Powering up

18 June 2012


With demand for electricity booming, crane manufacturers are finding work across the power generation sector, from building wind turbine components to lifting fuel assemblies in nuclear power plants. Nicole Robinson reports

Federal energy use standards have been enacted for every major appliance for the home. However, over the past 30 years, electricity used by appliances and electronics in our homes has nearly doubled, according to the U.S. Energy Information Administration (EIA). New home sizes have increased steadily since the 1970s, adding to demand.

Of course the same agency says energy use per capita continues to decline because of the recession and improvements in energy efficiency, but no matter how the numbers are crunched, there will always be a demand for power. The EIA reports that, in 2010, energy produced in the U.S. provided about 75% of the nation's energy needs, with the remainder supplied mainly by imports of petroleum. While the debate will forever rage over the best way to supply energy - coal, nuclear or renewable and alternative sources - and with a majority of it being produced locally, the crane industry stands in good stead to siphon off business. "The power industry is still an evolving industry with new technologies," says Scott Lane, a branch manager with Konecranes. Cranes are utilized in every facet of power generation. Nuclear, hydro, coal, solar and wind all utilize cranes and hoists in one manner or another. As long as the laws of gravity hold true, cranes will be helping power generation companies."

Speaking with Bernd Forwick, product manager for cranes and crane components at Demag, he identifies two markets for cranes in the power generation industry: power generation facilities, such as plants and wind farms, and power generation equipment manufacturers' facilities.

When it comes to power generation, cranes are most commonly used to maintain equipment. For example, at a hydro-power plant - where water drives turbines, which drive generators - these turbines and generators need to be maintained and rebuilt on a periodic basis, and cranes are required to accomplish these tasks.

"You will find cranes in those facilities that typically have fairly high lifting capacities, but are not designed for high duty cycles because typically the maintenance happens infrequently," he explains. "These cranes really spend a significant amount of time just sitting there before being activated to lift a very heavy and expensive component.

"Obviously this market has a great variety of cranes - some of them are very, very old but they are still fully functional. For instance, in the power generation facilities of Hoover Dam, there are bridge cranes that go back to the '30s when Hoover Dam was built. They are still there and they are still fully functional, after periodic upgrades."

At the manufacturing level, cranes are used in the different power generation industries, particularly for gas or steam turbines. Demag has noticed an increase in demand in the last five years for new installations that build gas turbines. Natural gas has created many of these opportunities.

"Improved processes are now available to extract more natural gas out of dense shale rock, which is prevalent in the U.S.," says Martin Marincic, product manager for process cranes at Demag. "This has increased demand for gas turbines as well as cranes used to manufacture them."

Part of this work has also included expansion and upgrade work at existing plants to handle larger and more sophisticated turbines. "Those plants need a great number of cranes with a great variety of lifting capacities and specific functionality," Forwick explains. "Many of these cranes are handling high-level process equipment that needs to be handled very carefully. Steam turbines and gas turbines run at very high temperatures and at very high speeds. Anything that turns in the turbines needs to be very balanced, needs to be assembled and built to very precise tolerances. This requires cranes that allow the manufacturers to assemble the turbines with great accuracy at high capacities." He adds that the finished weight of a gas turbine can be between 300t to 400t, requiring another crane or cranes to move the turbine to a rail car or other special transport to the power plant.

Industrial Training International (ITI) provides overhead crane operation and inspection training. The organization and its trainers work all over the U.S. and internationally, and across many different industries. Zack Parnell, vice president of operations at ITI, says these types of courses at the fundamental level are competitive, especially when offered regionally, reducing the customer's cost when a trainee doesn't need to travel. Instead ITI focuses on offering advanced courses, such as critical lift planning.

Companies involved in raw material extraction and power generation are more able to invest in training opportunities, particularly advanced courses. "Definitely oil and gas, mining, nuclear," says Parnell. "It's not only extraction, but energy. That is certainly the industry group that, to put it bluntly, has the resources to pay for training and they are typically handling very expensive products. Whether you're mining oil or gold or pot ash, that product is so valuable."

Coal
In 2011, 42% of the electricity generated in the U.S. came from coal, and coal plants are continuing to be built. Coal power requires turbine cranes ranging from 50t up to more then 250t depending on the size of the turbine.

"However, a large amount of the cost of crane ownership goes into the 100-plus support cranes that operate throughout the coal plant," Says Konecranes' Lane. "These could be for the river intakes, pulverizers, coal belts and maintenance shops, among other applications."

While coal, a fossil fuel, may often receive criticism it is very much evolving. New plants are being built and new technology has reduced emissions. For example a new integrated gasification combined cycle (IGCC) coal plant being built by Duke energy will create "six times the amount of electricity and less emissions than a similar plant built in 1940." Lane explains, "it's a coal power plant without any stacks. There is little or no emission going into the atmosphere."

Nuclear
According to the EIA, nuclear power provided slightly more than 19% of the U.S. electricity in 2011, and the U.S. is the leading nation for nuclear generation.

PaR Nuclear, a subsidiary of Westinghouse, designs, manufactures and services fuel handling equipment and outage critical cranes for the nuclear power industry. Located in Minnesota it services two markets: new plants and upgrading used equipment at current sites.

For nuclear power plants there are the very large polar cranes in the containment (the big dome structure) portion of the facility. Polar cranes ride on circular rails and are typically used to lift very heavy, safety-related equipment, explains Sara Mancell, responsible marketing and strategic growth at Westinghouse.

"Primarily what a polar crane is used for is lifting off the head of the reactor. When they go into what they call an outage - when they shut the plant down - they need to go in and move the fuel assemblies that are in the reactor."

This type of maintenance is undertaken every 18 months to two years and can last for several weeks or months. The polar crane will then sit idle until the next outage.

Secondly there is the cask crane, of which the primary function is to help move and load the big concrete casks that store spent fuel rods. Mancell explains that a dry cask campaign, when a plant decides to load and seal dry casks, typically occurs in conjunction with an outage.

"The site actually has to have a license from the NRC [Nuclear Regulatory Commission]," she says. "Not only do they have to be licensed to operate the plant but they have to be licensed and authorized to store those dry casks on site. Typically they are licensed for a specific number of casks and they may fill just a couple during the course of an outage, and then close everything up. They'll operate for another 18 months, and then when they go back and refuel, then again they'll load up a few more casks."

Like the polar cranes, the cask cranes only see action during the outage, every year-and-a-half to two years. This is a challenge because the cranes see heavy use in a short period with long down time, and a down crane during an outage destroys a very critical schedule.

A fully automatic high speed/high capacity waste to energy crane with high volume orange peel type grabs, from Demag
Source: U.S. Energy Information Administration, Electric Power Monthly, (March 2012). Percentages based on Table 1.1, preliminary 2011 data.