Abstract: A drilling assembly for downhole to surface communications is provided. The drilling assembly includes a series of pipe segments coupled in fluid communication between a slip ring assembly and an end pipe portion. The slip ring assembly is coupled in data and fluid communication with the pipe segments. A surface communications link is in data communication with the drilling assembly via the slip ring assembly. An end pipe portion is coupled with the drilling assembly that includes an electronics assembly with electronic components for transferring data to the slip ring assembly via the drilling assembly. A drill bit is operably coupled with the end pipe portion for drilling a borehole. Each pipe segment includes an outer conductor portion, a hollow inner conductor portion, and a dielectric portion for electrical isolation between the outer conductor portion and the inner conductor portion.

Abstract: A method is described for installing a stud to extend above a surface of a composite portion of a tank or other structure subject to the pressure of cryogenic fluid, so that another structure can be attached to the stud. The method includes drilling a through aperture at the location of the stud, and installing a threaded insert near the outer surface of the aperture, if not already installed. A metal bolt having a CTE less than that of the composite material is selected. The bolt has an unthreaded shank portion and a threaded portion. The length of the bolt exceeds the length of the projecting stud and the thickness of the composite. The bolt is assembled with a commercial k seal, a collar having a CTE much less than that of the bolt, and another k seal. The seals mate with corresponding frustoconical surfaces of the composite and of the collar, and when the bolt is properly torqued to a preload, prevent leakage.

Abstract: A method is described for installing a stud to extend above a surface of a composite portion of a tank or other structure subject to the pressure of cryogenic fluid, so that another structure can be attached to the stud. The method includes drilling a through aperture at the location of the stud, and installing a threaded insert near the outer surface of the aperture, if not already installed. A metal bolt having a CTE less than that of the composite material is selected. The bolt has an unthreaded shank portion and a threaded portion. The length of the bolt exceeds the length of the projecting stud and the thickness of the composite. The bolt is assembled with a commercial k seal, a collar having a CTE much less than that of the bolt, and another k seal. The seals mate with corresponding frustoconical surfaces of the composite and of the collar, and when the bolt is properly torqued to a preload, prevent leakage.

Abstract: A method is described for installing a stud to extend above a surface of a composite portion of a tank or other structure subject to the pressure of cryogenic fluid, so that another structure can be attached to the stud. The method includes drilling a through aperture at the location of the stud, and installing a threaded insert near the outer surface of the aperture, if not already installed. A metal bolt having a CTE less than that of the composite material is selected. The bolt has an unthreaded shank portion and a threaded portion. The length of the bolt exceeds the length of the projecting stud and the thickness of the composite. The bolt is assembled with a commercial k seal, a collar having a CTE much less than that of the bolt, and another k seal. The seals mate with corresponding frustoconical surfaces of the composite and of the collar, and when the bolt is properly torqued to a preload, prevent leakage.

Abstract: A joint between materials having disparate coefficients of thermal expansion (CTE) is compensated by a collar which extends a dimension of that one of the different materials which has the lesser CTE. A set of different collars provides compensation for sheets of material of different thicknesses when used with fasteners of a given material. The joint is assembled by selecting the sheets of various thicknesses to be juxtaposed, applying the fastener with a compensation collar corresponding to each one of the different sheets, and tightening the joint.