TPi January 2013

products & developments

Increase in stainless steel range DK Jones Ltd has announced that the range of stainless steel components stocked in its new, expanded warehouse has been increased. The range of stainless steel items now being stocked includes branch outlet fittings (Olets) and high pressure forged fittings, barrel and swage nipples, solid bar and a range of seamless stainless steel pipe. Several new machines have been installed for DK Jones’s fully ISO- certified in-house machining facilities.

This major new investment in stock and equipment will enable machining of special Olets and high pressure forged fittings from a large stock of high quality semi finished forgings, bar and pipe, ensuring quick delivery time for many standard and non-standard items. In addition to supplying original manufacturers’ certificates with every item, positive material identification (PMI) is available on all materials before despatch. DK Jones believes that this increased warehouse capacity and newequipment will enable customers worldwide to take advantage of shorter delivery times for a wide range of standard and special items in stainless, alloy, low temperature and carbon steels.

These include several specially designed machines for the profiling of Olets and a fully automatic band saw.

Mr P, the DK Jones penguin, helps with the checking of stainless steel couplings before despatch

DK Jones Ltd – UK sales@dkjones.com www.dkjones.com Power suppliers increase demands for steel grades

boilers; increased material resistance against thermal fatigue; and good heat transfer and low expansion coefficient compared to austenitic steel grades. In 1983, ASTM/ASME approved the T/P91 tubes and since then they have been approved by many national standards. Zeleziarne Podbrezova manufactures seamless tubes and pipes to be used in boiler production, especially in central Europe but also worldwide. Two production plants (in Slovakia and Spain) are served by steel from the company’s own production. The outside diameter range is 12.7 to 139.7mm, in wall thicknesses from 0.89 to 12.5mm. Tubes of up to 21.3mm diameter are produced by the cold drawing process. Zeleziarne Podbrezova as – Slovakia admin@zelpo.sk www.zelpo.sk

offering seamless tubes destined for the critical parameters of above 600°C usage. This is provided by the steel grade P91 and T91 or X10CrMoVNb9-1 and corresponding equivalents. P91 grade is ferrite-martensitic steel (9 per cent chromium, 1 per cent molybdenum), microalloyed with vanadium and niobium, and with controlled content of nitrogen. Tubes made of P91 grade are destined for boiler superheaters, power plant tube heaters, headers and duct pipes for high-temperature applications, and eventually for furnace ductwork in petrochemical assembly. Advantages of P91 grade include improved strength and material creeping behaviour at higher temperatures; improved material corrosion resistance compared to other boiler type grades; decrease of tube weight and subsequently tube components and

Economic pressure is forcing power plant operators to increase their effectiveness by increasing temperature and steam pressure to provide energy at the lowest prices possible. For current power stations, the characteristic steam temperature at the turbine intake is between 540°C to 565°C, although in the last few years, there has been an increase of the working medium to above 565°C. In some cases, the water vapour is used with a temperature of up to 600°C. In the case of using steam in the state of supercritical parameters (610°C/30MPa), compared to the current water vapour parameters (540°C/18MPa) it is possible to achieve an increase of effectiveness of energy devices by up to 8 per cent at the current decrease of CO 2 emissions by up to 20 per cent.

Zeleziarne Podbrezova is adapting to the requirements of the segment,

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Tube Products International January 2013

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