Newsletter Issue 21 - JT Day Pty Ltd

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Two ships fitted and one to go with the unique Hawke Transit System Delivery of supplies of Hawke Transit Systems from JT Day for the three new Hobart Class Air Warfare Destroyers has been proceeding steadily. Supplies have been delivered for two ships with another due for supplies when construction work is ready to receive them. The three destroyers are being built for the Australian Government by Adelaide-based shipbuilder, ASC. ASC chose the Hawke Transit System to maintain integrity of bulkheads and the deck areas through which electrical cables and piping pass as the transit system is a particularly good product for pressure sealing against fire, water and gas. One of the unique aspects of the Hawke Transit System is colour coded blocks that Hawke’s unique colour code system ensure the top and bottom halves of each block are correctly matched for size so that the chances of errors can be minimised. These blocks in seven sizes ranging from 3mm to 100mm in diameter have been designed with a degree of flexibility to accommodate variances in cable diameters. As a consequence they offer a simpler, speedier process of installation than that offered by other systems. These size-tolerant blocks are made of zero halogen, intumescent elastomeric polymer with five sealing faces that are displaced by the sealing process to give a tolerance of up to 4mm for cable diameters. Meanwhile the Federal Government has announced that the $36billion Future Submarines project will be going ahead, also based in South Australia. The project will be the largest and most complex Defence project ever undertaken by Australia, involving hundreds of companies and thousands of workers. LED lighting They’re here to stay THERE’S NO DOUBT LEDS ARE NOT A PASSING FAD Traditional products like fluorescents, floodlights, bulkheads, and wellglasses using traditional lamp sources, such as fluorescent or HID, will not disappear overnight but with the continuing improvements in LED technology, this new light source is proving to be ideally suited to oil and gas installations because of safety factors and reduced energy usage. Ian MacLeod, a spokesman for Chalmit Lighting, our principal supplier of lighting for the oil and gas industry, makes the point that whether using older or newer technology there are pros and cons to the best use of products, dependant on many factors, ambient temperature, installation cost and maintenance costs, to name just a few. Chalmit has been manufacturing Ex LED products since 2004. Their Nexled bulkhead light was the first hazardous area product utilising LEDs as the main light source. Over 10,000 have been installed worldwide. The first ventures into LEDs concentrated on smaller products using low to medium power LEDs, but as the technology has improved their designs have been scaled up to give products delivering output to match fluorescent and HID lamps. Ian MacLeod said that in designing with LEDs it is important to ensure they do actually perform as expected – putting the required amount of light (lux) on the working plane. In order to ensure designers and users can be assured of the right product for the job, Chalmit releases photometric details that provide an indication of the levels of light output. Another important factor with LED products is the life, not only of the LED but of the complete luminaire. Chalmit has a long history of designing and manufacturing products that are robust and suitable for the challenges thrown up by oil & gas installations and have used the knowledge to ensure that the key parts of any LED luminaire – the LEDs and the driver – can cope. Another benefit of LED technology is that the components are similar worldwide. No longer are there situations where European lamps and control gear differ from US lamps and control gear – they’re all using similar solid state technology. In the very near future Chalmit will have a full range of Ex products utilising LEDs. When these are added to the already extensive range of Ex products using existing lamp sources, the range of choices will be huge. 2 Reliability Dependability Quality
Why earthing is important By Paul Hollingsworth, CEO Lightning Protection International The installation and maintenance of an effective low resistance earthing system is essential for any modern facility for three key reasons: ▪▪ ▪▪ ▪▪ Protection of personnel Protection of equipment Ensuring electrical noise reduction to minimise voltage potentials between interconnected equipment The requirement for effective earthing is critical when considering the following applications: ▪▪ ▪▪ ▪▪ ▪▪ Lightning protection Power generation, distribution and transmission Telecommunications Reduction of static electricity The key parameters of an efficient earthing system In order to achieve a low resistance and impedance, earth connections should be short and direct as possible. Maximising the surface contact between the soil and all electrodes and conductors is essential for efficient performance. The system needs: ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ Excellent electrical conductivity Low earth resistance and impedance Conductors capable of withstanding high fault currents Robust mechanical connections to facilitate a long working life High corrosion resistance Materials chosen for earthing systems should offer an acceptable compromise between cost and longevity. Compatible metals must be used to minimise corrosion. ▪▪ Equipotential Bonding The elimination of dangerous step and touch potentials is achieved through equipotential bonding of all earths. The importance of low soil resistivity The resistance of the earth itself (earth / soil resistance) is the greatest influence on overall impedance of an earthing system. Factors such as soil composition, moisture content, seasonal weather, mineral content and possible contaminants determine resistivity. Moisture content is the single largest influence and in most cases, the higher the moisture level the lower the soil resistivity. The installation of a deep driven earthing electrode that reaches the water table beneath the surface represents an ideal earthing system. ▪▪ ▪▪ ▪▪ Rich dark soils high in organic content are typically good conductors due to moisture retention which aids in the dissipation of electrical currents. Sandy soils are ineffective in retaining moisture and typically have higher impedance. Rocky ground retains virtually no moisture and is very high in resistance. Designing an earthing system There are several factors to consider when planning the design of an earthing system. ▪▪ Applicable standards and codes to be followed: For power system earthing IEEE 80 or other international derivations are widely used. These standards are usually mandatory and some level of expertise is needed to undertake designs to these standards. For lightning protection / static earths commonly used standards are IEC62305, AS1768, NFPA 780. These are often not mandatory but provide recommendations. ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ ▪▪ Type of facility and the site layout in regards to available space Level of soil resistivity at site Influence of seasonal weather conditions on soil resistivity Corrosive nature of soil and consequently materials chosen for use Expected life of the facility will affect material choices Future extensions If applicable the status of any existing earthing system Step and touch potentials Volume of pedestrian traffic Finally, but most importantly, the quality and compliance of hardware used in the earthing system installation is a major determinant of the reliability of the earthing system. This is why some standards for design also have requirements associated with testing and certification of components. Some applicable testing standards include IEEE 837, and EN 50164. Footnote: JT Day has signed a distribution agreement with LPI for earthing/direct strike products for the oil & gas market. Reliability Dependability Quality 3
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Newsletter Issue 21 - JT Day Pty Ltd

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