TPi April 2010

developments products &

Bespoke mobile access system

a safe means of evacuation in the event of emergency.

Harsco Infrastructure’s design employs powered, self-propelled work platforms suspended from a steel framework. The entire rig travels along the pipes on a series of wheels, which are specially angled to accommodate the cylindrical surface of the pipes. Users of the system gain access to the work platform via a cradle suspended from an electric hoist attached to the frame. One challenging task for Harsco Infrastructure was to find a way for the system to traverse the steel flanges which project around the circumference of the pipe sections. This was solved by providing a jacking system that lifts the wheels clear of the flanges as they pass. The inaccessible location of the site required the use of a high-capacity mobile telescopic crane to lift the two access rigs into position on top of the ACC pipes. Peterborough Power Station, which entered into operation in 1993, uses ‘grey’ water supplied by the local sewage works to generate steam for its turbines, thereby reducing the consumption of expensive potable water. The condenser is air-cooled rather than water-cooled, to further reduce water consumption.

enormous horizontal steam pipes with obscure angles that made the ACC units inaccessible by conventional means. Also, with the pipes reaching a surface temperature of 65ºC, the access system has to withstand high temperatures and still be functional. East Coast Industries awarded Harsco Infrastructure with the contract to design, manufacture and install a mobile access system that would allow safe access to and from the working area. The system was also required to provide

Access and scaffolding contractor Harsco Infrastructure has designed and installed two bespoke mobile access systems to allow contractors to carry out essential maintenance work at Peterborough Power Station. Centrica, which operates the 360MW gas-fired power plant, has enlisted industrial painting specialist East Coast Industries to carry out the work, which involves cleaning and re-painting the air-cooled condenser (ACC) units. This has involved working on the ACC’s

Steel wire reinforced thermoplastic composite pipe The new SRTP pipe from ESRTP/Yesaint is a steel wire reinforced thermoplastic (PE) composite pipe, which is also an HDPE pipe upgrade. Among metal pipes, steel pipes are cheap in price and hard in strength, and have always taken a lead in the market. However, they are prone to erosion and corrosion, and may bring pollution to the fluid media and environment. In addition, as the price of metal materials grows, the cost of metal pipes rises. Non-metal pipes, most of which are of plastic, are taking the place of metal pipes in some areas. However, though they have solved the problem of anti- corrosion and pollution, they are rigid in adapting to temperature, and are easily cracked. They cannot resist high temperature and pressure, which limits their wide use. SRTP pipes make up for the lack of anti-corrosion ability of metal pipes and the lack of pressure-resistance of plastic pipes. By the special electric melting and connecting method, the pipes can also ensure stability during the process of installation. The SRTP pipe uses highly intensive spiral steel wires as reinforcement, and HDPE as the base. It also uses bonding resin to combine the steel wires and the base together. The pipe is structured with inner plastic, special heat melting glue, twining steel nets and outer plastic. The pipelines are manufactured using electric-melting welding and flanged connection. Product features include long service life: under standard condition it can be safely used for a minimum of fifty years. The inner wall is smooth, with small transmission resistance. According to Yesaint, compared to the water transmission rate of steel pipe of the same inner diameter, the flow rate can be raised by 30%. The company also claims the pipe has wear resistance of four times that of steel pipe. The pipe is also tough, and light in weight. Yesaint’s production line is able to provide 13 specifications of SRTP pipes, from DN110 to DN630. The pipe is especially suitable for gas and water supply, as well as other applications that demand high pressure and corrosion resistance.

Harsco Infrastructure – UK info_infrastructure@harsco.com www.harsco-i.co.uk

ESRTP/Yesaint – China info@yesaint.com • www.esrtp.com

The access rigs being lifted into position on top of the ACC pipes

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Tube Products International April 2010

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