If your industrial air compressor is leaking oil, that’s a situation that needs to be taken care of right away. Learning how to stop oil leaks in your compressor through careful inspection, leak detection, and prompt repairs is essential air compressor maintenance. This blog post covers key steps for identifying and fixing common sources of compressed air oil leaks.
How Does Oil Leaking Impact Compressed Air Systems?
Oil-flooded rotary screw or reciprocating air compressors are complex machines that depend on compressor oil to lubricate and cool moving parts in the air end or cylinder and piston assembly and provide a seal to prevent air leaks. The lubrication system is essential to prevent compressor overheating, reduce wear and tear, and extend the lifespan of the compressor. A leak in the oil lubricating system leaves the compressor vulnerable to damage, poor performance, and other problems caused by low oil levels.
Here are some problems that result from oil leaking in compressed air systems:
Reduced Efficiency
Oil leaks can reduce the efficiency of the compressor. The compressor may have to work harder to maintain the desired pressure, leading to increased energy consumption and operational costs.
Contamination of Compressed Air
Oil leaking into the compressed air can contaminate the air being used in the process. This is particularly problematic in industries where air quality is critical, such as in food processing, pharmaceuticals, and other industries requiring clean, oil-free air. Excess oil can also cause problems for the air dryer and filters.
Increased Maintenance Costs
Frequent oil leaks can lead to higher maintenance costs and wasted money. This includes the cost of the oil itself, labor for repairs, and potential downtime during maintenance.
Equipment Damage
Prolonged oil leaks can lead to damage to the compressor and other related equipment. For example, oil can degrade rubber seals, o rings, and hoses, leading to further leaks and breakdowns. If the oil level in the air compressor is too low, excess heat will eventually cause damage to the air end or pistons.
Reduced Lifespan of the Compressor
Consistent oil leakage can shorten the lifespan of the air compressor by causing undue wear and tear on the air end, pistons, engine, and other components.
Operational Downtime
Significant leaks might require the air compressor to be shut down for repairs, leading to operational downtime and loss of productivity for the factory or workplace.
Environmental and Safety Concerns
Leaked oil can pose environmental hazards, especially if it contaminates the ground or water sources. It also presents a safety risk in the workplace, as it can make surfaces slippery and increase the risk of accidents.
Signs of an Oil Leak in an Air Compressor
Regular maintenance and routine inspections are essential for identifying and addressing these potential leak points in both rotary screws and reciprocating air compressors.
While obvious signs here are some common signs to look for:
Visible Oil Traces
Look for oil residue on the compressor's body, particularly around seals, o rings, gaskets, hose connections, and fittings. In rotary screw compressors, check around the air end and the oil separator. In reciprocating compressors, inspect the cylinder and pistons.
Oil Puddles or Stains
Excess oil on the floor beneath your compressor isn’t just a mess – it’s a potential problem. Check the floor beneath and around the compressor for any oil puddles or stains, indicating oil leaking from above.
Decreasing Oil Level
Regularly check the oil gauge and monitor the oil level in the compressor. A faster-than-usual decrease in oil levels can indicate a leak. If you find yourself having to fill the lubrication system more frequently than usual, you should suspect a leak.
Oil in Air Lines
For rotary screw compressors, which often use oil-injected technology, finding excessive oil in the airline or air receiver tanks can suggest a leak in the oil separator or related components. In reciprocating compressors, this is less common but can still indicate issues with internal seals or gaskets.
Unusual Noises or Performance Issues
Listen for any unusual noises from the compressor, as leaks can sometimes cause changes in operational sounds. If the compressor struggles to maintain pressure or shows other performance issues, it could be related to an oil leak affecting its efficiency.
Oil Mist or Fumes
In some cases, an oil leak can create a mist or fumes around the compressor, especially when the machine is running.
Deterioration of Seals or Hoses
Inspect seals, hoses, and connections for wear and tear, as deteriorated components are common sources of leaks.
Where Air Compressor Oil Leaks Develop
Oil leaks in air compressors can develop in several locations, and the specific areas prone to leaks can differ between rotary screws and reciprocating compressors.
All Compressor Types
Common areas where oil leaks may develop in all compressor types include the following:
- Drain valves: Drain valves, if not properly closed or if damaged, can lead to oil leaks.
- Pressure relief valves: These valves can develop leaks if they malfunction or are damaged.
- Gaskets and seals: Across various components, deteriorating gaskets and seals are frequent culprits for oil leaks.
- Oil line, fittings, and hose connections: Oil lines and connections between the oil return line and other components can become loose or worn, leading to leaks.
Oil Leaks in Rotary Screw Compressors
Rotary screw compressors typically have more complex oil systems, so leaks may occur in various components like the air end, oil cooler, or separator.
Look for oil leaks in:
- Air end seals: The air end in a rotary screw compressor has seals that can wear out over time, leading to oil leaks.
- Oil cooler and lines: The oil cooler and associated lines are common areas for leaks due to constant exposure to high temperatures and pressures.
- Oil separator: The oil separator, which removes oil from the compressed air, can develop leaks, especially around its seals and gaskets.
- Oil filter and housing: The oil filter and its housing can become sources of leaks if they become loose or the seal deteriorates.
Oil Leaks in Reciprocating or Piston Compressors
In reciprocating compressors, leaks are more likely around the piston, valves, or any oil lines connected to the cylinder.
Some common oil leak locations include:
- Cylinder head and valve plate: The gaskets between the cylinder head and valve plate can degrade, resulting in oil leaks.
- Piston rings: Worn or damaged piston rings can allow oil to escape the piston area.
- Oil sump: The oil sump or oil reservoir in some designs might develop leaks, especially around seals or gaskets.
- Crankcase: The crankcase, particularly around its seals, can be a common site for oil leakage.
Choosing the Right Compressor Oil
One hidden cause of air compressor oil leaks? Using the wrong compressor oil. If the lubrication does not meet or exceed manufacturer recommendations, you could experience negative effects including oil carryover, oil breakdown, carbonization and varnish, premature seal wear, and shorter equipment life. Premature wear of seals and other components can cause leaking in oil-flooded compressors. That’s why it is very important to choose the right compressor oil for your machine, following manufacturer recommendations.
How to Fix Oil Leaks in Air Compressor
Oil leaks in an industrial air compressor should be taken care of promptly. While adding extra oil is a temporary solution to prevent immediate overheating and damage, it is important to locate and fix the source of the oil leak to ensure equipment longevity. Remember, while some oil leak repairs can be handled in-house, particularly if they are minor, complex issues, especially in critical components like the air end of a rotary screw compressor, may require professional servicing to ensure a proper and safe repair.
For rotary screw compressors, pay special attention to the air end, oil cooler, and oil separator, as these are common leak points. Be cautious with the air end; it's a critical component that will typically require professional servicing.
For reciprocating compressors, focus on the cylinder head, valve plate, and piston area for any signs of oil leakage. Ensure the piston rings and the crankcase are in good condition and replace them if necessary.
Fixing oil leaks in both rotary screws and reciprocating compressors involves a series of steps that are somewhat similar for both types, although the specific parts requiring attention may vary. Always consult your user manual before making repairs to your industrial air compressor.
Here's a general guide:
1. Identify the Source of the Leak
Carefully inspect the compressor to locate the exact point of the oil leak. Common areas include seals, gaskets, hose connections, and fittings.
2. Depressurize and Power Down
Ensure safety by turning off the compressor and relieving any built-up pressure before beginning repairs.
3. Clean the Area
Clean the area around the leak to ensure a clear view and to allow for a proper seal during the repair.
4. Replace or Repair Faulty Parts
Replace worn or damaged seals and gaskets. Make sure to use parts that match the compressor’s specifications. Check for cracks or wear in hoses and replace them if necessary. Ensure all connections are secure.
5. Tighten Connections
Sometimes, simply tightening loose bolts or fittings can resolve the leak. For threaded connections, you may use thread sealant tape or a suitable liquid thread sealant if indicated by your user manual.
6. Reassemble and Test
After making repairs, reassemble any disassembled parts, turn on the compressor, and observe if the leak persists.
7. Check Oil Levels
After the repair, check and adjust the oil level according to the manufacturer’s specifications.
8. Monitor Performance
Observe the compressor for a while to ensure that the issue has been effectively resolved.
Need Repair for Air Compressor Leaking Oil?
Fluid-Aire Dynamics is your service partner for industrial rotary screws and reciprocating air compressors. If your compressor is leaking oil, or exhibiting other performance problems, contact our service department for assistance. We can help you keep your compressed air system operating at peak performance with preventative maintenance and 24/7 air compressor repair services.
Schedule a service appointment today.
