Abstract: A speaker assembly for good thermal management in loudspeakers such as planar magnetic drivers (PMDs). The assembly comprises a front panel with one or more sound openings, one or more PMDs each associated with a respective sound opening, one or more rear thermal plates each associated with a respective PMD structure plate, and a thermal spreader plate. The PMD structure plate is mounted to the front panel, the rear thermal plate is mounted to the associated PMD structure plate, and the thermal spreader plate is mounted to the one or more rear thermal plates, thereby forming a layered heatsink assembly. In a further development, the assembly has multiple PMDs and a circuit configured to modulate power handling and frequency response between the multiple PMDs.

Abstract: A shallow water flow subsea drilling system is disclosed. A wellhead system is provided with a 36″ conductor pipe in which a 26″ casing and 26″ wellhead housing are landed. The 26″ casing extends to a depth above a shallow water flow zone. A borehole through the shallow water flow zone is sized to accept a 20″ casing to the top of which is secured an 18¾″ wellhead housing. An annulus between the 26″ and 18¾″ housings communicates with cement returns from the 20″ casing. Flow-by holes in the 26″ wellhead housing are sealed with a retrievable seal assembly and actuating mechanism run on the same running tool with the 20″ casing and 18¾″ wellhead housing. A hydraulic feedback mechanism is provided to sense at the service vessel whether or not the seal assembly has been correctly positioned in the annulus.

Abstract: A running tool for use with a subsea well guide base when drilling from a floating drill ship is designed to be releasably detached without rotation so that the tool can be uncoupled at the surface upon completion of the guide base running procedure. The running tool is attached to the guide base by threaded elements which are designed to strip when a predetermined upward force is exerted on the running pipe string to which the tool is integrally connected thereby permitting retrieval of the tool by the running string.

Abstract: A retrievable guide base and gimbal unit for a subsea well, and a tool for use with a pipe running to retrieve the guide base and gimbal from the subsea wellhead.