A major benefit to utilizing compressed air is the speed at which it can be shut off and re-energized for use – in fact, this can be done instantaneously. Shutting down the supply of compressed air to an application while it is not needed can drastically reduce the compressed air consumption of the process. This is an easy remedy that can produce significant savings.
Think about a place where you have a compressed air blow off with spaces between the parts or dwell times in conveyor travel. What about break times, do operators continue to keep the air on when they leave for a break or even worse, for the day?
Step number four in EXAIR’s Six Steps to Optimization is:
A simple manual ball valve and a responsible operator can provide savings at every opportunity to shut down the airflow. But an automated solution is a no-brainer and can provide significant savings.
For a more automated approach, you can add a solenoid valve that would tie into your existing PLC or e-stop circuit, into your compressed air supply lines to aid in turning the compressed air on and off.
For an automated on/off solution can be found by using the EXAIR EFC (Electronic Flow Control). The EFC is made to accept 110V or 220V AC, and convert it to 24V DC to operate a sensor, timer, and solenoid valve. Its multiple operating modes allow you delay on, delay-off, and delay on/off among others. The operating mode can then be set to the specific time necessary for a successful application.
The spaces between parts can be turned into money saved. Every time you reach the end of a batch run, the EFC can turn the air off. You can also add solenoid valves and run them from your machine controls. If the machine is off, or the conveyor has stopped – close the solenoid valve and save the air. The modes are all defined in the video below.
So, take a look, or even better a listen, around the plant and see what you can find that could benefit from turning the air off; even if it is just for a moment it will help put money back into your bottom line.
Knowing your compressed air needs and understanding the limitations of your equipment is essential when optimizing your compressed air system. Everything about compressed air systems are interrelated. Items putting demand on your system can and will effect how the equipment supplying the demand will operate. Taking a holistic approach when optimizing your compressed air system will not only give you a better understanding of your supply and demand requirements but will also serve as the most efficient means to optimize your process. Now lets look at the six steps to optimizing.
Measure: the air consumption You must create a baseline to understand your demand requirements. How can you measure your improvements if you do not understand your total demand or baseline? Installing an EXAIR Flow Meter to your main air lines will help identify the amount of compressed air demand you have and help identify areas of concern.
Find and fix leaks in the system: The repair of compressed air leaks is one of easiest ways to gain energy savings. In most cases all you need is a keen sense of hearing to locate a leak. Once a you have confirmed a leak then the make the necessary repairs. Harder to find leaks may require tools such as EXAIR’s Ultrasonic Leak Detector. This is a hand held high quality instrument that can be used to locate costly air leaks.
Upgrade your blow off, cooling and drying operations: Updating your compressed air process tooling can save you energy and help you comply with OSHA noise and safety regulations. An example would be to replace old blow off or open pipe systems with EXAIR Safety Air Nozzles. Replacing open copper tubes or pipes can amount up to 80% air savings. You achieve lower sound levels and significant energy savings.
Turn off the compressed air when it isn’t in use: It sounds obvious but how many times has an operator left for a break or lunch and doesn’t shut off the compressed air for his/her station? The minutes add up to a significant amount of time annually meaning there is opportunity for energy savings. The use of solenoid valves will help but EXAIR’s Electronic Flow Control (EFC) will dramatically reduce compressed air costs with the use of a photoelectric sensor and timing control.
Use intermediate storage of compressed air near the point of use: The use of storage receivers can improve your overall system efficiency in a number of ways. For example, using a main air receiver at the compressor room can make load/unload compressor control more efficient. Localizing receiver tanks such as EXAIR’s 9500-60 sixty gallon receiver tank by the point of use for a high demand process will stabilize the demand fluctuations allowing a more fluid operation.
Control the air pressure at the point of use to minimize air consumption: The use of pressure regulators will resolve this issue. Using regulators you can control the amount of air being processed at each point of use. EXAIR offers different sized pressure regulators depending upon your air line and process requirements. Regulating the compressed air to the minimum amount required and will reduce your overall demand resulting in annual savings and a payback schedule.
Compressed air optimization can definitely be implemented using low cost and manual procedures but sometimes you will need a higher level means to achieve your goal. EXAIR has many optimization products to support your efforts. You can review our catalog, blogs and videos at www.EXAIR.com or by calling 800.903.9247 and any of our qualified Application Engineers will assist you.
Compressed air is expensive, and you should treat it that way. Frequent readers of the EXAIR Blog are familiar with our Six Steps to Compressed Air Optimization, and you may have seen these recent installments on Steps 1 and 2:
Now, there isn’t a strict order in which you MUST perform these steps, and they’re not all applicable in every air system (looking at you, Step 5: Use Intermediate Storage,) but these are likely the steps that a certified auditor will take, and the order in which they’ll take them. If you’re looking for immediate, quantifiable results, though, Step 3 is a great place to start. Consider:
A 1/4″ copper tube blow off can consume as much as 33 SCFM when supplied with compressed air at 80psig. It’ll give you a good, strong blow off, for sure. You can crimp the end and get that down to, say, 20 SCFM or so. Or, you can install a Model 1100 Super Air Nozzle with a compression fitting, and drop that to just 14 SCFM.
If you’re tracking your compressed air usage, you’ll see that replacing just one of them saves you 45,600 Standard Cubic Feet worth of compressed in one 5 day (8 hour a day) work week. That’s $11.40 in air generation cost savings, for a $42 (2020 List Price) investment.
If you spend time in the space where it’s installed, you’ll notice a dramatic improvement in the noise situation. That sound level from the copper tube is likely over 100 dBA; the Super Air Nozzle’s is only 74 dBA.
Drilled pipes are another common method to create a blow off. They’re easy & cheap, but loud & expensive to operate.
A pipe drilled with 1/8″ holes and supplied @80psig will consume 13 SCFM per hole, and the holes are typically drilled on 1/2″ centers.
An EXAIR Super Air Knife consumes only 2.9 SCFM per inch of length, and because it’s an engineered product, it’s a LOT quieter as well. Drilled pipes are, essentially, open ended blow offs just like the copper tube mentioned above. When you let compressed air out of a hole like that, all the potential energy of the pressure is converted to force…and noise.
Drilled pipes are among the worst offenders; almost always well in excess of 100 dBA. Super Air Knives generate a sound level of only 69 dBA with 80psig compressed air supply. They are, in fact, the quietest compressed air blowing product on the market today.
These aren’t just theoretical “for instances” either – the data, and the photos above, come from actual Case Studies we’ve performed with real live users of our products. You can find them here, and here (registration required.)
Since air compressors use a lot of electricity to make compressed air, it is important to use the compressed air as efficiently as possible. The compressed air system is considered to be the “forth” utility behind gas, water, and electricity. It is necessary for pneumatic systems, but it is the least efficient of the utilities. For every $1.00 that is put into making compressed air, you only get roughly 5¢ of work from it. EXAIR has six simple steps to optimize your compressed air system. Following these steps will help you to cut electrical costs, reduce overhead, and improve your bottom line. In this blog, I will cover the second step – find and fix leaks.
One of the largest problems affecting compressed air systems is leaks. That quiet little hissing sound from the pipe lines is costing your company much money. A study was conducted by a university to determine the percentage of air leaks in a typical manufacturing plant. In a poorly maintained system, they found on average that 30% of the compressor capacity is lost through air leaks. For a 100 hp compressor, you are losing 30 hp into the ambient air. To put a dollar value on it, a leak that you cannot physically hear can cost you as much as $130/year. That is just for one inaudible leak in hundreds of feet of compressed air lines. For the leaks that you can hear, you can tell by the chart below (**Note 1) the amount of money that can be wasted by the size of the hole. Unlike a hydraulic system, compressed air is clean; so, leaks will not appear at the source. You have to locate them by some other means.
Most leaks occur where you have threaded fittings, connections, hoses, and pneumatic components like valves, regulators, and drains. The Optimization product line from EXAIR are designed to help improve your compressed air system, and the most effective way is to eliminate leaks. The Ultrasonic Leak Detectors can find the air leaks, and the Digital Flowmeters can monitor your system for air leaks. With both of these products included in your leak preventative program, you will be able to keep your compressed air system running optimally and reduce the “hidden” cost of leaks.
When a leak occurs, it emits an ultrasonic noise caused by turbulence from the gas escaping. This ultrasonic noise can be at a frequency above the audible level for human hearing. The EXAIR Ultrasonic Leak Detector can pick up these frequencies and make the leaks audible. With three sensitivity ranges and LED display, you can find very minute leaks. It comes with two attachments; the parabola to locate leaks up to 20 feet away, and the tube attachment to define the exact location in the pipe line. Once you find a leak, it can be marked for fixing.
With the Digital Flowmeters, you can continuously monitor for waste. Air leaks can occur at any time within any section of your pneumatic area. You can do systematic checks by isolating sections with the Digital Flowmeter and watch for a flow reading. Another way to monitor your system would be to compare the results over time. With the Digital Flowmeters, we have a couple of options for recording the air flow data. We have the USB Datalogger for setting certain time increments to record the air flows. Once the information is recorded, you can connect the USB to your computer, and with the downloadable software, you can view the information and export it into an Excel spread sheet. We also offer a wireless capability option with the Digital Flowmeters. You can have multiple flow meters that can communicate with your computer to continuously log and record the flow information. Once the flow information starts trending upward for the same process, then you can use the Ultrasonic Leak Detector to find the leak. It can also give you a preventative measure if a pneumatic system is starting to fail.
Compressed air leaks will rob you in performance, compressor life, and electrical cost. It is important to have a leak preventative program to check for leaks periodically as they can happen at any time. The EXAIR Ultrasonic Leak Detector and the Digital Flowmeters will help you accomplish this and optimize your compressed air system. Once you find and fix all your leaks, you can then focus on improving the efficiency of your blow-off devices with EXAIR products and save yourself even more money.