support for a rope wire that attaches to a planking that is part of a MHS system. The first and second ends are coupled together via a coupling means that electrically isolates one end from the other.
In a first embodiment, an eye bolt having an opening and a threaded extension comprises a first end of the hanging device. The threaded extension passes through and is threaded into a threaded opening in a first eye nut. The first eye nut includes a second opening through which a coupling means passes to secure a second end to the first end. Typically, the coupling means is a nylon strap that has electrical isolative properties while having a tensile strength great enough to support a portion of the MHS. A block of insulator material is disposed between the first eye nut and a second eye nut coupled to a second eye bolt that comprises the second end. The nylon strap and block of insulator material serve as a coupling means between the first and second eye nuts.
Thus, the present invention comprises a hanging device that includes two ends that are coupled together. The ends are electrically isolated from one another to create a hanger that can couple a plank to an anchorage without electrically coupling the plank and anchorage such that they may be maintained at electrical differences. That is to say the anchorage point and the MHS system may be electrically isolated from one another. Thus the hanging device acts as an insulator between the structure and suspension cable to prevent cable embrittlement caused by stray currents passing through the rope wire.
The size and shape of the hanging device lends itself to being readily used by rope walkers during the installation process of the MHS system. A plurality of hanging devices may be clipped onto a belt or rope and easily carried by a rope walker. Since the first and second ends are substantially similar in shape, the rope walker can readily deploy the hanging devices without concern for a proper orientation of the devices. When the rope walker reaches a desired location, a hanger may be readily deployed and secured at one end to an anchorage and at a second end to a rope wire that is coupled to a plank.
It is an object of the invention to provide a suspension cable assembly that comprises a hanger that electrically isolates a MHS system from a support structure. The hanger provides an electrical insulation between the hull of the vessel or structure upon which work is being performed and the MHS system to prevent electrical currents from passing through suspension cables.
It is a further object of the invention to provide a hanger that can be easily deployed and used to support a MHS system. In one instance, the hanger supports a load of over four thousand pounds.
It is a further object of the invention to provide a hanger that comprises a first end and a second end for receiving an anchorage and a support cable, respectively. The first and second ends are coupled to one another by a coupling means. The coupling means exhibits electrical insulative or isolative characteristics.
It is a further object of the invention to provide a hanger that is rugged and remains in tact and does not severely degrade during sandblasting and other necessary marine construction operations.
These and other objects of the invention will become apparent to those skilled in the art upon review of the following drawings and appended claims. Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned from practicing the invention. The objects and advantages of the invention will be obtained by means of instrumentalities in combinations particularly pointed out in the appended claims
In
A second threaded portion 5B of a second eyebolt 3B is threaded into a portion of the second eye nut 9B. One of the through holes, 7A or 7B accepts a first fastening device, not shown, for attaching the hanger 1 to an end of a suspension cable 102; while the other through hole, 7A or 7B accepts a second fastening device to couple the hanger 1 to an anchorage point, not shown.
It is to be understood that the invention is not limited to the exact construction illustrated and described above, but that various changes and modifications may be made without departing from the spirit and the scope of the invention as defined in the following claims.
