In the beginning
The nuclear industry has its roots in the work of scientists like Ernest Rutherford and Enrico Fermi who, at the beginning of the 20th century, conducted pioneering experiments on nuclear reactions. The first reactor, Chicago Pile-1, was built by Fermi in 1942 in a racket ball court at Chicago University, as part of the wartime Manhattan Project. After the end of World War II, the US and USSR gradually turned their attention to the use of nuclear science for peaceful purposes.
The International Atomic Energy Agency was set up in 1957 to promote the peaceful use of nuclear technology. Through the 1960s and 1970s the potential of nuclear power as a source of energy was developed by countries around the world. The development of the Oyster Creek plant in New Jersey, completed in 1969, pioneered the design and construction of nuclear plants as turnkey projects.
As nuclear power plant construction took off in the US in the 1970s, one company, Lampson International, played a crucial role. Bryan Pepin- Donat, director, contracts and international business, says: “Neil Lampson provided the design basis and built the first Transi-Lift in 1978. The specific intention of its design was that it would be used to pioneer the overthe- top method of installing nuclear components including steam generators, reactor pressure vessels, polar cranes, aux generators, turbines and the reactor building dome complete with all of its utilities.
“The over-the-top method, devised by Neil Lampson, allowed for considerable time savings and eliminated site interdiction with respect to other activities. It also allowed for considerable work to be accomplished at grade level that previously had to be done at elevation. For instance, reactor building top closures (domes) had been built by flying the materials to elevation using cranes, then the welders had to be transported up and the welding done in place. By allowing this work to be done at grade the labour costs were reduced by some 30% and the completed top closure could be set on a weekend in a single day.
“The dome for WPPSS Hanford 2 [in Washington State] was built about 100m from containment at grade. Using the Transi-Lift we were able to come in on a Saturday, pick it up, walked it 100m, and set it in place in about five hours, without interdicting other work.
“The old method was to use a service hatch in the side of the containment. This required the polar crane to be stick built at elevation in order to set the various components. That method took a lot of time, required further assembly in the containment as well as interdicting work in and around the containment structure.”
Nuclear power construction was being developed around the world. “China’s nuclear industry began in 1955,” says William Chen, the director of Zoomlion’s overseas market after service department. “In 1985 China began to build the first nuclear power plant on the Mainland, the Qinshan Nuclear Power Plant, and put it into operation in 1994. As to January 2009, China’s mainland has 11 nuclear power generating units in operation with a total installed capacity of 9.12GW. Currently, 35 sets of nuclear power unit are under construction, with a total installed capacity of 37.28GW.”
Lampson wasn’t alone in recognizing the special demands of the nuclear power sector. Terex Cranes senior manager, product marketing, Rüdiger Zollondz says: “In 1982, we delivered the CC12000, which was made to lift 1,000t out to 48m, in order to lift the dome of a new plant. Unfortunately, between the crane being delivered and the job starting, Chernobyl happened [on 21 April, 1986], and construction of the plant was stopped.”
A few years before Chernobyl, on 28 March, 1979, the US had experienced the worst reactor accident in its history, at Three Mile Island in Pennsylvania. Despite scientists later finding that there was no identifiable increase in cancer deaths, the release of radioactive gases from the plant provoked public panic.
At the same time, none of the US nuclear manufacturers who had built turnkey plants managed to generate a profit. According to the IAEA, two in every three plants commissioned around the world after 1970 were subsequently cancelled.
After the meltdown
With the meltdown of new plant construction at the beginning of the 1980s, lifting companies turned their attention to the decommissioning and maintenance of existing plants. “Subsequent nuclear work consisted of steam generator removal and replacement,” says Pepin-Donat. “In this process, the steam generator is removed through the top of the containment, placed on transport and moved to storage. The new steam generator is then transported into the plant and lifted into place.”
Javier Martinez, executive director, ALE Heavylift, says: “Many plants changed their old steam generators in recent years, because of problems with materials. New steam generators were able to offer more steam even above the nominal figures, so nuclear plants now have the chance of installing new electrical generators which can turn the extra steam available into more electrical power.
“Other jobs are being done because many reactors were built in the late 1970s. Now, after 30 years, many components have reached the end of their life cycle. The reactor head, for example, often needs to be exchanged to extend the life of the plant. Sometimes, the quality of materials used 30 years ago does not match the quality available today.”
The problem is power plants weren’t built for this sort of job, Martinez says. “At the design stage on these plants, it was never assumed that most of these parts, reactor heads, steam generators, condensers, heaters, electrical generators and others, would ever need to be replaced. The building and hatch openings were not designed to allow all these elements to be removed. Often the only way to remove them is to cut the containment open. Reactor containments were designed to withstand a direct missile strike or jumbo jet crash. Walls are up to 2m thick and use bars of 72mm.”
Pepin-Donat explains how the generators are removed, in decommissioning jobs: “Decommissioning projects in which the internals such as the steam generators and the reactor pressure vessel were removed through the top provided additional opportunities. We worked on the decommissioning of San Onofre, in California. The steam generators, pressuriser and the reactor pressure vessel, and other components were removed by lifting them out through the roof. That saved a considerable amount of work compared to removal through the service hatch.”
“Every day a plant of 1,000MW is out of operation, a million Euros of generating power may be being lost,” says Martinez. “It’s a difficult environment, with poor working conditions. You can’t allow any dust or humidity because of the risk of contamination. These buildings weren’t designed for the job, and we need to work in shifts 24 hours a day, up to 70 days at a time, dressed in specific clothes, usually in high temperatures. The difficulty on refits isn’t the weight of the load, it’s the building design and the limitations of the job site.
“We are working on the change out and replacement of electrical generators at two sites: at Almaraz in Spain, and at Krško in Slovenia. We are exchanging 475USt electrical generators at Krško, using SPMTs and a tailormade gantry: it is a refit, in a closed building, with no space for cranes.
“The project at Almaraz is the same: we take out the old generators from the turbine building by the equipment hatch and install new ones without modifying the building.
“We use a custom frame and trailers to exchange the reactor head. The reactor head vessels were designed to always be vertical, not to be moved in a horizontal position. We needed to design a frame to allow them to be tilted. The reactor head may only weigh between 50t and 90t, but it is the heart of the nuclear plant. Each reactor head may cost up to €20m and take more than a year to produce it.”
Terex has also looked to nuclear plant refurbishment and decommissioning. “For refurbishment jobs, all of our cranes are used, but especially larger ones,” says Zollondz. “They’re used for replacing components, both on nuclear plants and conventional power plants.
“The problem is, in these jobs, the building itself is an obstacle, so you need to be able to reach over. For refurbishment, you are lifting smaller loads, maybe only 100–250t, but further. For modular construction, the loads are much heavier.
“On refurbishment jobs, our large crawler cranes are typically used with superlift and luffing jib, because you need the reach. For crawlers, they are working in SWSL configuration. We saw a customer buy two CC8800s for plant refurbishment jobs. We’ve seen plans to use a 1,250t crawler to replace a steam turbine, by putting the boom partly into the building. The CC9800 might be an excellent model for refurbishment jobs, as it reaches higher and further into the building than previous models.
On these jobs, it is not just installing the generators and other components that is an issue, but getting them to the plant. Edoardo Ascione, president of the US arm of Italian-owned Fagioli, says: “In the last six or seven years, Fagioli has moved more than 40 replacement steam generators, weighing 250–800t, for around 12 projects. We’ve also moved reactor vessel closure heads, weighing 60–150t. We’ve moved all of these components on a door-to-door basis, from manufacturers overseas to plants in the US.
“In the US, there are over 100 nuclear power plants, all of which are more than 25 years old. None of this equipment is manufactured in the US. There is one manufacturer each in Japan, Korea and Canada, and three in Europe.
“Typically, on the initial construction of the plant, these components were manufactured on site. New, more stringent quality requirements mean they must now be fully assembled at the manufacturers, and tested first.
“All power plants in the US, other than one in Arizona which pipes water 80 miles from Phoenix, have some water access, for use in cooling the reactor. Most components are going to plants that can be accessed in an almost normal way by barge.
“In Arizona though, at Palo Verde, we delivered six steam generators each weighing over 800t, without water access. The difficulty there was that we had to drive more than 200 miles over public and tailor-made roads, from their landing area in Mexico. We delivered them two at a time, between 2003 and 2007.
“Other notable projects included the complete delivery, in November 2009, of two 500t generators from France to Three Mile Island in Pennsylvania. Our clients like that we are able to deliver door-to-door, handling all of the transport interfaces. Working with nuclear people, they apply the same rules to us as they apply at the plant. We have to look at our plans in detail, and build in multiple levels of contingency.
“The Susquehanna River at Three Mile Island isn’t navigable, so we had to deliver the load to a location 80 miles away that is not even a port. We had to bring in a spud barge to create a temporary dock area, then complete the journey over land, through Maryland and Pennsylvania. We were transporting over roads for three weeks, and had to deal with numerous authorities.
“In Arizona, the challenge was technical; it took five years of my life to plan. On Three Mile Island, the challenge was organisational. We had to take out bonds and sureties worth tens of millions of dollars, and have many meetings and discussions.”
• While decommissioning, refurbishment and refits have kept the heavy lift and special transport industry busy for the last 20 years, renewed political support for nuclear power around the world promises a bright future for manufacturers and users of very heavy crawlers and special lattice boom cranes. In the second part of this series, in May, Cranes Today will look at recent and upcoming jobs in this sector.
