Abstract: A cantilever beam of a jack-up unit is provided with constant force restraining members mounted on a deck of a jack-up unit forward from conventional hold-down cantilever beam clamp. A modified cantilever beam end plate engages a first end of constant force restraining member, which may be a hydraulic cylinder, with the second end of the hydraulic cylinder secured to movable padeye, which is releasably secured to the deck of the jack-up unit. If desired a fixed foundation may be secured to the deck to reinforce the area of attachment of a padeye to the deck. To allow extension of the cantilever beam even farther to a drill well, an extension member may be attached to the end plate between a free end of the end plate and the hydraulic cylinders.

Abstract: A self-elevating drilling unit has dual cantilever assemblies that move longitudinally and transversely in relation to the jack-up platform to allow drilling operation to be performed from two drilling floors. The twin cantilever assemblies permit simultaneous drilling on an 8 feet×8 feet spacing. The cantilever assemblies are retained attached to the platform by a hold down beam that extends over and across the cantilever assemblies. The hold down beam is positioned in a stationary manner on the platform deck. A movable strut that engages the underside of the hold down beam moves along the beam to counteract upward bending forces acting on the beam when the cantilever assemblies are extended from the platform. The cantilever assemblies are made of tubular truss work and can be moved to an infinite number of horizontal positions.

Abstract: A self-elevating drilling unit has dual cantilever assemblies that move longitudinally and transversely in relation to the jack-up platform to allow drilling operation to be performed from two drilling floors. The twin cantilever assemblies permit simultaneous drilling on an 8 feet×8 feet spacing. The cantilever assemblies are retained attached to the platform by a hold down beam that extends over and across the cantilever assemblies. The hold down beam is positioned in a stationary manner on the platform deck. A movable strut that engages the underside of the hold down beam moves along the beam to counteract upward bending forces acting on the beam when the cantilever assemblies are extended from the platform. The cantilever assemblies are made of tubular truss work and can be moved to an infinite number of horizontal positions.

Abstract: A deep draft semi-submersible offshore structure suitable for conducting mineral exploration and production operations in deep waters of the oceans. The structure uses three or more caissons or columns equidistantly spaced from adjacent columns. The weight distribution and provision of liquid or solid permanent balance in the lower ends of each column make the structure stable without reliance upon water line displacement or tendons, as compared to conventional vessels. The center of gravity of the structure is maintained below its center of buoyancy, thus imparting an inherent absolute stability to the structure. The columns are retained in spaced relationship to each other by a plurality of horizontal braces or a combination of horizontal braces and diagonal braces. The major part of the structure is positioned below the water surface at sufficient depth to minimize the reaction to surface changes, thereby greatly reducing heave and angular response to surface wave action.

Abstract: A process for perforating material comprising the steps of advancing material along a path of travel, passing the advancing material over a movable laser mask having an aperture such that the material drives the mask in unison with the movement of the material, and directing at least one laser beam through the corresponding aperture so as to vaporize the material juxtaposed the mask aperture to correspondingly form an opening in the material. The apparatus contemplated for perforating the material as it is advanced along a path of movement comprises first means for advancing the material along the path of movement, second means having at least one aperture and being operatively associated with the first means for enabling the perforation of the material as it is advanced along the path, and for being driven by and in unison with the advancing material, and third means operatively associated with the second means for vaporizing material juxtaposed said aperture.

Abstract: Disclosed is a method and apparatus for perforating cigarette tipping paper which holes may be obvious or which may be so small as to be "non-obvious". The holes produced range upward from about 0.025 mm. (0.001") or 0.051 mm. (0.002") and are rectangular. As shown in FIG. 4 the web (40) of tipping paper is moved in the direction of the arrow (44) about idler rolls (82) and in contact with at least one rotatable mask (100). The web (40) is in contact with the outer peripheral surface of the cylindrical wall of the masks (100) over a small area (90). The masks (100) are driven, usually at a greater linear rate of speed, in the opposite direction as indicated by the arrows (122) with respect to the movement (44) of the web (40). A laser beam (140) is projected against the interior surface of the cylindrical wall of the masks (100) in alignment with elongated slots (128, 132) which slots (128, 132) extend through the cylindrical wall of the masks (100).