To inspect for cracks, workers lower this remotely operated vehicle, equipped with a video camera, into a pipeline of a hydroelectric plant in Peru.

To inspect pipelines for cracks and remove obstructions, Deep Ocean Engineering in San Leandro, Calif., designed the Pipeliner II remotely operated vehicle for oil-exploration firms, water- treatment plants, and water authorities.

The Pipeliner II is inserted into a pipe through a service port while an operator commands the vehicle from a control console. Commands are transmitted to the Pipeliner II by a neutrally buoyant umbilical cable made of reinforced Kevlar and a polyurethane jacket to make the cable waterproof. The umbilical contains multiple spare conductors for future applications.

Two electric motors, each capable of 11/3 horsepower, power two horizontal thrusters. A 1/4-horsepower motor provides vertical thrust for the vehicle. These thrusters use propellers, so the vehicle can glide forward, backward, vertically, and from side-to-side like a submarine in the pipeline. The propellers replace the wheels or treads used on competitive pipeline inspection vehicles.

The Pipeliner II provides a maximum bollard pull thrust of 100 pounds, even at the end of its 4,200-foot tether. The design overcomes the voltage loss - and thus the power loss - that typically results over long cable lengths. Most pipeline inspection vehicles have a maximum length of 500 feet.

The remotely operated vehicle can be equipped with an optional Simrad OC 1385 pan/tilt/rotate camera that transmits video images back to a television monitor by multimode optical fibers in the umbilical cable. An optional robotic arm can be attached to the new vehicle, enabling it to remove obstructions from within the pipeline. A compact frontal cross section measuring 18 inches wide by 17 inches high enables the Pipeliner II to inspect round pipelines as small as 20 inches.

Kadinger Marine in Milwaukee used the Pipeliner II to inspect the freshwater intake inside a Midwestern water-treatment facility during harsh weather last November. The vehicle sent clear images despite the high turbidity of the water, according to the company, and made its way easily through the 36-inch-diameter pipeline even though its walls were lined with zebra mussels.

The SpectraScan system consists of a focal-plane array and a lens assembly that records infrared imagery. It is also equipped with a tunable filter module that selects the wavelengths of light transmitted through the lens to the focal plane. The filter is a special configuration of a Fabry-Perot interferometer with high spectral resolution and broad wavelength tunability.

SpectraScan's spectral and spatial resolutions are high enough to detect and locate molecular species against various backgrounds and against structured atmospheric transmission.

The Idaho National Engineering Laboratory in Idaho Falls will use SpectraScan to identify and spatially map the level of contamination produced by volatile organic compounds, as part of the lab's Buried Waste Integrated Demonstration Program. SpectraScan is especially adept at detecting a broad range of compounds at one time. Possible uses for this technology include chemical processing and petrochemical refining.

The new BTL-3 transducer is equipped with a magnetic positioner that moves either along an external guide or over a rod. Through magnetostriction, the magnet induces a positioning signal in a filament within the transducer body. A microprocessor-based circuit linearizes this output signal, enhancing transducer positioning accuracy over the longest stroke lengths of pistons.

Because signal processing and serial conversion are performed internally, there is no need for a separate, external processor card, so the BTL-3 can be connected directly to the host controller. In addition, the absolute output signal renders the transducer immune to power failures, eliminating the need to reset the device mechanically after an outage.

The new transducer uses a synchronous serial interface format supported by most major controllers, including those involving numerical control. For example, the Rexroth Corp.'s Machine Tool Group in Lehigh Valley, Pa., combines the BTL-3 with its own Indramat four-axis closed-loop motion numeric control, proportional valve, and proportional-valve numeric-control amplifier card to create the Computerized Numerical Control Hydraulic Axis package. This package is used in applications that require the speed and power of hydraulics with numeric-control programmability and absolute position feedback, such as drill heads on automotive transfer lines, programmable grippers and fixtures, and metal feeding and forming.

A Teflon coating and a specially designed cable protect the sensitive optical fiber of the DHV video system when it is lowered into oil and gas wells.

Service firms for oil and gas exploration companies are using downhole video systems designed by DHV International Inc. in Ventura, Calif., to locate well-casing cracks and splits, guide the removal of broken downhole equipment, and detect fluid entry into oil and gas wells. The Halliburton Energy Services Division of Halliburton Co. in Dallas, for example, employs the DHV video system to inspect oil wells for clients, including Arco, British Petroleum, Chevron, Mobil, Oryx, and Shell.

The DHV system's video camera and lights are located at the end of a cable that is lowered into an oil or gas well. Real-time images captured by the camera are transmitted to the surface via an optical fiber. This fiber is coated with Du Pont's Teflon fluoropolymer to protect it from operating temperatures of up to 257degF. The coated fiber is sealed in stainless-steel tubing that is enclosed in two thermoplastic jackets, a braided copper conductor that supplies power to the camera and lights, and two layers of armor wire.

Because optical fiber provides much more bandwidth than coaxial cable, the DHV system provides more detailed images to the surface. In addition, optical-fiber transmission has nearly doubled the depth and pressure capabilities of the underground video system over coaxial cable-based video systems to 17,000 feet and 10,000 pounds per square inch, respectively. The video system has been used to inspect oil and gas wells in a wide variety of petroleum-producing regions, including Alaska, Australia, Brazil, Germany, Nigeria, Norway, Saudi Arabia, Scotland, and Trinidad.

Rather than using mercury-vapor or microwave sources, the new circular UV lamp incorporates a quartz source to provide both UV and visible light. Pulsed UV, according to Xenon, offers such advantages as a higher degree of cure, greater light penetration, low heat, and instant on/off capability.

Customized versions of the lamp can offer peak power levels of up to 10,000 watts per square centimeter in cycles as short as 2 microseconds. The high energy of these pulses ensures complete curing, while their speed enables the lamp to be used with robotic equipment in high-speed production lines. Temperatures at curing surfaces can be kept as low as 100degF.

In addition to reducing the number of UV lamps required to cure irregularly shaped objects such as gaskets, the new Xenon pulsed- UV lamps reduce the need for photoinitiators because of the broad- band spectral output of the new lamp at high peak power. The lamps are used to seal Boston Scientific balloon catheters as well as Digital Equipment and IBM computer hard drives.

European aluminum-casting companies are achieving greater control over the pouring of molten aluminum into vertical castings by using the LaserPour aluminum-slab-mold level-control system, developed by Selcom Inc. in Southfield, Mich. The system improves the surface quality and uniformity of aluminum castings, and reduces the scrap rate by preventing too much or too little molten metal from being poured.

The control system uses several Selcom SLS-5000 laser measuring probes to emit pulsed-laser-light beams reflected from the surface of the molten aluminum. Processors built into each probe head send these measurements to a system controller connected to industrial programmable logic controllers and modules that will adjust how molten aluminum is poured to match preset parameters. Selcom engineers developed a dynamic laser feedback loop to allow accurate measurement without regard to color, ambient light changes, variations in object-reflectivity speed, material temperature, or general environmental conditions.

Each laser probe is enclosed in an air-cooled jacket to protect it from the high temperatures in the casting area. The probe is also equipped with an air purge system that protects the probe lens. A remote console enables the system operator to select pouring parameters by means of potentiometers and selector controls. Among the end users of the Selcom LaserPour system are Commonwealth Aluminum of Australia; Eurofoilin in Dudelange, Luxembourg; Alcoa in North Harrow, England; VAW in Berlin; and Elkem in Mosjoen, Norway.

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