Abstract: Provided is an enclosed derrick structure of an arctic ship, which provides an installation space for an exhaust unit at an upper portion of an enclosed derrick. The enclosed derrick structure of the arctic ship includes: an enclosed derrick; a crown block section disposed at an upper portion of the enclosed derrick such that a crown block is installed and an installation workspace is formed thereinside; and an exhaust unit installed in the installation workspace to communicate with the exterior.

Abstract: Provided is a damping apparatus for a moonpool, which has a simple driving mechanism. The damping apparatus includes one or more damping plates which cover a moonpool of a hull entirely or partially. The damping plates are pivotally hinged to a sidewall of the moonpool, and one or more conveying units are disposed above the moonpool to convey drilling equipment. Driving wires are coupled between the conveying units and the damping plates, and the conveying force of the conveying units is transferred through the driving wires to the damping plates. Thus, the damping plates are pivoted to open and close the moonpool entirely or partially.

Abstract: Provided is a damper structure for an enclosed derrick, which can constantly compensate and maintain a pressure of an inner space of an enclosed derrick structure. The damper structure for the enclosed derrick includes: one or more communication ducts installed in a side of the enclosed derrick; and one or more open/close dampers coupled to the communication ducts to open or close the communication ducts, whereby air is selectively supplied to or exhausted from the enclosed derrick.

Abstract: Two sensors may be installed on a marine drill to improve measurements used for monitoring and operating the marine drill. The sensors may be installed in a differential configuration with one sensor located on a top block of the marine drill and a second sensor located on a drilling floor of the marine drill. Various calculations may be performed using measurements obtained from the two sensors such as, for example, rate of penetration of the marine drill, drilling level bubble for the marine drill, out of-straightness values for the marine drill, and vibration motion for the marine drill.

Abstract: A hybrid power plant is characterized by a substantially constant load on generators regardless of momentary swings in power load. Short changes in power load are accommodated by DC components such as capacitors, batteries, resistors, or a combination thereof. Resistors are used to consume power when loads in the power plant are generating excess power. Capacitors are used to store and deliver power when the loads in the power plant demand additional power. Reducing rapid changes in power load as seen by the generators allows the generators to operate at higher efficiencies and with reduced emissions. Additionally, power plants employing combinations of generators, loads, and energy storage devices have increased dynamic performance.

Abstract: A hybrid power plant is characterized by a substantially constant load on generators regardless of momentary swings in power load. Short changes in power load are accommodated by DC components such as capacitors, batteries, resistors, or a combination thereof. Resistors are used to consume power when loads in the power plant are generating excess power. Capacitors are used to store and deliver power when the loads in the power plant demand additional power. Reducing rapid changes in power load as seen by the generators allows the generators to operate at higher efficiencies and with reduced emissions. Additionally, power plants employing combinations of generators, loads, and energy storage devices have increased dynamic performance.

Abstract: An improved DC bus regulator that utilizes more transistor packs for power conversion at some times and diode, SCR, and resistor packs at other times. The conversion technology is selected by the regulator based on the current load capacity and response required. For example, transistor packs may be used in low power load conditions. Through use of this hybrid system, the system obtains the desirable effects of transistor pack systems including fast response time, ability to regulate current, and bi-directional power conversion while mitigating the high costs and fragile nature of a system based solely on transistor packs.

Abstract: A drilling system employing a main tubular having a plurality of fluid inlet and outlet conduits positioned thereon and a concentric inner tubular having a plurality seals for sealing the annular space between the concentric inner and main tubulars. The fluid inlet and outlet conduits work in cooperation with the annular seals to selectively open and close for effective management of pressure within the tubulars.