Your air compressor is a significant source of energy at your facility. An efficient compressor can save costs and use less energy than leaky systems. Compressed air leaks can increase your energy bill and cause you to need more maintenance and downtime to accommodate the loss.
If you suspect a leak in your compressor, it's essential to identify the problem as quickly as possible and address it before it creates significant downtime or productivity loss. Fortunately, discovering these leaks can be simple, and we can help you prevent these issues. Discover how much compressor air leaks are costing your facility and how you can fix the problem now.
In This Article
- Compressed Air Leakage Cost Calculator
- Other Losses From Air Compressor Leaks
- How to Locate Compressed Air Leaks
- Common Causes of Compressed Air Leaks
- Should You Fix Compressed Air Leaks?
- Fixing Compressor Air Leaks
- Preventing Compressor Air Leaks
- Contact Fluid-Aire Dynamics to Repair Air Compressor Leaks
Compressed Air Leakage Cost Calculator
A leaky air compressor is less efficient. It’ll use more energy and be less reliable than a compressor in perfect condition. Whether or not you realize your compressor leaks, you’ll pay for it on your energy bills. Exactly how much are your air leaks costing you? First, it depends on how much leakage you have. To estimate, follow these steps:
- Time how long it takes for your compressor to drop from its operating pressure (P1) to half of its operating pressure (P2), in pounds of force per square inch (PSIG). Write down the total time (T) in minutes.
- Subtract P2 from P1, and multiply that number by the total system’s volume (V), including all downstream receivers, piping and air mains, in cubic feet. Your manufacturer usually lists volume in gallons. To convert to cubic feet, divide the total gallons by 7.48.
- Take V multiplied by the result of P1 minus P2 and divide it by T times 14.7. Finally, multiply your answer by 1.25.
The leakage rate formula is [V * (P1 – P2) / (T * 14.7)] * 1.25. To keep things simple, let’s imagine a 5-cubic-foot compressed air system. Starting at 100 PSIG, it takes the system 60 minutes to reach the end pressure of 50 PSIG. Plug these numbers into the formula, and you get [5 * (100-50) / (60 * 14.7)] * 1.25. Do the math, and you’ll arrive at 0.354, or 35.4% leakage.
A normal system will experience 10% leakage, and anything above that is a sign you have leaks to patch. To understand how much your leaks are costing you, you’ll need to know how many leaks you have and the leakage rate. The Department of Energy (DOE) offers a useful chart to help you find the leakage rate for different diameters and shaped holes at your operating pressure.
Once you know these two numbers, you’ll also need to know how many kilowatts (kW) it takes to produce 1 cubic foot per minute (CFM), the number of hours your system operates each year and your energy cost per kilowatt-hour (kWh). The kW per CFM can vary slightly by machine and should be around 19 kW per 100 CFM, or 0.19 kW per CFM. You should know your energy cost from your energy bill. Otherwise, you can substitute the current national average for the industrial sector, which is around $0.07 per kWh ($/kWh). Multiplying all these figures together will give you your annual cost due to leakage.
The leak cost formula is the number of leaks * leakage rate (CFM) * (kW/CFM) * operating hours per year * ($/kWh). For example, let’s say you discover five 1/4-inch circular holes on a system that runs on 90 PSIG. According to the DOE leakage rate chart, your leakage rate is 89.2 CFM. Let’s also say your compressors run 7,000 hours a year, your energy costs $0.07 per kWh and your compressors use 0.19 kW/CFM. Following the formula, you would calculate 5 * 89.2 * 0.19 * 7,000 * $0.07. In this situation, the energy cost per year adds to $41,522.60.
Other Losses From Air Compressor Leaks
Leaky air compressors can cause an array of problems for your facility. According to the formula above, the compressed air leakage cost should indicate the cost issues you're facing.
However, there are several other factors you must consider to determine the effect of a leaky compressor. Take a look at the several areas in your compressor that could be harming your facility:
Operation costs for air compressors often outweigh the initial purchase total. Industrial compressors need significant amounts of energy. When these devices don't run at peak efficiency, the lost energy won't contribute to your facility.
This also means you will have to produce additional energy to compensate for what you've lost. For example, you may need to produce 130 CFM of air if you require 100 CFM at a leakage level of 30% to compensate for the loss. This could lead to costs between $30 and $90 per shift with a 1/4-inch leak, according to the Environmental Protection Agency.
Downtime increases as productivity decreases. Air leaks can result in unexpected failures and more frequent maintenance intervals — periods that will stunt regular processes. If your entire system relies on compressed air, frequent repairs and maintenance can cause work to pause for prolonged periods. Leaky, inefficient compressors need to cycle more frequently, creating a more frequent downtime routine.
Unnecessary Capacity Additions
Leaky compressors can expel between 20% and 30% of the air they generate. This could mean you're unable to use up to 30% of the compressed air your device produces. Some people opt for machines with the exact capacity amount they need, meaning your equipment and tools won't get the pressure they need if your compressor is leaking vital air.
When you identify a leak, you may need to source additional equipment to remain on schedule. This creates unnecessary purchases and takes up crucial floor space with another asset you must maintain.
How to Locate Compressed Air Leaks
You can sometimes hear compressed air leaks. These loud noises will often be the largest source of CFM loss, and you must find and repair them immediately.
Walking through your facility during a quiet time while the compressor is running is an excellent way to locate these pain points quickly. Immediately after a shift before powering the machine down is an ideal time to monitor your device. If you run your compressor all the time, find the quietest part of the day or take advantage of standard maintenance and temporary shutdowns. After locating the source of the leak noise, confirm the location by feeling for moving air.
Many times, compressed air leaks are very small, making them hard to detect by feeling or listening. Although these small leaks can create some sound, detecting them over other typical facility noises can be challenging. These small points are still important to identify and fix, especially if you have multiple leaks throughout the system. Larger facilities can have as many as 20 or 30 leaks or more, which can cause significant CFM loss over time.
You can often use specialized equipment, such as an ultrasonic leak detector, to find these small locations. These devices are non-invasive and offer an easy solution for detecting small leaks. The ultrasonic detector uses the high-frequency sound emitted by small leaks to pinpoint their location.
Pinprick leaks emit sound in a range of about 40 kHz, about twice the upper frequency detectable by humans. Ultrasonic detectors listen for noise in this range. As the operator moves around the facility, the detector will indicate whether they're getting closer to or farther from the leak by determining whether the sound is getting louder or softer. In this way, the detector leads the operator right to the source of the leak, much like the children’s game of “colder/warmer.”
Whether you opt to walk around your facility or use another device to detect leaks, there are several common locations you can check. The metal tubes can leak air at connection points. Evaluate cracked or rusty areas for possible leaks.
Air hoses are another common location for leaks. You'll find these hoses throughout the system and can use hand soap to detect tiny leaks if you're not using a detector. Unplug the system and use the soap and a small amount of water to cover the hoses. Turn on the system and watch for bubbles in the hoses, indicating a tiny leak. Also, check the connectors at the end of each hose. You'll hear a wheezing sound if the air is escaping from these components.
Common Causes of Compressed Air Leaks
You can find leaks anywhere in the system, but there are several locations you should monitor. Knowing the common causes of air leaks can help you prevent them in the future and identify them quickly to save resources.
For example, older piping often develops leaks at welds and joints over time. Additionally, you can find many leaks in what's known as the "dirty thirty," which is the last 30 feet of connectors, hoses and pipes that hook equipment into the air system.
Quick couplers are prone to leaking over time as the rubber seals begin to degrade. You can also often find leaks in split hoses, loose threaded joints and tube fittings. Monitoring these locations and understanding what causes leaks can help you save money and ensure your compressor receives the care it needs as quickly as possible.
Common causes of compressor air leaks include:
- Disconnects: Hoses, tubes and push-to-lock connection points are a common concern. If the connection point is worn out or isn’t correctly attached, it lets air escape. If any seals are missing O-rings, they likely have incorrect sealing.
- Missed welds: Pipes, metal tubing and flanges can cause leaks at their joints, especially with a gap in the welding.
- Worn materials: Packing at the cylinder rods, control valves and shut-off valves may become worn out over time. Repack them when they show signs of wear.
- Incorrect sealants: The wrong type of thread sealant or an improper application won’t guard against leaks. Use the right materials and follow their instructions.
- Incorrect filter installation: Filters, regulators and lubricators with a low initial cost can seem like great deals. However, these cheaply made components are more likely to leak. Choose quality filters and practice routine filter maintenance.
- Dirty seals: Seals with grime, dust and dirt won’t be air-tight.
- Increased pressure: The higher the pressure, the more air leakage you’ll experience through existing orifices.
- Old tools and equipment: You may lose air on the side of your pneumatic equipment. Disconnect and replace broken or leaky machines.
Should You Fix Compressed Air Leaks?
Often, it'll make sense to fix compressor air leaks. Repairing your machine can save money through less energy waste and prevent costs from needing to replace the unit. Additionally, keeping air leaks can worsen your device over time, making it essential to address the problem quickly. Your ROI can determine whether fixing air leaks is beneficial for your facility.
Consider these factors:
- How much the leak is costing you: You might be able to estimate how much an air compressor costs your facility by comparing the size of the leak and the resulting CFM loss. As a general rule, every CFM lost will cost your facility about $35 per hour of operation. You can use the worksheet above to estimate the total energy loss from system leaks and inefficiencies.
- How much the leak repairs will cost: You can sometimes repair air leaks for free under some energy company programs. Some leaks may require more costly repairs than your energy company will cover, depending on the leak's size or the repair's difficulty. A compressed air provider can detail whether your total will be higher than what your energy company will cover.
- Additional costs to consider: You must include potential costs associated with the repair. For example, you may need to shut down your production lines to address the problem, leading you to consider additional shutdown costs in the repair total.
You'll often find that large leaks are worth addressing. If you're unsure whether your leaks are a significant concern, you can request assistance from Fluid-Aire Dynamics. We can help you determine the calculations to establish whether leak repairs will benefit your facility.
Fixing Compressor Air Leaks
Poor maintenance is often the reason for most air leaks. Regularly replacing worn parts and tightening connections can prevent new leaks from springing up over time. Reducing the number of connection points can help prevent leaks, and you should always replace components that don't fit properly after you tighten them.
Note that you must decide which leaks are most important to repair. You won’t need to patch them all to reap significant cost savings. Mending 10 1/4-inch leaks will save you more money than 50 1/16-inch leaks. Repairing those 50 leaks will also net you more savings than 100 1/32-inch leaks.
When you begin fixing your leaks, start by replacing worn components, which could include:
- Tube and hose sections: You should isolate leaks to specific areas of the tubes and hoses and replace the parts that leak. Shorten the distance between the tools and compressor if possible.
- Valve seals and O-rings: Valves are particularly vulnerable to leaking. Replace O-rings and seals routinely. Heat and pressure cause these components to break down over time, so monitor and replace them frequently.
- Condensate drain: Your condensate traps will separate and collect water at peak efficiency when you clean them. As these components wear out, they can create leaks because they're adjacent to the compressor tank. Replace the drains and water trays regularly.
Although many worn parts and loose fittings can cause most leaks, the compressor tank can also present an issue. Leaks can cause gaps in the welding or spring rust in the tank, making it essential to address this issue quickly. Follow these steps to fix your compressor tank leak:
- Disconnect the hoses: Begin the process by detaching all tools and hoses from the compressor. Charge the device completely. Use an ultrasonic detector or the water and soap method from above to find individual leaks. You must replace the tank if you find leaks beyond the welding or along the seams.
- Tighten the fasteners: Pull the emergency release valve and allow air to escape and pressure to relieve for your safety. Tighten any loose fasteners and screws around the tank. If you notice worn components or those with rust, be sure to replace them.
- Check for ongoing leaks: Recharge the compressor and use an ultrasonic detector or the soap bubble method to check for leaks. Note the leaks on welded brackets and around seams by marking them.
- Grind down leaks: Release the pressure after powering down the machine. Find the leaks you detected and use an angle grinder around those areas. Flatten the raised metal at seams and welds until you expose the hole or crack and the space is flush with the rest of your tank.
- Seal the area: First, light a brazing torch and increase the oxygen until you have a bright blue flame. Heat the surface surrounding the hole. Next, press a brass brazing rod into the heated area and continue heating it with the flame until the material melts and pools along the surface. Continue until you reseal the ground-down area. Wait for the weld to dry and cool before recharging the compressor.
Professional will offer the best solution for repairing your components, connectors and the tank. Fluid-Aire Dynamics offers compressor system repairs and services to address leaks efficiently and safely. Our skilled technicians can help you reach maximum energy savings by using industry-approved techniques to address the most cost-draining leaks.
Preventing Compressor Air Leaks
As with most repairs, it saves time and costs less to prevent issues than to resolve them. Even when you’re prompt to repair leaks, servicing your system creates downtime. You can schedule preventive maintenance for convenient times to create less downtime than remedying problems after they occur.
By preventing leaks, your facility runs more efficiently all the time. Your tools get the pressure they need to function efficiently. Since you’ll have fewer leaks, you won’t have to play a constant game of catch-up. You’re also less likely to be caught off-guard by a major leak that shuts down a compressor and the equipment relying on it. With fewer leaks, you’ll save money on repair costs.
Prevent leaks through a combination of scheduled professional maintenance and employee training. Plan to check your facility for leaks about once a quarter. This is an excellent time to schedule regular maintenance and revisit previously patched leaks. When discovering new leaks, tag and repair them. Then, verify your system is running at improved efficiency due to the repairs.
On the training side, implement a reporting program so employees can notify you of leaks they discover. Teach them how to spot leaks and worn-out parts that may cause them. Your staff will be the first to notice when machines aren’t getting the correct air pressure. Incentivizing them to report potential leaks can help you get ahead of leak concerns. Your team should know how to secure air hose connections and take other steps to help prevent leaks.
Contact Fluid-Aire Dynamics to Repair Air Compressor Leaks
Fluid-Aire Dynamics provides sales and service for compressed air systems in San Antonio, Philadelphia, Detroit, Minneapolis, Milwaukee and Chicago. If you're experiencing air leaks, you can trust our highly experienced team to deliver the results you expect. We offer 24/7/365 emergency compressor repair so you can minimize downtime and boost productivity and efficiency.
Contact Fluid-Aire Dynamics for maintenance and service for your air compressor.
*Cubic Feet per Minute, the standard measurement of the velocity of air flowing through a system. The volume of air your air compressor is capable of producing in a given amount of time is usually measured in CFMs; a compressor rated for 50 CFMs produces 50 cubic feet of air every minute at max capacity.
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