Compressed air systems offer many advantages, including improved economy, reliability, and energy efficiency. Their ease of use and versatility enable complex tasks to be completed more quickly compared to other power tools so, when technical problems occur, time, productivity and energy can be wasted.
Fortunately, some of the problems that affect compressed air systems are not complex and can be solved by taking some straightforward steps.
Problem 1: Pressure Loss
Loss of pressure affects the system’s ability to operate at optimum power, so it ceases to be as efficient or cost-effective, especially if the user attempts to compensate by increasing the pressure from the generator.
Most often, pressure is lost between the distribution header pipe and the compressed air powered equipment. All end-use components in-between – connectors, filters, hoses and regulators – should be of an appropriate size to prevent pressure loss.
Alternatively, significant pressure loss may be experienced in the compressor room. Components such as the main system filters, air dryer, air or oil separators and coolers must be of the correct size and regularly maintained. Filters should be regularly cleaned to prevent them from accumulating loose particles.
Finally, undersized piping throughout the pneumatic system can occasionally cause loss of pressure, particularly if the plant has been expanded gradually but the existing piping has not been upgraded. At peak production times, there should be a maximum loss of less than two psi, which can be achieved by installing the appropriate size piping. Where possible, avoid using elbows in the pipework and install low resistance valves, such as full flow ball valves, to reduce resistance.
Problem 2: Leaks
Small leaks in compressed air systems are common but cause significant loss of energy. Identifying the location of a leak could be as simple as listening for the escape of air (start at the compressor and walk along the line) or using leak detection fluid which bubbles if air is escaping; alternatively, an ultrasonic leak detector is a valuable tool to detect the source of a leak.
Knowing where common leaks occur could help you identify the location in your system. Most leaks occur at valves, regulators, filters, flanges and condensation traps, or connection points in the main distribution system. Deterioration around pipework joints and worn snap connectors are also common causes of leaks.
Identifying and repairing leaks will help reduce the energy your system consumes and extend its lifespan.
Problem 3: Over-pressurisation
Reducing pressure in a compressed air system can increase its efficiency and reduce operating costs (a 1% saving for each reduction in pressure by 2 psi is realistic). Higher pressure levels do not always produce better results but, despite this, many industrial plants insist on running their systems at a much higher pressure than is required. Excessive pressurisation may be a result of user error, overcompensation due to unidentified leaks in the system, a shortage of storage or poor pressure control.
Regular maintenance will help to identify hidden leaks and deterioration in pipework, filters, valves and other components, which will reduce the need to artificially increase the pressure to compensate. Pressure gauges should be carefully monitored, and pressure maintained at the lower end as often as possible, while pressure regulators installed across the system will also be beneficial. Avoid pneumatic tools that require high pressure – demands of over 90 psi will only cause your system to work harder and burn more energy in the process.
Problem 4: Overheating
Overheating can occur for several reasons, but prevention is the main solution to the problem. Rather than cooling an overheated compressor, focus on preventing it from happening in the first place. Ensure that all vents are clean and an appropriate size (especially if you have expanded your plant over time) and make sure there is adequate ventilation in the room where it is housed.
Also, oils and lubricants must be topped up regularly as these help to cool the system. Most problems with compressed air systems can be prevented by implementing a regular schedule of maintenance that ensures defects are identified early and addressed, as well as ensuring that users understand the most efficient ways to operate the system without unnecessary loss of energy.
Find Out More
At Hydrastar we design and maintain bespoke hydraulic and pneumatic systems for a wide range of applications. To find out more, please call 01353 721 704.