The Courier 10 consists of two components: the measuring assembly head and the electronics unit. Samples enter the flow cell within the measuring assembly head; different flow cells are available to handle a wide variety of samples, from powders to liquids and slurries.

An X-ray tube or radioisotope in the analyzer focuses X-rays on the sample. The sample then emits X-rays whose energy corresponds to specific components, such as sulfur and ash. The number of measured X-rays correlates to the concentration of various substances in the sample. A proportional counter detects the emissions through a window in the flow cell and generates signals sent via cable to the electronics unit. The unit contains computer boards to process the analytical information and transmit it to the user.

The instrument, now used in Europe, is just being introduced to the North American market.

Woodward's DCS is designed to prevent a single point of failure, such as an input/output module or a duplicated sensor, from causing an entire steam turbine to shut down. It uses three active central processing units that vote on all processed information on a two-out-of-three basis.

Redundant I/O signal paths extend the fault tolerance of the controls out to the critical field devices, such as speed and pressure sensors. In addition, the DCS automatically detects and identifies failed modules and sensors so that they can be replaced rapidly, without shutting down the turbine.

California Energy Co. retrofitted two steam turbines at its Vulcan power plant, 100 miles east of San Diego, with DCSs last year. A voltage surge on a major transmission line running through the nearby Imperial Valley recently tripped every power plant in the region off the grid. The new control at Vulcan automatically tripped the high-pressure steam turbine and operated the low- pressure steam turbine in island mode. The 509 DCS took over frequency control without overspeeding the turbine nor having to shed any of the plant's parasitic loads.

Japanese petrochemical processor Mitsui Sekka recently replaced hydromechanical controls on a single extraction steam turbine with the DCS and Woodward's field-proven TM-25LP dual-coil actuator to enhance stability. The turbine drives a compressor used in ethylene processing at Mitsui Sekka's huge Chiba Works in Keiyo, Japan. Preventing a single unplanned stoppage could save up to $1 million a day.

PocketWelder measures 4 by 7 by 1 inch, weighs 1 pound, and is powered by a 9-volt battery. Several microprocessors within the PocketWelder contain industry-standard programs written by welding engineer Ed Craig. Users press a series of buttons to enter the parameters for a specific welding job, including the type of steel being welded (such as ASTM 514), the shape of the material being welded (i.e., plate or pipe), and the specific type of wire filler needed (for example, ER80S-D2 MIG wire).

The operator then enters the length and width of the weld, and a calculator determines the quantity of wire filler needed. The PocketWelder can also be used to determine the amount of time needed to perform the weld, based on known deposition rates.

In addition, the device can also determine the amount of oxygen fuel needed for a specific welding job as well as the optimum wire feed and voltage settings for spatter-free production. The PocketWelder can help simplify cost and time estimates, and interpret international welding standards. Weldcomp recently introduced a software version of the PocketWelder that replicates the device's capabilities on a personal computer.

The Steeltest 1000 was originally developed as part of a research project conducted for the Electric Power Research Institute in Palo Alto, Calif. The unit consists of a probe connected to the 18-pound electronic assembly. The inspector inserts the probe into the heat- exchanger tube, in which permanent neodymium-iron-boron magnets in the probe set up a powerful magnetic field. Any flaws in the wall thickness will cause distortions to the magnetic field.

Two sensors in the probe head detect those flaws. One is a coil that uses Faraday's law to spot sharp defects, such as cracks or pitting; the other, a semiconductor chip, uses the Hall effect to measure gradual changes in wall thickness. Together, the sensors can detect changes in wall thickness of less than 20 percent, which is long before they would cause a leak.

A rechargeable 24-volt battery powers the Steeltest 1000, which has a four-channel recorder to permanently store and print out test data. A rugged steel casing and extra O-rings protect the inside of the unit from moisture, enabling it to be used in deserts and jungles. Aramco, for example, uses the Steeltest 1000 to inspect heat-exchanger tubes in its Saudi Arabian refineries.

Chemical and petrochemical processors such as Du Pont and Exxon perform inspections with the device to prevent leaks from their process heat exchangers, and New England Electric uses it to inspect the tubing in its power plants. When preventing the processing leak of hazardous materials like chlorine, the Steeltest 1000 offers both environmental and safety benefits.

The CB 20 II is equipped with a turret holding up to 21 tools that punch holes in metal sheets placed on the worktable. Operators adjust the tool stroke by using Behrens's hydroelectronic press drive. The presses are designed to process full 4- by 81/4-inch metal sheets, and their blade clearance can be programmed to match sheet thickness. A single-pallet load system can be attached for simple unmanned applications, while a double-pallet load system is also available when automatic retrieval and storage of finished parts is required.

John Deere Harvester Works in East Moline, Ill., recently installed two combination punch shears, each consisting of a CB 20 II turret press with right-angle shears (made by Karl Eugen Fischer GmbH Machinen Fabrik, based in Burgkunstadt, Germany), to facilitate the punching, cutting, separating, and sorting of finished blanks for its agricultural equipment. Each combination punch/shear machine creates finished blanks in a single routed operation, compared with other machining processes that require a minimum of three routed operations.

"Consolidating those operations into one routed operation yields a tremendous improvement in simplicity and in material flow on the floor," said Gerald Vande Voorde, advanced engineering analyst at John Deere.

The new analyzer is equipped with an in situ sample cell. Near- infrared light is passed through the sample cell and transported to the analyzer via fiber optics. Acousto-Optic Tunable Filter technology combines sound waves and electrical energy to diffract discrete infrared wavelengths. The diffracted light is focused on a detector to measure the presence and quantity of different constituents in the process sample. Each constituent's concentration is provided via a separate 4- to 20-milliampere analog output.

An important consideration for pharmaceutical processors was the design of an external module that checks the optical system to ensure its integrity. The fiber optics themselves are intrinsically safe, so the analyzer can be placed in a general-purpose area. In addition, the analyzer is insensitive to ambient temperature changes and is equipped with self-diagnostics to alert operators if service is required or conditions are out of limit.

The AOTF-NIR analyzer is being tested at Eli Lilly's pharmaceutical research center in Indianapolis. The device has provided real-time determination of hydrogen peroxide and moisture levels within a production isolation barrier designed by Eli Lilly, ensuring properly maintained sterility parameters over the course of the process cycle. The next step in developing the analyzer involves automating the introduction of hydrogen peroxide during sterilization, using closed-loop control.

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© 1996 by The American Society of Mechanical Engineers