AIC saves prime aircraft manufacturer over
£48,000 per year and benefits the environment
AIC Group has enabled a prime aircraft manufacturer
to save over £48,000 per year from the running costs
of one of its autoclaves, and at the same time reduce
the amount of propylene glycol used by 24,500 litres
annually. Just as importantly, the time taken to
complete the project was minimised, so that the
machine could be quickly brought back into
production.
The work involved upgrades to the autoclave,
comprising: a water cooling upgrade; pipework
replacement; and replacing the air blast coolers.
Water cooling upgrade
AIC’s work involved replacing the existing autoclave
cooling system with a more efficient water cooling
system to overcome problems of leakages and
corrosion caused by additive reactions within the
existing system.
1 Schematic of Advanced Cooling System
The upgraded water cooling system delivered the
significant reduction in chemical usage which contributed to the aerospace company meeting its
environmental targets with running cost savings as well as energy cost savings. This new
system allows for untreated pure water to be used, eliminating the risk of ground contamination
from glycol leaks.
AIC’s advanced fresh water cooling system has been developed from its extensive experience of
autoclave design and maintenance. This experience has been gained in aerospace, defence and
motorsport industries.
Environmental impact is a key feature of the design which eliminates the need for large
quantities of coolant and additives. This also has a considerable financial benefit, significantly
reducing chemical costs by as much as 98%, which includes disposal costs.
A fresh water tank provides frost protection with an immersion heater which automatically
switches on at temperatures below 5 °C monitored, via an air temperature probe.
AIC’s design allows for smaller Glycol cooling circuits , containing additives which are only
necessary for the protection of critical equipment including coolers, heat exchangers and
pumps.
Pipework
The new parts of the systems consist of welded stainless steel pipework to eliminate any risk
from galvanic stripping by chemicals. The previous autoclave pipework had been over 10 years
old and was at the end of its serviceable life. It was constructed from galvanised steel and had
corroded in several areas leading to multiple chemical leaks.
The new pipes are made of 316L stainless steel, which provide prolonged longevity of service.
The specification of stainless steel also allowed for ‘clean’ welds which will not leave burr
residue inside the pipe that could potentially damage the water cooling system.
The cooling to the fan motors run on an automated control system which initiates pumping of
coolant when any motor reaches 30°C and will continue circulating coolant for 20 minutes from
the time the air circulation fans stop to ensure their temperature returns to normal. The motors
are protected by flow switches which initiate alarms in the event of reduced coolant flow.
Air blast coolers
The final part of the upgrade, the replacement of the air blast coolers, also gave savings in
energy and high cooling performance.
A new inline independent air blast cooler removes heat from the system which is supplied by
duty and standby pumps. The cooler motors run on a randomised basis to reduce power
consumption and wear.
Tim Denison, AIC’s Operations Director, said: “This cooling system upgrade will greatly enhance
the integrity and reliability of the plant installed and increase the availability of the Autoclave
for production. It will accomplish this whilst also being.”
Nigel Clifford, AIC Director of Sales said “It was a complicated job but through careful
assessment and specification we were able to design a solution that delivered environmental
and commercial benefits and I am pleased we were able to complete the project one time to
minimise down-time.”