Universal sized clinker crushers
In response to demands from the power generation industry, Pennsylvania Crusher has introduced a range of different sized clinker crushers, enabling easy replacement of virtually any model already in existence. All models – including the new sizes – will reduce clinker (boiler ash) to the requisite top size, which is normally 3.18-3.81 cm x 0 cm.
The new sizes incorporate several advantages, notably a hinged panel door that enables clearance of jams and inspections with no need to remove the unit from its operating position. All sizes have a seal arrangement that overcomes the problem of leakage which is prevalent with some other makes.
The crusher’s grinding roll has a special tooth pattern that delivers greater peak crushing force. This results in more efficient crushing. The roll shell of all Pennsylvania sizes is in the six segments, making them lighter and easier to install. This differs to most other makes where the roll shell is either in five or four segments.
The new sizes can directly replace almost all existing models, including single-and double-roll models, by merely unbolting the old units and bolting in the new models.
CCI China contract
CCI, a leading US-based manufacturer of severe-service valves to the power generation industry, has been awarded a $15m contract to provide eight main-steam valve units by the Jiangsu nuclear Power Corp. and the China Nuclear Energy Industry Corp.
The installation will be to serve the first two 1000 MWe Russian designed NPP91-WWER reactors at the Lianyungang nuclear power plant to be built north of Shanghai. Each of the main-steam valve units is made up of five valves.
SEL launches new protection relay
Schweitzer Engineering Laboratories (SEL), manufacturer of microprocessor-based relays for power system protection, has introduced the SEL-701 motor protection relay. SEL designed the relay to combine comprehensive motor protection with innovative reporting functions.
These reports, which include load profiling, and motor start and trend data, provide the user with an unprecedented view of the protected motor and driven load.
The relay provides all basic motor protection features including short circuit, load loss, load jam, and frequent starting protection as well as unbalance current and phase reversal protection. The SEL-701 also provides a patented motor thermal protection element that accurately tracks the heating effects of overload and unbalance current.
The integrated element calculates an estimate of the motor heat energy, based on the measured currents and motor characteristics. The estimate tracks changing conditions to reliably protect the motor from thermal damage.
Each time the motor starts, the relay stores a 60 s report detailing currents, voltage, and thermal model results.
British Energy signs five-year deal with Cimage
In a recent deal signed with British Energy (BE), Cimage – Sun MicroSystem’s largest business partner – will supply a new document management system, enabling the online storage of the tens of thousands of drawings and documents that by law have to be retained by BE. The agreement follows the success of earlier projects between the two parties.
The majority of BE’s 5000 staff need access to these documents and by storing them online Cimage will enable total safety, flexible access and accuracy to the second.
Cimage is supplying BE with a Configured Document Management System (CDMS) which will mean faster and more efficient approval of licensing to get plants up and running as quickly as possible after routine maintenance. It will allow engineers, consultants and designers to access information on the plants in real-time via the intranet from any PC within the BE organization, ensuring consistency, heightened safety and best practice throughout, with massive financial savings as an added bonus.
BE owns and operates eight of the most modern nuclear power stations in the UK. Each plant needs to comply with a number of licensing conditions, from training and safety requirements to up-to-date instructions on how to maintain a piece of machinery. Any change or physical upgrade must be audited to ensure safety, and the most up-to-date documents must be available to staff and official bodies for reference at all times. George Jenkins, executive director of operations at BE, believes that the CDMS will achieve all expectations in these, and other, areas.
Cooling tower re-packed
Munters Environmental Components Division has successfully completed its first cooling tower re-packing contract. A total of 11 500 m3 of media at national Power’s Drax power station was either replaced or cleaned and repositioned during a routine 12 week boiler outage. The deal was worth £500 000 ($825 000).
Munters employed its specially designed media, PLASdek 330.60, which should provide the cooling tower with improved thermal transfer and low fouling properties. Munters provide various PLASdek media dependent upon the level of contamination in the cooling water and the amount of cooling required.
There are 12 natural draught cooling towers at Drax each 84 m in diameter and 115 m high. Water is drawn from the River Ouse, a tributary of the Humber, screened and pumped into large settling ponds where the majority of silt carried by the water is removed. Over several years fine silt has entered all 12 cooling towers but, due to the type of media employed inside three of the towers, silt has settled inside the media forming large blockages. Munters has re-packed one of these three towers. The silt blockage is less exaggerated in the remaining cooling towers because they are packed with a more open type of media.
Voltage-zero switching solves v-speed trips
The problem of variable-speed (v-speed) motor tripping at a cement works has been solved by the installation of ‘voltage-zero’ for a two-stage 11 kV capacitor bank. The technique is usually applied in high-voltage power networks, but ABB Power T&D Power Quality Division, which diagnosed and solved the problem at the Blue Circle works, believes it has considerable potential in industrial medium-voltage networks.
Blue Circle uses many v-speed motors and uses capacitor banks to ensure that the quality of the power network is not impaired by the reactive nature of the motor loads.
ABB T&D was called upon to carry out a system harmonic study in response to plant downtime caused by motor drives tripping during capacitor switching.
The solution was to supply a replacement two-stage capacitor bank with a tuned filter reactor to reduce fifth-harmonic currents, and utilise a new type of contactor. This has a built-in voltage sensor that switches in the capacitor banks for each phase of the power supply only when the phase voltage is at zero. This ‘voltage-zero’, or ‘point-on-wave’ switching ensures that closing transients are virtually eliminated.
The new 11 kV capacitor bank, which has two switched sections of 2.1 MVAr, is now installed at Blue Circle’s Cauldon Works, and since installation the v-speed motor drives have been working without interruption.
GE wins India contract
GE Harris Energy Control Systems Canada, Inc. has been awarded a contract to supply automation equipment for a major electric utility automation project in Mumbai, India.
The contract is to supply substation automation equipment to Bombay Suburban Electricity Supply (BSES) via GE Harris’ local associate Emco. The $2m project will install automation equipment in 48 BSES substations.
BSES is a Mumbai-based integrated power generation and distribution company distributing power to 384 km2 of suburban Mumbai.
The equipment is based on GE Harris’ Integrated Sub-station Control System (iSCS) which includes a D25 multifunction intelligent electronic device (IED), D20/D200 substation servers, and Powerlink graphical user interfaces.
Largest wind turbine in UK starts operation
Peter Brotherhood Ltd., the UK-based supplier of engineering equipment to the power industries, has produced its first wind turbine, which is currently the largest in operation in the UK.
In conjunction with Renewable Energy Systems (RES), a wind energy development company, a division of Brotherhood undertook the project to design and build the wind turbine.
It is expected that the turbine will provide clean power for around 600 homes while saving an estimated 2300 t of global warming gases. It has a 52 m diameter rotor, and the combined weight of the hub, blades and nacelle is 55 t. The structure sits on top of a 45 m-high tubular tower.
The global wind energy market is estimated to be worth about $1.5bn annually, and with rapid expansion is expected to reach $15bn by 2005. Between 1980 and 1988 Europe has seen its capacity rise from zero to 6303 MW – in 1988 UK generated five per cent of this capacity. The UK’s proportion of European generating capacity is likely to rise. The British government has stated that by 2010 renewable energy should account for ten per cent of generation.