PLANT MANAGEMENT
TFS recently launched two semi- synthetic heat transfer fl uids with a fl ash point of over 260°
HEAT TRANSFER Safer approach to
Richard Franklin offers some advice on how best to maintain thermal fluid system assets to prevent the risk of explosion
heat around their manufacturing plants. Legislation stipulates that these fi rms must proactively monitor and maintain their thermal fl uid system assets to prevent the risk of fi re or explosion. The implementation of a continuous
A
risk assessment and preventative maintenance programme can help fi rms to save money as well as lives. And the fi rst critical part of a successful programme is to regularly monitor the condition of thermal fl uid. The heat transfer media used in
thermal fl uid systems are typically mineral or synthetic oils. A system’s operating temperature is invariably higher than the ‘closed cup fl ash point’ of the media – the minimum temperature at which, in the presence of a source of ignition, such as light
24
www.engineerlive.com
n estimated 3,000 companies within the UK’s process industries alone operate thermal fl uid systems to transfer
switches, pump failure or sparks, the fl uid’s vapours will ignite. Where heat transfer systems operate
under high pressure, any leaks from the pipework at points such as fl anged joints, valves and connection points, can create mists or sprays, which result in the creation of an explosive atmosphere outside the system. Most thermal fl uids operate above
their fl ash points, and the systems that contain them must therefore be treated on a risk assessment basis. Whether inside or outside heat
transfer systems, on ignition, volatile atmospheres result in fi res and explosions, and European ATEX (Atmosphère Explosible) legislation – implemented in the UK via DSEAR (Dangerous Substances and Explosive Atmospheres Regulations) – stipulates requirements for the protection of workers against such incidents arising from the presence of hazardous substances in the workplace. PUWER (Provision and Use of Work
Equipment Regulations) dictates that all installations, including thermal fl uid systems, are operated correctly and properly maintained. Although most companies are aware
that heat transfer systems operating above the fl ash point of the fl uid must be maintained according to legislation, many do not appreciate that organic thermal fl uids based on mineral oils will degrade over time. Degradation can cause a fl uid’s fl ash point to decrease, as ‘light’ materials with lower fl ash points than the heat transfer fl uid itself are generated, reducing the fl ash point of the fl uid overall, so that fl uids that were not fl ammable at the operating temperature at installation, eventually become fl ammable. The legislation demands that the risks
inherent in the use of fl ammable fl uids are assessed and eliminated or reduced via a comprehensive preventative maintenance programme. Regular fl uid sampling and analysis is required to
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52