STEAM SYSTEMS
A steam system survey This is where bringing in a third party can make a big difference. As part of an annual steam system survey, facilities management companies or steam system specialists take a holistic view of the process. They are then able to establish where and what needs to be done to keep it running efficiently, or to get it back to an efficient state. This audit or steam system survey is often part of a wider service contract, designed to limit backlog maintenance, with a single annual fee covering any and all maintenance required on site. However, as with any service contract, often a ‘one size fits all’ approach isn’t the best use of funds or resources. Increasingly, modular service contracts – which offer various levels of knowledge, time, and expertise – are being used by hospitals. Instead of offering an off-the- shelf model, companies like Thermal Energy are helping hospitals build a service contract to suit them. The flexibility offered by modular service contracts is what makes it particularly applicable to the health service, and a vital part of the solution to the sector’s backlog maintenance problems.
Based on the site requirements, service and maintenance agreements can be tailored to cover everything, including surveys, call-out days, parts, and even the management of additional suppliers, such as water treatment specialists. Alternatively, a bespoke service contract can focus on training and maintenance. It can be designed to support and educate an ‘in-house’ team at the hospital on the general running of the system. If the team
130.5 Max = 123.8 Max = 134.5
117.0 108.0 99.0 90.0 81.0 72.0 63.0 54.0 45.0 36.0
26.1 ˚C
A failed open trap. If a trap is discharging into an atmospheric condensate return system, the temperature downstream of the trap should be below 100˚C. The thermal images show the downstream temperature is over 100˚C, indicating that live steam is passing straight through the trap and pressurising the condensate return system. These traps have failed open, and would need to be replaced.
has capacity, this solution can help to minimise backlog maintenance, since potential issues are identified internally, before they become a problem. Usually a thorough ‘walk-through’ of the system is enough to recognise the most pressing maintenance activities. Hospitals simply need to be aware of what they are looking for.
All the trappings of a safer system If a steam system is not adequately maintained, one of the most damaging
An example hospital
n 400-bed hospital has an hourly steam requirement of 3 MW. n This would require, on average, approximately 150 steam traps on site. n Each year, an average of between 5% and 10% of mechanical steam traps fail. n Replacing failed traps costs the estate £5,000 in maintenance each year. n Without regular review, over five years this bill can grow to over £25,000, and threaten pipework and other infrastructure.
n This issue also results in major downtime of the heating and hot water systems.
impacts is water hammer, sometimes known as steam hammer. This occurs when condensate that has not been effectively drained is picked up by the steam, sending it through the pipework at high speed. It creates a loud ‘hammering’ noise which can be heard throughout the site, disturbing both patients and staff. More significantly, it wears away at the pipework. If left unattended, water hammer can have disastrous consequences. Some sites have experienced ruptured pipework as a result, which has major health and safety implications. Steam trapping, which removes air and condensate from the system as they form, is key to minimising the risk of water hammer and maintaining a safe and efficient system.
The steam traps themselves need to be maintained to ensure that they are operating correctly. Failed traps not only waste energy, as they can result in live steam loss, but in the case of preventing water hammer, instead of condensate
February 2019 Health Estate Journal 65
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 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69
