Step 4 of the Six Steps to Optimizing your compressed air is to turn off your compressed air when it is not in use. This step can be done using two simple methods either by using manual controls such as ball valves or automated controllers such as solenoid valves. Manual controls are designed for long use and when switching on and off are infrequent. Ball Valves are one of the most commonly used manual shut offs for compressed air and other fluids.
Automated controllers allow your air flow to be tied into a system or process and turn on or off when conditions have been met. Solenoid valves are the most commonly used automated control device as they operate by using an electric current to open and close the valve mechanism within. Solenoid valves are some of the more versatile flow control devices due to the fact that they open and close almost instantaneously. Solenoid valves can be used as manual controls as well by wiring them to a switch or using simple programming on a PLC to turn the valve on or off using a button.
Some good examples of automated controllers are EXAIR’s Electronic Flow Controller (a.k.a. EFC) and EXAIR’s Thermostat controlled Cabinet Coolers.
The EFC system uses a photo eye to detect when an object is coming down the line and will turn on the air for a set amount of time of the users choosing. This can be used to control the airflow for all of EXAIR’s products. EXAIR’s Thermostat controlled Cabinet Coolers are used to control the internal temperature of a control cabinet or other enclosures. This is done by detecting the internal temperature of your cabinet and when it has exceeded a temperature which could damage electrical components it will open the valve until a safe temperature has been reached, then turn off.
By turning off your compressed air, whether it be with manual or automated controllers, a company can minimize wasted compressed air and extend the longevity of the air compressor that is used to supply the plants air. The longevity of the air compressor is increased due to reduced run time since it does not need to keep up with the constant use of compressed air. Other benefits include less use of compressed air and recouped cost of compressed air.
If you have questions about our compressed air control valves or any of the 16 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.
Cody Biehle Application Engineer EXAIR Corporation Visit us on the Web Follow me on Twitter Like us on Facebook
A food manufacturing company was looking for a more efficient way to dry polypropylene trays that were filled with food product. With their current operation, they would send already packed and sealed food trays through a washing system that used sterilized water. The trays would then have to be dried prior to bulk packaging. The operators would place the trays side by side on a 24” wide open-mesh stainless steel metal conveyor with two or three trays at a time (depending on the tray dimensions). They contacted EXAIR because they wanted to replace their “old and inefficient system” with something better.
In my discussions, they gave some additional details of the operation and the problems that they were seeing. The dimensions of the trays ranged from 150 to 200mm long by 100 to 150mm wide by 35 to 50mm in height. They were cleaning at a rate of 30 trays per minute through the washing and drying system. The washer was designed to recycle the water to improve “green” operations. But the trays were carrying much of the water outside the machine. Thus, they would have to stop and refill the wash system with fresh water.
After the washing cycle, the drying section began. It consisted of two parts; a sponge roller and a heated chamber that would blow hot air. First the trays would run under the sponge roller to absorb the water from the top of the trays. A feature that they did not like was the continuous adjustment to the sponge roller for the different tray heights. They had to make sure that they had good contact without stopping the movement.
Also, with bulk of the water being on top of the trays, the sponge surface would get saturated. They would have to stop the process to change with a dry foam pad or replace due to wear. After the sponge roller, it would move into a heated chamber to remove the remaining portion of the water from the trays. They used a 11 KW heating system to blow hot air. This part of their system required a lot of electricity to run. They wondered if EXAIR could help streamline their process and reduce energy costs.
They sent a photo of their system, reference above. As described, the trays were moving intermittently through the wash cycle and then into the drying operation. When gaps are present in a process, the Electronic Flow Control, or EFC, becomes a great product for energy efficiency. It is designed to use a photoelectric sensor to detect a part and initiate a timing sequence. Using a solenoid valve, it will turn on the compressed air only when needed. With the drying operation, I suggested that they could remove the sponge roller and heated chamber, and replace them with two Super Air Knives. In conjunction with the EFC, we can decrease energy usage, reduce downtime, and increase savings. Profit margins can be critical in the food industry, and EXAIR has many ways to help.
To expand a bit more about revitalizing the “old and inefficient system” with EXAIR products, I made some suggestions. I recommended two Stainless Steel Super Air Knife Kits, model 110224SS, to be placed near the end of the conveyor. One Super Air Knife would be positioned above the tray to blow across the top; and one would be positioned below the tray under the mesh conveyor to blow across the bottom.
At a slight blowing angle in a counter-flow direction, the air streams would remove the water from the top and bottom of the tray at the same time. This would create a non-contact “wiping” solution. Now they do not have to worry about parts wearing out due to contact. Another unique feature of the Super Air Knife is the strength of the laminar air stream. It is consistent from 3” (76mm) to 12” (305mm) away from the target. Thus, they can easily set the height of the Super Air Knives to dry all the different trays without adjusting it.
And as an added benefit, the water that was being blown off the trays by the Super Air Knives remained within the washing system. The sterilized water was not being wasted and could be recycled. With the Electronic Flow Control, I recommended the model 9056. It is a user-friendly device with eight different timing sequences. They were able to position the photoelectric sensor near the outlet of the washing system. As soon as the trays were detected, the Super Air Knives would turn on to blow two or three trays at the same time. With the EXAIR products installed, the system went from using 11 KW down to 4 KW, a 63% savings.
EXAIR has helped many customers like this one above. When it comes to energy savings, EXAIR leads the way. With two Super Air Knives and an EFC, we were able to modernized their system; save on water, improve productivity, reduce the overall footprint, and save on their energy usage. If you have a similar application, you can contact an Application Engineer at EXAIR. We will be happy to update your system.
If you’re a follower of the EXAIR Blog, you’re probably well aware that compressed air is the most expensive utility in an industrial environment. The average cost to generate 1000 Standard Cubic Feet of compressed air is $0.25. If you’re familiar with how much air you use on a daily basis, you’ll understand just how quickly that adds up.
To make matters worse, many compressed air systems waste significant amounts of compressed air just through leaks. According to the Compressed Air Challenge, a typical plant that has not been well maintained will likely have a leak rate of approximately 20%!! Good luck explaining to your finance department that you’re carelessly wasting 20% of the most expensive utility.
The best way to save energy associated with the costs of generating compressed air is pretty straightforward and simple: TURN IT OFF! Placing valves throughout your distribution system allows you to isolate areas of the facility that may not need a supply of compressed air continuously.
Even a well-maintained system is going to have a leakage rate around 10%, it’s darn near impossible to absolutely eliminate ALL leaks. By having a valve that allows you to shut off the compressed air supply to isolated areas, you’re able to cut down on the potential places for leaks to occur.
You’re likely not running each and every machine continuously all day long, if that’s the case why not shut off the air supply to those that aren’t running? When operators go to lunch or take a break, have them turn off the valves to prevent any wasted air. The fact of the matter is that taking this one simple step can truly represent significant savings when done diligently.
You wouldn’t leave your house with all the lights and TV on, so why leave your compressed air system running when it’s not in use? Even if everyone’s left for the day, leaks in the system will cause the compressor to keep running to maintain system pressure.
Taking things one step further, EXAIR’s Electronic Flow Control (EFC) utilizes a solenoid controlled by photoelectric sensor that has the ability to shut off the compressed air when no part is present. If you’re blowing off parts that are traveling along a conveyor with space in between them, there’s no need to continuously blow air in between those parts. The EFC is able to be programmed to truly maximize your compressed air savings. The EFC is available in a wide range of different capacities, with models from 40-350 SCFM available from stock and systems controlling two solenoid valves for larger flowrates available as well.
It’s no different than turning off your house lights when you leave for work each day. Don’t get caught thinking compressed air is inexpensive “because air is free”. The costs to generate compressed air are no joke. Let’s all do our part to reduce energy consumption by shutting off compressed air when it isn’t necessary!
Two basic methods to set up a compressed air operation for turning off is the ball valve and the solenoid valve. Of the two, the simplest is the ball valve. It is a quarter turn, manually operated valve that stops the flow of the compressed air when the handle is rotated 90°. It is best for operations where the compressed air is needed for a long duration, and shut off is infrequent, such as at the end of the shift.
The solenoid valve offers more flexibility. A solenoid valve is an electro-mechanical valve that uses electric current to produce a magnetic field which moves a mechanism to control the flow of air. A solenoid can be wired to simple push button station, for turning the air flow on and off – similar to the manual valve in that relies on a person to remember to turn the air off when not needed.
Another way to use a solenoid valve is to wire it in conjunction with a PLC or machine control system. Through simple programming, the solenoid can be set to turn on/off whenever certain parameters are met. An example would be to energize the solenoid to supply an air knife when a conveyor is running to blow off parts when they pass under. When the conveyor is stopped, the solenoid would close and the air would stop blowing.
The EXAIR EFC (Electronic Flow Control) is a stand alone solenoid control system. The EFC combines a photoelectric sensor with a timer control that turns the air on and off based on the presence (or lack of presence) of an object in front of the sensor. There are 8 programmable on/off modes for different process requirements. The use of the EFC provides the highest level of compressed air usage control. The air is turned on only when an object is present and turned off when the object has passed by.
By turning off the air when not needed, whether by a manual ball valve, a solenoid valve integrated into the PLC machine control or the EXAIR EFC, compressed air usage will be minimized and operation costs reduced.
If you have questions about the EFC, solenoid valves, ball valves or any of the 15 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.
A few months ago, I took a phone call from a manufacturing engineer who worked at a large candy production facility here in the United States. Extra chocolate was dripping out of the candy molds onto the conveyor belt below. Within a few hours the belt was dirty enough they would have to stop the line and clean the residual chocolate off the belt.
The best solution I found was a 72” 316 Stainless Steel Super Air Knife. It worked great when powered at 60 psig inlet pressure. The laminar flow of the Super Air Knife was perfectly suited for this application. The knife was mounted between the mold and the belt to help solidify and blowoff the excess drips of chocolate. There was one drawback, the Super Air Knife was not needed to blow the belt continuously and the continuous demand was not desirable during peak production.
The simple solution for this was the EXAIRElectronic Flow Control, the EFC minimizes compressed air use by turning off the air when a sensor is triggered. Since there was a 4.5-minute time gap between each mold set this was a great solution. When the photoelectric eye saw a mold, it then told the solenoid valve to open and supply the knife with compressed air for 30 seconds while the mold was open and the excess chocolate would be dripping. See the Savings calculations below;
165.6 SCFM x 60 minutes x $ 0.25 / 1000 SCFM = $ 2.48 per hour
$ 2.48 per hour x 8 hours = $ 19.84 per 8-hour day
$ 19.84 x 5 days = $ 99.20 per work week
$ 99.20 per week x 52 weeks =$5,158.40 per work year without the EFC control
With the EFC installed (turning the compressed air off for 4 minutes 30 seconds with a 30 second on time = 6 minutes/hour compressed air usage)
165.6 SCFM x 6 minute x $ 0.25 / 1000 SCFM = $ 0.25 per hour
$ 0.25 per hour x 8 hours = $ 2.00 per 8-hour day
$ 2.00 x 5 days = $ 10.00 per work week
$ 10.00 per week x 52 weeks = $520.00 per work year with the EFC control
$ 5,158.40 per year (w/o EFC) – $ 520.00 per year (w/ EFC) = $4,638.40 projected savings per year by incorporating the EFC.
This example illustrates, clearly, why choosing the EFC is a good idea. It has the ability to keep compressed air costs to a minimum and saves compressed air for use within other processes around the plant. With this type of compressed air savings, the unit would pay for itself in less than 3 months.
A few weeks ago, we posted a blog discussing how artificial demand and leaks can lead to poor performance and expensive waste. Today, I’d like to review how following a few simple steps can help optimize your current compressed air system and reduce compressed air usage.
The first step you want to consider is measuring the air usage in the system. To do this, you want to start at the compressor and check individual leads to each drop point to a blowoff device, record your findings to track the demand. By measuring your compressed air usage, you can locate the source of high usage areas and monitor the usage on each leg of the system. If the demand exceeds the supply, there is potential for problems to arise, such as lowered pressure and force from compressed air operated devices leading to irregular performance.
EXAIR’s Digital Flowmeters are designed to measure flow continuously and accurately to give you real-time flow measurements of your compressed air system to help identify problems areas.
Step 2 is to locate the source of waste. Again, compressed air leaks can result in a waste of up to 30% of a facility’s compressor output. A compressed air leak detection and repair program can save a facility this wasted air. Implementing such a program can be used as a way for a facility to “find” additional air compressor capacity for new projects. Whenever a leak occurs, it will generate an ultrasonic noise.
Our Ultrasonic Leak Detector is designed to locate the source of ultrasonic sound emissions up to 20’ away. These ultrasonic sound emissions are converted to a range that can be heard by humans. The sound is 32 times lower in frequency than the sound being received, making the inaudible leaks, audible through the included headphones and the LED display gives a visual representation of the leak.
The 3rd step involves finding the source of noisy and wasteful blowoffs, like open pipes or homemade blowoffs, and replacing them with an energy efficient, engineered solution. By replacing these devices, you are not only reducing the amount of waste but also improving operator safety by complying with OSHA safety requirements.
EXAIR’s Digital Sound Level Meter is an easy to use instrument that measures and monitors the sound level pressure in a wide variety of industrial environments. The source of loud noises can be quickly identified so that corrective measures can be taken to keep sound levels at or below OSHA maximum allowable exposure limits.
The easiest way to reduce compressed air usage and save on operating expense is to turn off the compressed air to a device when it isn’t needed, step 4 in the process. Not only will this save money, in many cases, it can also simplify a process for the operator.
A simple manual ball valve and a responsible operator can provide savings at every opportunity to shut down the air flow.
For automated solutions, a solenoid valve can be operated from a machine’s control. For example, if the machine is off, or a conveyor has stopped – close the solenoid valve and save the air.
A foot pedal valve offers a hands free solution to activate an air operated device only when needed, such as being implemented in an operator’s work station.
For even more control, you can use a device like our EFC or Electronic Flow Control. This helps minimize compressed air usage by incorporating a programmable timing controlled (0.10 seconds to 120 hours) photoelectric sensor to turn off the compressed air supply when there are no parts present. It is suited for NEMA 4 environments and can be easily wired for 100-240VAC.
Step 5, intermediate storage. Some applications require an intermittent demand for a high volume of compressed air. By installing a receiver tank near the point of high demand, there is an additional supply of compressed air available for a short duration. This will help eliminate fluctuations in pressure and volume.
EXAIR offers a 60 gallon, ASME approved vertical steel tank with mounting feet for easy installation near high demand processes.
Many pneumatic product manufacturers have a certain set of specifications regarding performance at stated input pressures. In many applications, or in the case of using a homemade blowoff device like open pipe, these wouldn’t necessarily require the full rated performance of the device or full line pressure. Controlling the air pressure at the point-of-use device will help to minimize air consumption and waste, step 6.
By simply installing a pressure regulator on the supply side, you can start off at a low pressure setting and increase the pressure until the desired result is achieved. Not only will this help to conserve energy by only using the amount of air required for the application, it also allows you to fine tune the performance of the point-of-use device to match the application requirements.
If you have any questions, please contact an application engineer at 800-903-9247.
Compressed air is the most expensive utility for most industrial facilities. The energy costs associated with the generation of compressed air can be very high. Because of this, EXAIR manufactures a wide range of products geared towards reducing your overall compressed air consumption.
The best way to save compressed air is to simply turn it off when it’s not being used. This might seem pretty simple, but there may be processes in your facility where this couldn’t be achieved by just turning a valve. In applications where product is traveling along a conveyor, and must be dried, cooled, or blown off, there is likely some spacing in between the parts. It isn’t necessary to keep the blowoff running constantly if there’s periods of intermittent spacing. To help reduce the overall load on the air compressor, implementing a solution to shut the air off in between each part can have a dramatic impact. EXAIR’s Electronic Flow Control, or EFC, is designed to improve efficiency by reducing overall compressed air usage. It utilizes a photoelectric sensor that detects when the part is present. When it’s not, it triggers a solenoid valve to close and shut off the compressed air supply.
Let’s take a look at an example that shows just how much air (and $$) an EFC can save. We had a manufacturer of car bumpers that was using a Model 112060 60” Super Ion Air Knife supplied at 40 PSIG to remove dust prior to a painting operation. The bumpers were moving at about 10’/minute and had 1’ of spacing in between each part. The bumpers are only under the blowoff for 10 seconds, while 6 seconds passed with no part present. With a (3) shift operation, this translates to 1,440 minutes of nonstop compressed air usage per day.
A 60” Super Ion Air Knife will consume 102 scfm at 40 PSIG. Their current method was using a total of 146,880 SCFM.
102 SCFM x 1,440 minutes = 146,880 SCF
With the EFC installed, the air was shut off for 6 seconds reducing the airflow by 37.5%. With the EFC installed, the compressed air consumption per day was reduced to 91,800 SCF.
146,880 SCF x .625 = 91,800 SCF
As a general rule of thumb, compressed air costs $0.25/1,000 SCF. By saving 55,080 SCF per day, this manufacturer was able to save $13.77 per day. Since this was a 24 hour/day shift running 7 day/week, total savings for the year came in at $5,012.28. This easily recoups the costs of the EFC and then begins to pay you in less than 6 months.
55,080 SCF x ($0.25/1,000 SCF) = $13.77
$13.77 x 7 days/week x 52 weeks/year = $5,012.28
The EFC models available from stock can accommodate flows up to 350 SCFM. For applications requiring more compressed air, EFCs with dual solenoids are also available. If you have an application in one or more of your processes where intermittent compressed air use could help save you money, give us a call. We’d be happy to take a look at the application and help determine just how quickly the EFC could start paying YOU!