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Industry Headlines

Offshore Production Nearly 30% of Global Crude Oil Output

Wednesday, 26 October 2016  |  Chris Guy

Global offshore oil production (including lease condensate and hydrocarbon gas liquids) in 2015 was at the highest level since 2010, and accounted for...



Industry Headlines

Honeywell and Flowserve Collaborate on IIoT Solutions


Honeywell and Flowserve will collaborate to provide Industrial Internet of Things (IIoT) for industrial customers. The collaboration will be part of the Honeywell INspire program, Honeywell's joint customer development program for its IIoT ecosystem.

Honeywell and Flowserve have a long history of colla...


Train Named Executive President of Emerson Automation Solutions


Emerson recently named new senior leadership appointments to its Office of the Chief Executive who now report directly to chairman and CEO David N. Farr, and help develop and guide the company’s global strategies.

Michael H. Train’s new title is executive president of Emerson Automation Sol...


Offshore Production Nearly 30% of Global Crude Oil Output


Global offshore oil production (including lease condensate and hydrocarbon gas liquids) in 2015 was at the highest level since 2010, and accounted for nearly 30% of total global oil production. Offshore oil production increased in both 2014 and 2015, reversing consecutive annual declines from 2010 t...


New 2017 Construction Starts Increasing 5% to $713 Billion


The 2017 Dodge Construction Outlook predicts that total U.S. construction starts for 2017 will advance 5% to $713 billion, following gains of 11% in 2015 and an estimated 1% in 2016.

Manufacturing plant construction will increase 6%, beginning to recover after steep declines in 2015 and 2016 that refle...


Richmond Fed: Manufacturing Rises But Remains Sluggish


Manufacturing activity fifth district (MD, DC, VA, WV, NC, SC) remained sluggish in October, according to the most recent survey by the Federal Reserve Bank of Richmond. New orders and backlogs decreased this month, while shipments flattened. Hiring activity strengthened mildly across firms and wage i...


Consumer Confidence Retreated in October


The Conference Board Consumer Confidence Index, which had increased in September, declined in October. The index now stands at 98.6, down from 103.5 in September. The present situation index decreased from 127.9 to 120.6, while the expectations index declined from 87.2 last month to 83.9.



Actuation in Nuclear Power Plants


The thousands of actuators used in a nuclear plant face some pretty tough conditions as well as rigorous testing.

Currently, 104 nuclear power-plant reactors are working in the United States, and all of them have operating environments that are extremely challenging. Of those 104 plants, 35 are classified as boiling and 69 as pressurized water reactors.

While the design details vary from plant to plant, each nuclear facility has thousands of valve actuators used in various processes and applications. The newest-generation nuclear plant has more than 13,000 valves.

It’s clear, then, that valve actuators play vital roles in maintaining process safety, efficiency and productivity in a wide range of situations.

This article contains a brief description of some of the special circumstances encountered in challenging nuclear environments and the different styles of actuators used to meet demanding operational and safety requirements.


vmfall11_nuclear_electric_actuatorWith O-ring sealed covers in place on this electric actuator, the motor, limit and torque switches, as well as other electrical components, are housed within a pressure-tight enclosure. This keeps out dirt and moisture and prevents breathing from expansion and contraction of the internal air caused by temperature changes.All equipment used in nuclear plants built in the United States is certified under stringent guidelines mandated by the Nuclear Regulatory Commission (NRC). Verification of reactors or equipment to standards from other countries is not acceptable for the 104 working reactors in the U.S.

To understand basic requirements the nuclear power industry faces in this nation, a review of the similarities and differences between nuclear power and fossil power is helpful.

In a fossil power plant, coal might be crushed and mixed with air to boil water, which produces steam to drive a turbine. With nuclear reactions, the process is different, but the operational objective is essentially the same—to heat water to produce steam to drive a turbine. With a coal steam generator, the activity of burning the pulverized coal and producing steam is contained within what is termed the “boiler island.” Because of the strong similarity to what happens in the coal plant, many engineers and technicians in a nuclear plant refer to the area where steam generation occurs as the “nuclear island.”

vmfall11_nuclear_cutawayThis cutaway illustration shows the internal components of a typical electric actuator.Within the nuclear reactor, equipment must meet rigorous standards. Since radiation is very high, the standards require all equipment materials used in this phase of the process to withstand high levels of radiation for the life of the plant. Therefore, materials such as iron or steel are required rather than aluminum. Also, temperatures in this portion of the plant are elevated, which will affect seal materials. The combination of severe environmental conditions determines the various coatings and paints allowed for use in this area, which is known as “inside containment.”

To be suitable for service in a nuclear reactor, an actuator must go through specific testing by outside testing agencies. The test reports produced must then be reviewed not only by the actuator suppliers, but by consulting engineers and the utilities themselves. Many documents also are reviewed by the NRC.

The tests for actuators used “inside containment” apply to all styles. The plants use electric motor operators as well as pneumatic cylinder actuators and hydraulic cylinder actuators. All of these actuators must be tested to ensure they can withstand the environment for their expected lives. Also, in addition to environmental concerns, the actuators must be able to operate during extreme accident conditions such as an earthquake.

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