In my last blog, I went over How to Choose/Build an E-Vac system, and you can read about that here– The E-Vac’s are a compressed air powered, single stage vacuum generator, providing a low cost solution for creating a vacuum for many applications. Today, we will look at the many accessories that are available to complete a vacuum system best suited to your vacuum application.
For pick and place operations and hold down or clamping processes, we offer an array of Vacuum Cups. Available from stock are small and large Round, Oval, and Bellows styles. Round cups are best suited for smooth, flat surfaces. Oval cups provide the most vacuum due to the larger surface area, making them ideal for lifting heavy loads. The Bellows style is best suited for textured or uneven surfaces, where the folds provide a collapsible area that allows the cup to compress and seal to the uneven surface.
Small and Large Round, Oval and Bellows Vacuum Cups
For vacuum processes where personnel are nearby, there are two (2) types of mufflers available to reduce the sound level to comply with the limits OSHA Standard 29 CFR – 1910.95(a) has established. The EXAIR E-Vac Mufflers are designed so that the E-Vac exhaust is not impeded, so that the highest and fastest vacuum response is achieved. The Standard Muffler (for use with In-Line E-Vacs only) has a closed end and is best suited for vacuum draws that are free from dust and debris. The Straight Through Muffler is open all the way through and is recommended for those vacuum draws where there will be dirt and debris, since it will not plug up. The Straight Through style offers the best sound level reduction, up to 26 dBA.
Standard and Straight Through Mufflers
The vacuum port of the E-Vacs has an NPT threaded connection and with a suitable connector, a vacuum cup can be closely installed, minimizing the system air volume. When vacuum cups are to be remotely mounted, Push-In Connector Type Fittings of assorted styles are available along with the polyurethane tubing to make the installation and vacuum plumbing a cinch.
Push-In , Swivel Elbow, Swivel Branch Tee, and Bulkhead Connectors
And finally, to get the best performance and maintenance free operation from your E-Vac, always use a source of clean, dry compressed air. We can help you do that with a wide array of Automatic Drain Filter Separators and Oil Removal Filters sized to pair up with the various E-Vac’s. Also available are Pressure Regulators, Vacuum Gauges, Manual Shut Off Valves, Solenoid Valves, and Compressed Air Hose.
If you have questions about E-Vacs and accessories 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.
EXAIR’s compressed air powered E-Vac single stage vacuum generators are a low cost way create vacuum for many operations including- pick and place, clamping, chucking, alignment, lifting, and many others.
The E-Vac provide instantaneous response and are commonly used for pick and place operations.
EXAIR offers the In-Line and Adjustable style of E-Vacs. Both are compact and easy to mount at point of use. With 18 total models available, there is sure to be one that meets any application.
An E-Vac in Robotic Lift Operation
How to Build An E-Vac System:
Step 1 – Select E-Vac type:
A – Determine if the part to be lifted is porous (Example, cardboard) or non-porous (Example, plastic sheet)
Porous materials require a low vacuum generator which produces a lower vacuum in exchange for higher vacuum flow which is capable of maintaining a good vacuum level through material that aloows air to flow through itself.
Non-Porous materials are best suited to use the high vacuum generator which is capable of producing more powerful vacuum for the application.
B – Select a style of E-Vac – In-Line Low Vacuum, In-Line High Vacuum, or Adjustable
Non-Porous – high vacuum generator, max vacuum = 27″ Hg (91 kPa)
Adjustable – max vacuum = 25″ Hg (85 kPa)
Step 2 – Find the weight of the part to be lifted:
Step 3 – Multiply the weight by a vacuum cup safety factor (2 for a horizontal vacuum cup position, and 4 for a sideways vacuum cup position)
Step 4 – Determine the number of cups needed, considering the following:
A – How many cups are needed to evenly distribute the weight for stable lifting and placement.
B – What is the weight that each vacuum cup can lift based on maximum vacuum available?
C – Select the appropriate vacuum cup from the different styles available.
Step 5 – Choose the E-Vac model, considering the entire vacuum system from the E-vac to the part:
A – Number of vacuum cups per E-Vac.
B – Length and size of the vacuum tubing.
C – Vacuum cup size and type.
The volume of air to evacuate from your vacuum system and the vacuum flow of the E-Vac selected will determine the time it takes to build the lifting vacuum level.
A lower volume of air in the system and/or higher capacity (SCFM/SLPM) E-Vac will result in faster pick-up times.
It is difficult to calculate an exact pick-up time.
Example – Sheet of material 3′ x 3′ (0.91m x 0.91 m) that weighs 25 lbs. (11.3 kg). Each sheet is in stack and will be placed on a conveyor.
As you can see, there is a lot to consider when building an E-Vac system. Feel free to contact us and we can help go through the steps.
If you have questions about E-Vacs 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.
When it comes to vacuum systems, EXAIR manufactures a very compact and reliable product line called the E-Vac Vacuum Generators. As a simple vacuum pump, you only need to connect to a compressed air source. It uses a venturi design to generate high vacuum levels very efficiently. Since they do not require motors, they are low cost with a wide range of vacuum flows and pressures. EXAIR offers three different types, the High Vacuum Generators for non-porous objects, the Low Vacuum Generators for porous objects, and the Adjustable E-Vac Vacuum Generators. In this blog, I will cover the Adjustable E-Vac Vacuum Generators and the variety of suction cups that we provide.
The Adjustable E-Vac gives flexibility to your vacuum system to change the vacuum levels. The simplicity in the design makes it a great tool for lifting, clamping, chucking, and pick-and-place. The design also allows for adjustability. By loosening a lock nut, you can turn the body to reach different vacuum levels. So, they can be used to move both porous and non-porous materials. We offer four different sizes with vacuum flows ranging from 5.8 SCFM (164.2 SLPM) to 81 SCFM (2293.6 SLPM). With the Adjustable E-Vac, you can change the vacuum pressure to go as high as 25” Hg (85 KPa). Ideal for dialing in the correct vacuum for delicate materials or controlled clamping.
Adjustable E-Vac: How it works
The Adjustable E-Vacs can be packaged in a variety of ways. The kits help to experiment with different vacuum cups to help determine the best fit for your application. EXAIR offers two types of kits, the standard kit and the deluxe kit. The Adjustable E-Vac Kit would include the E-Vac, an assortment of four vacuum cups that are matched to the performance of the Adjustable E-Vac, an assortment of vacuum fittings and 10 feet (3 meters) of vacuum tubing. The Adjustable E-Vac Deluxe Kit has the items in the standard kit above plus an Automatic Drain Filter and Pressure Regulator with gage. With both individual units and kits, you can add a muffler to help reduce the noise even more by adding an “M” to the end of the model number.
EXAIR also offers a variety of suction cups to attach to a variety of objects. We have the small round, the large round, the oval, and the bellows suction cups. With the different designs, you can pick up a wide range of materials, both porous and non-porous items. The vinyl material resists wear and distortion for many repetitive cycles. Here is a better description of each cup below:
Round Cups
Round: EXAIR has a small and large round style. This gives us a range of surface areas that we can target to help maximize lift. They can come either with cleats for heavier lifting and stability or without cleats. They work great with flat smooth surfaces for horizontal and vertical lifting.
Oval Cup
Oval: The vacuum is defined by a skinny long area. EXAIR offers four different sizes. If you have tight spaces or selectable targets like opening a bag at the top, then the oval shape will work. They can also handle flat rigid sheets like wood, glass, cardboard, and composites.
Bellows Cup
Bellows: These suction cups are best suited for uneven or contoured surfaces. The convolutions around the diameter allow for the cup to collapse and “wrap” around uneven surfaces. The internal volume is larger than the other cups, so the release and attach times will be extended. But, for odd surface formations, they can come in very handy.
To combine the Adjustable E-Vac with the Vacuum Cups, how can we determine which ones to use in your application? Here is some information that we will have to know before getting started. I like to use anagrams for memory recall, and here is a list that I like to call MOST:
Material
Orientation
Size/weight
Time
Material will tell us if the object is porous or non-porous. Porous objects are items like cardboard, fabric, cement, etc. The material can have a rough surface or pores that will allow air to pass through or around the cup. The Adjustable E-Vac can have the vacuum pressure altered to pick up the material without damaging the surface. Non-porous objects are items like glass, metal sheets, and plastic. They have a smooth texture on the surface. These materials should use the highest vacuum pressure of 25” Hg (85 KPa) to hold the most weight.
Orientation will help us to calculate a safety factor. EXAIR’s motto has always been safety. This is important because we want to make sure that the object is secure during movement. We just need to know if the object is being picked up horizontally only, or if the object is being picked up vertically or rotated in a vertical position. Then we can apply a safety factor to handle the weight in any orientation.
Size/Weight is simple. The size is the area that we can pick up the object. In some instances, we may only have a small target area while in other applications, we will have an entire sheet. The type of Vacuum Cups is selected by this target area. The weight will determine the number of Vacuum Cups and Adjustable E-Vacs required to pick up large objects safely.
Time is for applications with cycle rates. If the job requires a set time to support and release in a known time frame, then we can determine the correct Adjustable E-Vac This can be used for leak checking, clamping, and automatic packaging.
The Adjustable E-Vac Generators are simple, flexible, and very reliable. As a vacuum pump, they are very compact because they do not use any motors which can wear out. If you contact an Application Engineer at EXAIR with MOST, we will be able to get the most from your vacuum system.
Over the last 3 months, I have been in contact with a customer, keeping track of an application that involved the EXAIRE-Vac. The customer had reached out to us looking for some advice on how to solve a process problem. The operation is a drawing/stamping process, and the when the part exits the machine there is coolant that resides in a deep draw section, approx 0.4″ in diameter by 3.5″deep. About 1 oz of coolant per part is retained, and over many 1000’s of parts, would add up to lost dollars and messy clean up.
The customer was looking for an automated process that would be able to draw out the coolant and direct the liquid back to the coolant reservoir, all while maintaining the current machine run rate. We settled in on the model 840015 Adjustable E-Vac Generator. The Adjustable E-Vac has a straight through pathway from suction through to discharge, allowing for fast evacuation times. A simple turn of the unit changes the vacuum and flow levels to best match the needs of the application. The Adjustable E-Vac coupled to a solenoid valve controlled by the stamping machine resulted in the automatic system the customer was looking for.
Adjustable E-Vac Family
The customer ordered a unit, and based on the preliminary bench testing, it was approved for a production run trial. After some tweaking in the production environment, the unit was performing to spec, and was then subjected to a 100,000+ part run. The results were a success! Instead of the parts exiting onto an inclined conveyor, relying on gravity to drain and causing coolant to collect under the conveyor, the coolant could be removed in a controlled manner and sent back to the reservoir. Less mess and no coolant loss.
EXAIR manufactures (3) types of E-Vacs – Low vacuum generators for porous materials, high vacuum generators for non-porous materials, and the adjustable type for flexible vacuum performance. They are available in multiple sizes, to best match the vacuum requirements, while using the least amount of compressed air.
To discuss your application and how the EXAIR E-VAC can benefit your process, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.
