Abstract: A lightweight ROV deployable tree cap (28) for deployment on a subsea production hub (10) of a subsea tree. A tree cap (28) has a lightweight body (30) with parallel planar sides and including suitable openings and slots for mounting of the various operating elements. A seal plate structure (64) includes a piston (66) connected to a seal plate (68) having a pair of downwardly projecting tubular seal members (70, 72) for fitting within the production bore (13) and annulus bore (15) of the tree hub (10) in a sealed landed position. Fluid pressure is applied to fluid line (96) to urge piston (66) and seal plate (68) downwardly into sealing landed position. For removal or retrieval of tree cap (28) from the installed position on subsea tree hub (10), fluid pressure is applied through fluid lines (108, 110) for the upward movement of seal plate (68) and tubular seal members (70, 72) from sealing relation with production bore (13) and annulus bore (15).

Abstract: A radially locked subsea housing includes a low pressure housing having upper and lower radial lock regions, each of which regions includes a radial interference surface that is between vertical to only slightly tapered in orientation. A high pressure housing also has upper and lower radial lock regions, each of which regions includes a radial interference surface that is slightly greater in radial diameter than the corresponding interference surface of the low pressure housing. The interference surfaces of the upper and lower radial lock regions form upper and lower interference fits, respectively, between the high pressure and low pressure housings when the housings are assembled subsea.

Abstract: A borehole conditioning tool suitable for use in a drill string, the tool including a tubular body portion having a plurality of elongated, circumferentially spaced retainer slots for housing wall contacting members, each retainer slot being defined by a pair of opposed elongated slot side walls and a plurality of wall contacting members in the form of elongated stabilizer blades which are mounted in the retainer slots, each stabilizer blade having a pair of opposed blade side walls. In the borehole conditioning tool the slot side walls and blade side walls are shaped so that for each stabilizer blade one blade side wall is in engagement with one slot side wall, while the opposed blade side wall is in engagement with the opposed slot side wall along only a portion of the length of the blade side wall in at least one interference zone, the degree of interference being sufficient to locate the blade in position in the slot.