General manager of instrument hire company Ashtead Technology, Alan Hasson has a wealth of experience in helping customers minimise plant shutdown. Here, he cites examples where test and inspection engineers have employed instrumentation to reduce risk and cut costs

Engineers routinely employ a wide range of test, inspection and monitoring technologies to check that equipment is in good working order to avoid machine failure and plant shutdown.

Equipment usually gets hot before it fails, so infrared cameras are commonly employed for such purposes in addition to a wide array of other non-destructive test equipment.

Similarly, environmental and process monitoring equipment can help identify potential problems before they affect the plant or process.

However, there are many other instances in which such instruments have saved time and money. Endoscopes enable the internal inspection of equipment, thereby avoiding the costs and delays that would have been incurred by dismantling.

For example, if that equipment is a ship’s engine, the time saved can substantially reduce mooring and ‘out of service’ costs. In other examples, Ashtead equipment has been used to prove that there was no damage to the internal components of aircraft engines following a flight through the Icelandic ash cloud.

Cooling tower inspections include a physical examination of the cooling pack to check for scale, slime, algae and physical obstructions, any of which could harbour Legionella bacteria as well as hamper the performance of the cooling system.

In the past, it has been common practice to remove the cooling pack for the purposes of the inspection and cleaning (regardless of whether the tower needed to be cleaned or not). This can be a lengthy procedure during which the cooling system would be shut down.

However, Ashtead customers have demonstrated that effective inspections can take place without having to remove the cooling pack. This has been achieved with the use of a hired high-resolution iPLEX videoscope. This enables the inspection of the internal components of the tower from top to bottom using a small access point. The probe can extend up to almost 10m, providing clear video images that can be stored or transferred to a PC.

One of the key features of the iPLEX range is the quality of images that are generated.

Images with a limited dynamic range tend to lose detail in the brightest and darkest areas.

However, the iPLEX instruments have virtually eliminated such whiteout and blackout through a newly developed, proprietary image-processing algorithm that expands the dynamic range. The resulting rich gradations naturally represent the inspection area as seen by the naked eye, allowing more accurate inspection.

In this example, hired videoscopes can reduce cooling tower inspection times, and thereby minimise shut-down times from as much as 2 days down to as little as one hour.

In a further example, portable gas analysers helped a consultancy firm save a client almost £500,000 by preventing the shutdown of an incineration plant.

Environmental legislation dictates that emissions from incinerators have to be continuously monitored, so when a problem occurred with the on-line analyser at a municipal waste incinerator, it was important that a solution was found quickly so that the plant could continue to operate.

Coincidentally, staff from Cardiff and Birmingham-based Environmental Compliance were onsite carrying out compliance monitoring at the time and immediately contacted Ashtead Technology to arrange an urgent next-day rental for two Horiba PG250 portable multi-gas analysers.

Rhodri Jones, senior team leader at Environmental Compliance, said: “What began as a typical ‘QAL2’ compliance monitoring session quickly transformed into a potentially serious situation for our client.

Thankfully, Ashtead was able to guarantee delivery of the Horiba PG250s to our client’s site the following day.” In summary, almost all test, inspection and monitoring equipment can help to avoid plant shut down and with technology constantly changing, the technical support engineers at Ashtead have been trained to provide help and advice on appropriate equipment for each application.