Abstract: A drill collar structure to facilitate measurement-while-drilling (MWD) techniques while at the same time having sufficient rigidity to facilitate the drilling operation is disclosed. In some embodiments, a metal structure involving openings such as slots, preferably oriented longitudinally along its axis, but also in other configurations, are disclosed to allow sufficient strength while at the same time allowing exit and entrance of electromagnetic energy. A composite structure is also disclosed which, for given layers, has adjacent fibers such as glass and carbon, so that when the layers are overlapped, glass areas overlap glass areas throughout the radial thickness of the composite tube to create “windows” for the entrance and exit of electromagnetic energy. In yet other embodiments, the drill collar can be made of a metallic frame structure with a multiplicity of openings which are filled with a composite material.

Abstract: A coated polymer material having a swollen polymer network and a coating formed by reacting at least two reactants in the presence of the polymer material is provided, wherein the coating is obtainable by contacting the polymer material, which encloses the one reactant diffusibly, with the second reactant in liquid medium.

Abstract: A method for the manufacture of tools and components for the offshore field and the mining industry, in particular for drilling installations using a spray formed Cu—Ni—Mn alloy consisting of 10 to 25% Ni, 10 to 25% Mn, the remainder being copper and the common impurities. Due to the favorable characteristic of the combination, it is suitable as a replacement material for Be-containing copper materials.

Abstract: An apparatus (1) for manufacturing a three-dimensional object (13) comprises a trough (7) for holding material (11) which can be solidified under the influence of light. The trough (7) comprises on its lower side a transparent plate (8). On the transparent plate (8) and side wall (10) of the trough (7) is provided a resilient layer (9) from which solidified material is easier to detach than from the transparent plate (8). An exposure and projection unit (19) serves to expose and solidify the material (11) in the trough (7) from below through the transparent plate (8).

Abstract: An apparatus and a method for the separation of a material layer (4) hardened on a flat plane (2) serving as a reference by means of a flexible, elastic separating layer (1) arranged between plane and material layer and designed in the form of a film or a gel-like material, are provided.