Sizeable problem solved for French nuclear power plant
A challenging problem with a distorted flange on a reactor access hatch at an EDF nuclear power plant in France has been successfully solved by Furmanite, the speciality services company geared to maximising asset uptime. Furmanite used a purpose-developed machine – on a scale unprecedented in Europe – to allow the issue to be addressed in-situ, demonstrating an exceptional capability and resulting time and cost savings.
The sheer physical scale was at the root of the challenge. The materials access hatch flange on the reactor at EDF’s Chooz power station had become distorted over years of service, primarily because of subsidence of the concrete internal enclosure, and flange face machining was required to restore the flatness. Given the hatch’s colossal weight of over 70 t and an 8 m internal diameter, an in-situ repair solution was clearly the preferred option but the scale exceeded the on-site machining capabilities available. Moreover, accuracy of the finish to within high level tolerances was required, adding to the challenge.
Measures had to be applied to undertake the work in a nuclear environment, including specific training for the technicians, monitoring of radiation exposure, and special measures for decontamination of tools
Furmanite, known for its specialist on-site machining expertise and its extensive experience in the nuclear power industry, was called in to help. In discussion with the plant operator, a plan was conceived to construct the largest diameter milling and turning machine in Europe to enable the necessary remedial work to be undertaken in-situ, within the high precision tolerances required.
“The Furmanite 4000-8500 modular orbital facing machine not only extends the boundaries of high tolerance on-site machining, but also exceeds the capabilities of respected traditional high-quality engineering workshops,” Furmanite European managing director Tony Nicholls points out. “Designed for both single point turning and milling operations it can handle work faces up to a huge 8.5 m diameter and can be used in a horizontal or vertical plane.”
With the modular orbital facing machine designed, built, and on site, the internal hatch cover was removed so that the collar face, which was set in concrete, could be accessed. Up to 16 mm was removed from the face in the most distorted areas and a sealing groove was re-machined in. The mating face on the hatch cover was also machined to ensure a perfect air-tight seal.
The sheer scale of the task was a key challenge for Furmanite
In addition to the scale, the fact that the machining was performed in the vertical plane made it particularly challenging. Measures also had to be applied to undertake the work in a nuclear environment, including specific training for the technicians, monitoring of radiation exposure, and special measures for decontamination of tools.
The exceptional capabilities of the machine include being able to deliver 0.4 mm flatness and 0.1 mm roundness at the maximum diameter (8.5 m), with a surface finish of 3.2 microns Ra under all cutting, milling and turning operations.
“This equipment now has the potential for similar applications across other industries where large scale in-situ flange facing to high tolerances is required,” Nicholls points out. “What’s exciting is the potential we now have to deliver substantial savings in terms of time, cost, and logistical issues both by avoiding the need to remove and transport such large structures to be worked on off-site, and by minimising downtime while the work is carried out in-situ.”
In discussion with the plant operator, a plan was conceived to construct the largest diameter milling and turning machine in Europe to enable the necessary remedial work to be undertaken in-situ
An EDF spokesperson said: “EDF is now working together with Furmanite and the other suppliers involved in this operation on the second part of the contract, which is Chooz B2. Taking into account the feedback and experience gained from Chooz B1, the first and successful operation in 2005, EDF expects to keep to the outage schedule and obtain at least the same level of quality as for Chooz B1 in terms of flatness and roughness of the flanges.”
SCR for Songyu
USA-based Cormetech, Inc. has been awarded a contract to supply the SCR (Selective Catalytic Reduction) catalyst that will be installed in the retrofit De-NOx system provided by SEC-IHI (SEC-IHI Power Generation Environment Protection Engineering Co., Ltd) for the Xiamen Huaxia International Power Development Co., Inc. Songyu power plant. Located in Xiamen, Fujian province, China, the Songyu power plant consists of four coal-fired units producing a total of 1200 MW of electricity for China.
Unit 3 and 4’s SCR catalyst has been installed with the commissioning done in April 2006 while commercial operation of the SCR in units 1 and 2 of Songyu will commence at the end of 2006.
The Songyu contract is a key milestone in Cormetech’s development of business in China as well as Asia in general. The installations of Cormetech catalyst in the De-NOx systems of the Songyu power plant will strengthen Cormetech’s position internationally, continuing the company’s reputation as a leading supplier of SCR catalyst.
A spectacular new ride at Blackpool Pleasure Beach in the UK takes people for a 97 km/h speed spin in three different directions at up to 31 m above the ground. The ride – known as ‘Bling’ – demands considerable amounts of power and the owners of the park looked to ABB to help them deliver the electricity required without having to upgrade the power network.
The Bling ride places a big demand on the three-phase power network serving one of the world’s greatest entertainment parks. The ride was expected to draw around 1400 A per phase. With the installation of ABB’s power factor correction equipment the supply current needed was reduced to 1200 A per phase which, in turn, has meant that the power needed to operate the ride was cut by approximately 25 per cent.
FGD for UK plants
Lentjes GmbH, based in Dàƒ¼sseldorf, Germany, a subsidiary of the GEA Group Aktiengesellschaft has, together with its UK-based affiliate Lurgi UK, won new orders with a total volume of over €300 million. The contracts cover the supply and services to fit flue gas desulphurisation (FGD) plants at the Fiddler’s Ferry and Ferrybridge power stations.
Both stations are owned by Scottish & Southern Energy (SSE), based in Perth, Scotland. SSE is the largest generator of electricity from renewable sources in the UK and is also the second largest generator of electricity in the UK. The installation of such plants will allow SSE an extended operation of these power stations complying after installation of the FGD plants with the European Large Plant Combustion Directive (LPCD).
The Fiddler’s Ferry power station was commissioned in 1971 and consists of 4 x 500 MW coal fired boilers. The limestone/gypsum FGD system incorporates a bypass system and a gas/gas heater for reheating the flue gases to over 80à‚°C prior to being discharged through the existing chimney. The limestone delivery and gypsum off-take will be by rail and modifications to the existing coal delivery circuit are included in the supply, together with a tubular conveying system to transport the limestone/gypsum to and from the absorber area of the FGD plant.
The Ferrybridge power station is one of many located on the Severn Trent river system running through the centre of England known as ‘Megawatt Alley’. The power plant consists of 4 x 500 MW coal fired boilers designed to operate on UK medium sulphur high chlorine coals. In line with the requirements of the LPCD, the FGD plants will be designed to remove 94 per cent of the incoming sulphur load. The supply also includes a bypass system and a gas/gas heater to reheat the gases to 80à‚°C prior to discharge through an existing renovated chimney.
GE Energy has announced that it is to perform compressor tests of its new Evolution compressor in Massa, Italy. The tests will map the aerodynamic characteristics of the compressor and validate the performance improvement.
GE Energy’s new Evolution compressor is the first phase of a multi-phased Evolution programme aimed at future output and heat rate improvements to existing 7B through 7EA and 9E gas turbines. The programme incorporates extensive GE experience in compressor design and a significant number of design practices learned from field lessons. The blades were designed utilizing a 3D aerodynamic design methodology used for GE aircraft engines.
GE has signed a contract to install the first Evolution compressor on a GE Frame 7E gas turbine that has been in operation since 1989 at Midway Sunset Cogeneration’s power plant near Taft, California, USA. The new compressor is expected to improve the heat rate of the gas turbine and increase plant output. Installation at the Midway Sunset site is planned for spring 2007. Additionally, field validation tests will be performed during the installation period.
Industrial WAN/LAN integration
GarrettCom Europe reports that it has strengthened its position as the foremost supplier of networking solutions to the power utility industry by adding key products from the Dymec range to its own portfolio. The Dymec ranges of serial IEDs and wide area networking products complement GarrettCom’s ranges of managed and unmanaged Ethernet switches, and will allow GarrettCom to offer the unique proposition of providing customers with a fully integrated substation network.
The enhanced product portfolio will make it possible for GarrettCom to support the complete communications requirements of a power substation
The enhanced product portfolio will make it possible for GarrettCom to support the complete communications requirements of a power substation, including serial or Ethernet IED connectivity at the sensor and relay levels, high-speed connectivity for surveillance devices, and the WAN router that forwards data and control information for centralised processing.
Yangtze crossing is a towering achievement
Even the Eiffel Tower is dwarfed by a pair of new suspension towers near Shanghai. The 346.5 m-high structures are the tallest of their kind in the world: their sole purpose is to carry power lines over the Yangtze Kiang River. Access for service and maintenance posed unique challenges and the solution has been to install a specially-adapted Alimak SE 400 FC industrial lift in each tower.
This saves crews from having to climb structures that are taller than all but a dozen or so of the world’s highest buildings. The Alimak lifts carry maintenance staff 330 m up to the highest access levels of the towers at a steady speed of 0.8 m/s so the journey takes just seven minutes. The only other way up involves climbing a dizzying spiral staircase, which turns around the lift’s core structure.
The towers stand 2.3 km apart, each occupying a base footprint with a side of 68 m. They have cross arms 72 m wide, carrying the high voltage power lines across the river. It is a major shipping route and the height of the towers was dictated by the need to provide adequate clearance under the power lines.
Alimak had to ensure that the complete lift structure would fit into an area just 1.5 m in diameter, and resulted in a customized solution based on the SE 400 FC lift model
Despite the huge size of the towers, the space available for the lifts was very limited and it has required considerable ingenuity to adapted existing models in the Alimak SE range.
The combination of limited space and enormous height made the installation unique and considerably more difficult than the container cranes, cement industrial plants, marine facilities and steel mills where the SE series is more commonly used.
Alimak had to ensure that the complete lift structure would fit into an area just 1.5 m in diameter. The available space was less than the smallest existing car produced. This resulted in customised lifts based on the Alimak SE 400 FC but manufactured with rounded fronts and doors to save valuable millimetres. The ride to the top is not for the claustrophobic as the overall car dimension is just 715 mm by 910 mm.
These space restrictions meant that the whole stainless steel electrical cabinet had to be placed on the car roof, rather than being integrated into the wall as would normally be the case.
Drax combats pollution
Drax power station, the largest, cleanest and most efficient coal fired power station in the UK, has invested in advanced spray nozzle technology from Bete Fog Nozzle, Inc. The investment provides Drax with an enhanced solution to further reduce sulphur dioxide (SO2) emissions and improve its industry-leading environmental performance.
Being fully committed to managing, monitoring and reducing the environmental impacts caused by its business, Drax already utilizes Bete TH spray nozzles within its flue gas desulphurization (FGD) plant, specifically to reduce SO2 emissions. The nozzles transform bulk limestone slurry into droplets and bring these droplets into contact with the flue gas providing sufficient surface area to achieve the required SO2 removal.
However, while Drax is already the UK’s leading power station industry for minimizing environmental impact, the company constantly strives to improve its environmental performance, therefore the decision was made to assess increased measures to lower emissions. After a full evaluation of the alternatives, Bete DTH absorber spray nozzles were recognized as the perfect solution.
After a full evaluation of the alternatives, Bete DTH absorber spray nozzles were recognized as the perfect solution for Drax power station in the UK
The TH nozzles that Drax had been using previously delivered only a single direction spray. DTH nozzles incorporate two hollow cone spray patterns, one spraying up and one down. The dual direction spray can reduce the installation cost by using less piping layers to cover the scrubber. As a result, the spray nozzle reduces the pressure drop across the absorber and increases average droplet residence time, thereby increasing the efficiency of the SO2 removal process. The geometry of the DTH’s design also produces the most uniform spray distribution possible in each cone.
Initially, Drax incorporated two rings of DTH nozzles in one of its six FGD absorber towers with outstanding results. Due to this success, the company has already placed an order to introduce DTH spray nozzles in another of its towers and, ultimately, all six towers will benefit from the advanced sprayer solution.
According to Les Lemmon, engineering and maintenance team leader at Drax power station, the system has proved a resounding success, “Bete has delivered exactly what it promised, a highly efficient solution performing to our precise specifications.” He continued, “Coupled with a first-class product, Bete has also provided unsurpassed levels of support, accessibility and reliability. We look forward to completing the installation in all our FGD absorber towers.”
Real time control
Luxtron, leading provider of fiber optic temperature measurement solutions to the power utility, industrial and medical industries, announces the release of its ThermAsset2 temperature controller, designed for cost effective, direct, real time control for power transformers down to 25 MVA.
The ThermAsset2 is a sought after addition to the Luxtron product line, offering a primary controller to monitor hot spots, control cooling, and protection at a cost that is attractive to apparatus engineers and system operators. Available in 2 or 4 channel configurations, the ThermAssets offer full control with alarm status indicators for up to six customer-specific relay functions.
This controller offers many of the reliable and proven features found on Luxtron’s WTS-22 and ThermAsset systems, considered the standard for fibre optic temperature measurement of transformer windings in the power utility industry.
Power quality performance
Dranetz-BMI, a worldwide leader in power monitoring instrumentation, has introduced the PowerGuide 4400, the only advanced monitoring instrument to incorporate a colour touch screen into its lightweight design.
Users of the Dranetz-BMI PowerGuide 4400 can select the length and mode of data collection
With the PowerGuide 4400, users can select the length and mode of data collection, including troubleshooting, data logging, fault recording, inrush, power quality surveys, equipment performance testing, energy studies, and loading balance. Automated setups provide instant detection of circuit types and configurations, ensuring that the instrument is ready to successfully collect data. The PowerGuide collects data at 256 samples/cycle/channel for both voltage and current and offers remote communications using the RS-232, Ethernet or USB options.
Standard features with the PowerGuide 4400 include the unique annunciator “report card,” which provides instant power quality answers in the field by collecting and color-coding categories to quickly identify areas of concern.
High performance in extreme environments
WahlcoMetroflex, a worldwide leader in the design and manufacture of dampers, expansion joints and systems for isolating and controlling gas flows, offers high-performance metallic bellows. These expansion joints are engineered and manufactured to operate under very extreme temperatures and pressure conditions at utilities, smelters, steel mills, refineries, petrochemical plants, chemical plants, cement plants, pulp and paper mills, waste heat recovery and cogeneration facilities.
The expansion joints are engineered and manufactured to operate under very extreme temperatures and pressure conditions
With more than three decades of experience manufacturing metal bellows for the world’s most demanding applications, WahlcoMetroflex engineers design the most appropriate and economical expansion joint style and material for each installation. Styles include axial single or double bellow sets, with or without anchor bases; universal single or double tied units, with two or more tie rods; articulated single or double hinged and single or double gimbal; pressure-balance bellows in in-line, elbow and tee configurations; and applied-pressure internal or external to bellows.