摘要:
Apparatus and methods for remotely installing vortex-induced vibration (VIV) reduction and drag reduction devices on elongated structures in flowing fluid environments. The apparatus is a tool for transporting and installing the devices. The devices installed can include clamshell-shaped strakes, shrouds, fairings, sleeves and flotation modules.
摘要:
Methods for remotely installing vortex-induced vibration (VIV) reduction and drag reduction devices on elongated structures in flowing fluid environments. The devices installed can include clamshell-shaped strakes, shrouds, fairings, sleeves and flotation modules.
摘要:
A fairing system is disclosed for installation about a drilling riser deployed in a deepwater application. In another aspect of the invention, a method for deploying a drilling riser fairing system is disclosed in which a first retaining ring is installed on a buoyancy can encircling the drilling riser and a drilling riser fairings is installed above the first retaining ring. Drilling riser fairing installation folds a pair of fairing sides of a fairing shroud about an axially disposed hinge to surround the buoyancy can above the first retaining ring. A tail connection system secures the tail ends of the fairing sides together and a pair of struts are installed to further secure the fairing sides together. A plurality of interior bearing pads are provided on the internal circumference of the fairing shroud and axial bearing pads are provided on flanges at the upper and lower edges of the fairing shroud. In yet another aspect of the present invention, a method for stowing a drilling riser fairings is disclosed in which a lift harness is connected to lift eyes on the exterior of the fairing shroud and the tail connection system is released from the tail edge of the fairing sides. Struts are removed from the upper and lower flanges of the fairing sides which are then opened up about their hinged connection. The open fairing shroud is lifted and set down in a nested relationship with other removed fairing shrouds.
摘要:
Methods are presented for analysing semiconductor materials (8), and silicon photovoltaic cells and cell precursors in particular, using imaging of photoluminescence (12) generated with high intensity illumination (16). The high photoluminescence signal levels (16) obtained with such illumination (30) enable the acquisition of images from moving samples with minimal blurring. Certain material defects of interest to semiconductor device manufacturers, especially cracks, appear sharper under high intensity illumination. In certain embodiments images of photoluminescence generated with high and low intensity illumination are compared to highlight selected material properties or defects.
摘要:
There is disclosed a current tank system comprising a first current tank adapted to produce a first current in a first direction; a second current tank adapted to rotate to produce a second current in a second direction; a sample adapted to be exposed to the first current and the second current.
摘要:
Sensors, including fiber optic sensors and their umbilicals, are mounted on support structures designed to be retro-fitted to in-place structures, including subsea structures. The sensor support structures are designed to monitor structure conditions, including strain, temperature, and in the instance of pipelines, the existence of production slugs. Moreover the support structures are designed for installation in harsh environments, such as deep water conditions using remotely operated vehicles.
摘要:
A method for controlling drag and vortex induced vibration in a substantially cylindrical element by providing an ultra-smooth surface about the cylindrical element. The system for controlling drag and vortex induced vibration utilizes a substantially cylindrical marine element having an ultra-smooth effective surface.
摘要:
A partial helical strake system and method for suppressing vortex-induced-vibration of a substantially cylindrical marine element, the strake system having a base connected to the cylindrical marine element and an array of helical strakes projecting from the base for about half or less of the circumference of the cylindrical marine element.
摘要:
A method for reducing VIV is disclosed for a spar platform having a deck, a cylindrical hull having a buoyant tank assembly, a counterweight and an counterweight spacing structure. The overall aspect ratio of the hull is reduced by providing one or more abrupt changes in hull diameter below the waterline.
摘要:
The present invention is a method for deploying a drilling riser VIV suppression system in which a first retaining ring is installed on a syntactic foam buoyancy module encircling the drilling riser with a spring loaded connection. The spring loaded connection is capable of adjusting the diameter of the retaining ring automatically to compensate for compression of the syntactic foam under the influence of water pressure. VIV suppression provisions is then installed about the drilling riser using the first retaining ring as a load shoulder.