Proactive maintenance, better compressor efficiency
15 March 2021
Lockdowns, operating restrictions and social distancing might mean that, for some businesses, compressed air maintenance has been neglected. This could negatively impact the expected life of compressed air equipment and its overall efficiency. Gary Spence offers advice on maintenance checks that can help maintain and improve the energy efficiency levels of a site’s compressed air system
COMPRESSED AIR is often referred to as the fourth utility. It is essential to many sectors as a safe, reliable and versatile source of power. However, it can take a considerable amount of energy, generally in the form of electricity, to produce compressed air. This can be seen in the sheer volume of energy required to meet the UK’s compressed air demands. The nation’s industry uses over 20TWh of electricity to compress air – the equivalent to the output of four power stations. Indeed, generating this huge quantity of compressed air accounts for ten per cent of the industrial sector’s total energy costs.
In order to optimise a compressor’s efficiency levels, there are a range of maintenance strategies, both predictive and preventative, that owners and operators can implement.
The more comprehensive maintenance strategies employ a supply side audit, which can help identify equipment and system inefficiencies and ensure these are managed effectively. These are helpful because they can provide owners and operators with a clear picture of how much these inefficiencies cost, while identifying opportunities to improve productivity, safeguard product quality and reduce site downtime.
Air leaks are the leading cause of energy loss in industrial air systems, wasting as much as 20 to 30% of the system’s output. In fact, the Carbon Trust reports that a leak as small as 3mm can cost over £700 in wasted energy. There are many reasons for leaks in a compressed air system, including shut-off valves and manual condensate valves being left open, as well as leaking hoses, couplings, pipes, flanges and pipe joints.
Another area is compromised piping, as this can lead to compressed air contamination. Unsealed joints, cracked pipes and open valves letting air out can also let moisture and contaminants in via osmosis. This can result in reduced productivity levels, downtime and potentially product spoilage. Leak detection is often employed to determine the integrity of the compressed air piping network. Benefitting from this, however, requires a commitment to remedying the leaks identified. Meanwhile, implementing a thorough maintenance regime based off these findings can reduce the likelihood of blocked inlet and downstream filters and contamination, delivering lower overall running costs.
The layout and age of a compressor’s pipe layout can also compromise overall compressor performance and is another area that an energy or supply side audit will consider. For instance, old or incorrectly sized pipework can result in pressure loss, reducing the efficiency of a system. This is also the case for set-ups that include too many bends, tees or fittings. Any loss in air pressure must be compensated for by the compressor expending more energy to generate the same volume of compressed air.
One company that has benefitted from an energy audit in recent years is plastics company BPI, at its Heanor facility in Derbyshire. A detailed report helped the company replace its old dryer system with a more energy-efficient solution that paid for itself in just one year. BPI replaced its 10 point-of-use purged desiccant dryers with a single CompAir A488TVT Zero Purge desiccant dryer. Replacing these dryers with one efficient, highly reliable unit reduced BPI’s maintenance costs considerably.
Andrew Terry, engineering manager at BPI Heanor, said: “We now use one central machine to ensure all air is dried properly throughout the site, which makes for a big increase in terms of reliability.”
Keep it genuine
All compressed air systems will require components such as filters, valves, seals and oil to be replaced. To assure the efficiency of a compressor, however, it is critical to stress the importance of investing in genuine spare parts and lubricants, rather than non-genuine alternatives.
Non-genuine filters, for instance, are more likely to have reduced dust and dirt-holding capacities, which means contaminants can easily enter a system. Also, a non-genuine lubricant can place extra demands on the filter element, resulting in dust and other particles coming into contact with internal compressor components, invariably leading to mechanical performance deterioration. In both cases, blocked filters also cause some level of deterioration in energy efficiency performance.
Genuine parts are manufactured to meet the same standard as the compressors that they are intended for. The same is true of genuine lubricants, which are formulated with additives to enhance compressor performance, while ensuring the correct lubrication, cooling and anti-wear qualities are maintained.
Take advantage of insights
Industry 4.0 technology is creating a real opportunity for compressed air users to consider how data can help improve compressor performance and highlight any inefficiencies. These insights not only help highlight any immediate issues, but also enable operators to forecast for any potential future problems, based on deteriorating machine performance. Furthermore, predictive maintenance models based on real-time data can be established to help reduce energy consumption, improve process efficiencies and limit any risks.
Digital platforms can help provide tangible benefits to a business’ bottom line, with real-time monitoring, alarms and warnings to reduce the risk of downtime. Cloud-based systems mean remote sites can be easily monitored, and compressor performance can be optimised with machine parameters and trend analysis over time.
One consideration to bear in mind is that businesses, over the years and various product lifecycles, may have purchased from many different brands. Indeed, even if a site has been loyal to a single manufacturer, there are no guarantees that they won’t switch suppliers in the future.
In order to easily and efficiently connect with IoT technology, all of these machines should ideally be producing data that comes in the same format and complies with the same standards, regardless of which company supplied them. Essentially, they should all be speaking the same language.
However, as things stand, too many systems out there are running on proprietary protocols and standards. This locks up their data in a way that makes it awkward and inconvenient to process, limiting the ways in which machines can interact with IoT technologies.
Open platforms are available, however. For example, CompAir has developed iConn, a cloud-based, air management platform that delivers advanced analytics, enabling operators to stay in control of their compressed air installation at all times. Crucially, iConn is also an open platform, supporting ancillary and compressed air products from other brands. iConn can help provide a platform that delivers truly meaningful compressed air insights, no matter who the manufacturer is.
It should go without saying that on-going servicing and maintenance is necessary to make sure equipment runs reliably and efficiently. Investing in an intelligent service program with a proven and trusted compressed air supplier, who can ensure optimum maintenance interventions and service are executed to the highest standards, will help provide long-lasting peace of mind.
It’s worth noting that there are many benefits to be gained from working with a single supplier for all of a company’s industrial air needs. Should a site not only have a compressed air system but potentially vacuum pumps and blowers too, then this means all the equipment can be covered under one comprehensive maintenance agreement. This minimises any disruption to a business’ operations, while also helping to reduce administration time and cost.
By following these recommendations, operators can expect to considerably improve the efficiency of their compressed air systems.
Gary Spence is service operations leader – Europe for compression technologies and services at CompAir