Temporary chiller hire: Boost to productivity
09 January 2014
When repairs are needed to cooling equipment a hired chiller can provide an efficient solution, as Carl Webb, director of Andrews Chiller Hire, explains
Water is at the heart of so many industrial processes; they rely heavily on the cooling nature of this underrated and often taken for granted commodity to deliver and maintain correct temperatures during manufacture or storage. There is a wealth of processes where the absence of a controlled water temperature could jeopardise productivity and quality.
Take for instance plastic component manufacture. Here chilled water may be used to cool the actual injection moulding machines to prevent overheating as well as being used to lower the temperature of the finished component. In cider production, chilled water is used to maintain a constant temperature in the fermentation process; however it is during bottling that chillers are mainly used as CO2 dissolves better in colder water. It is also essential to uphold a strict temperature at this stage to prevent the cider from 'fobbing': when a drink's head is too big and frothy.
These two industrial processes are poles apart but both are reliant on water at a constant controlled temperature. When the supply stops it can have a major financial impact on profitability, and in these tough economic times it could mean loss of one or two contracts, with implications that could lead to business closure unless a solution is quickly found. At such times, on-site maintenance engineers are under extreme pressure to resolve the situation, it could be simply a stuck valve or a more serious incident where the plant delivering the constantly chilled water has developed a major problem that could remain unsolved for many days.
While major repairs take place, the prime alternative is chiller hire. It is a cost-effective solution and hiring from a well-established organisation, such as Andrews Chillers, with a nationwide network of hire depots and an experienced engineering team could mean your business is just hours away from being back into production.
Hiring a chiller
While many hire organisations will claim to provide 24/7, 365-day access to specialist engineering staff, just a few can deliver on this promise. These have a large nationwide network of depots that can respond promptly as, in an emergency situation, the customer faces the possibility of losing many thousands of pounds through machine downtime or waste product.
Engineers from competent hire companies need to carry out a survey to identify the best position to site a skid-mounted chiller, understand the chilling requirements and specify a chiller capacity that must also take into account ‘heat’ and ‘cooling’ losses from lengthy pipe runs, the greater the distance to the site inlet manifolds the larger the unit and subsequent higher costs.
Air-cooled, fluid chillers are available from most hire companies. Hire companies like them because they are easy to service which means customers are guaranteed to receive fully tested and maintained chillers which can be installed more quickly than water-cooled machine, enabling the production process to return to normality.
Air cooled chiller design
During operation the flow of the warm hot process water enters a chiller barrel (also known as the chiller evaporator) which also receives the system's cool low pressure mixture of liquid and vapour refrigerant, this absorbs the heat from the process liquid. This transfer of heat boils the liquid refrigerant in the chillers evaporator and the super-heated vapour is pulled into a chiller's compressor. This compresses the refrigerant to a high temperature and pressure, high enough to allow the chiller's condenser (a heat exchanger) to reject heat from the chiller's refrigerant to the atmosphere, axial fans (propeller type) drawing outdoor air over a finned tubed heat transfer surface (heat exchanger).
Since the efficiency of an air cooler chiller relies on expelling heat into the atmosphere, correct position of the hired chiller is paramount. For any competent chiller hire company correct placement of the chiller should be second nature.
Choosing the right hire company can certainly pay dividends – quicker response to cooling problems, competent engineers, faster delivery – and above all temporary installation of the right chiller to enable the production process to re-start.