Tag: check valves

E-Vac Generators, Cups and Accessories

Published on by EricKuhnash@EXAIR.comLeave a comment

When it comes to our E-Vac vacuum generators and creating a successful design for you application EXAIR has the fundamentals. EXAIR’s compressed air powered E-Vacs are designed primarily for pick and place operations but also have other uses such as evacuating liquids and gasses from containers and holding workpieces in place. E-Vacs come in different sizes including an Adjustable E-Vac in order to dial in your vacuum and vacuum flow. EXAIR E-Vac generators are engineered for high efficiency and minimizing air consumption.

In-Line E-Vac Generators are compact and easily mount at the point of use. They can held in place by screwing them directly to your rigid compressed air line or by using one of our mounting clips. There are 7 models used with porous materials, such as carboard, with vacuum levels up to 21″ Hg and vacuum flows up to 18.5 SCFM. There are also 7 models to choose from for non-porous materials, such as glass, with vacuum levels up to 27″Hg and vacuum flow up to 15.8 SCFM.

Adjustable E-Vacs (below) allow easy adjustment, simply loosen the locknut and turn the exhaust to increase or decrease the vacuum flow. There are 4 sizes with vacuum up to 25″Hg and vacuum flow up to 81 SCFM. They are Engineered for high efficiency and minimize compressed air usage by adjusting the vacuum level to the application.

EXAIR has four cup styles to match and accommodate just about any size shape and material. Let’s look at the cups available and their characteristics:

Round Cups come in small and large sizes and work well with smooth flat surfaces . The round cups hold up well with time and grip well to vertical surfaces. Round cups without cleats are more flexible and work well in applications that do not require lifting heavy loads. Round cups with cleats

Oval Cups provide the most vacuum due to having a larger surface area. Shape matters: this is especially true for oval cups which have a higher suction power compared to round cups. The are designed to handle heavy objects such as flat rigid sheet materials.

Bellow Cups have an accordion shape and designed for textured, uneven surfaces. The folds are called convolutions and provide a collapsible area allowing the cup to compress when it touches an uneven surface.

Once you have selected the style and quantity of vacuum cups you can review the EXAIR Accessories that will compliment your project. EXAIR offers a variety of mufflers, tubing, check valves, fittings that will make it easier to build your vacuum system.

If you have questions selecting what is right for your needs please contact me or any of our other Application Engineers to help answer your concerns. Visiting our website http://www.EXAIR.com and viewing our blogs, videos and product lines is easy and helpful but if you have questions please contact me Eric Kuhnash or any of our Application Engineers to help answer your concerns.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK

Vacuum Generator System Selection – EXAIR E-Vacs

Published on by exaircorpLeave a comment

E-Vac Vacuum Generators are a highly efficient, versatile compressed air vacuum pump. Their versatility allows them to be adapted to many applications such as pick and place, clamping or vacuum forming. They’ve also been used in more unique applications like wood veneer pressing and basketball deflation.

EXAIR manufactures (3) types of E-Vacs – Low vacuum generators for porous materials, like cardboard, generating up to 21″ Hg with vacuum flows as high as 18.5 SCFM. Our high vacuum generators, designed for use with non-porous materials like glass or steel sheets, produce vacuum levels up to 27″ Hg and up to 15.8 SCFM of vacuum flow. The adjustable generators provide flexible vacuum performance, up to 25″ Hg and 81 SCFM,  which can be easily adapted to meet the application.

EXAIR E-Vacs provide instantaneous vacuum response, and are engineered for high efficiency to minimize air consumption.

 

When making a selection, there are a few key areas you want to consider:

Is the material porous or non-porous?

  • This will allow you to select the proper type of vacuum generator to fit the application and the type of vacuum cup best suited for the process.

 

What is the weight of the part and how will it be lifted?

  • If the part is being lifted where the vacuum cups will be positioned horizontally, like on top of a sheet of glass, you want to use a safety factor of 2 times the actual weight of the part. In processes requiring the cups be positioned vertically on the part, such as picking up a sheet of plywood and hanging it on an overhead conveyor, a safety factor of 4 would be used.

 

How many Vacuum Cups do I need?

  • Consider the quantity and placement to evenly distribute the weight for safely moving the material.
  • Depending on the maximum vacuum the generator produce, how much weight can each cup lift?
  • Make the cup selection per the following chart

 

Once you have selected the type and number of cups needed, you can then begin to look at which additional accessories items you might need.

  • Filters – supplying clean, dry air is key for maintaining optimal performance. An automatic drain filter  can be used to remove any water or contaminants in the supply line. If there is oil present, consider using an Oil Removal Filter.
  • Mufflers – help to reduce the noise level without restricting the airflow. We offer 2 different styles – Standard and Straight Through. Standards mufflers are a good choice where the supply air is clean and dry. These mufflers can only be used with the porous and non-porous generators. The Straight Through mufflers reduces sound levels by up to 26 dBA and are the better choice in processes where dirt or particulate may be present.
  • Tubing and Fittings – polyurethane tubing is available in 10′ sections up to 50′ for processes requiring the vacuum cups be placed in a location that wouldn’t allow for direct mounting to the NPT vacuum port on the generator or where multiple cups are needed. You want to keep the length of tubing as short as possible though for effective pickup and release time.
  • Check Valve – will maintain vacuum on the load if the supply pressure were to drop or be lost during operation.

For additional assistance selecting the proper E-Vac and accessories for your process, please contact an application engineer at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Help with Choosing an E-Vac Vacuum Generator

Published on by Russ BowmanLeave a comment

This is a pretty common question when it comes to Vacuum Generator use in pick-and-place application, and although we can’t boil it down to a simple table & formula based on mass (like we can with the Vacuum Cups themselves,) we can usually hone right in on it, if we have enough details of the situation. And, if questions remain, we can always test one to find out…we’ve got an Efficiency Lab.

That’s what I did, first thing this morning. I had the pleasure of speaking with a robotics instructor at a vocational school yesterday…his class was building a robot to enter in a competition, and one of the operations it needs to accomplish is picking up a golf ball and carrying it a certain distance.  This sounded like a great application for a small E-Vac Vacuum Generator, and, considering the potential leakage at the Vacuum Cup face from the dimples on the golf ball, my first instinct was to consider our Model 810002M E-Vac Low Vacuum (Porous Duty) Generator w/Muffler, and a Model 900766 Bellow Style Vacuum Cup, with a 0.73″ diameter face…our smallest, and ideally sized for a golf ball.  They, however, have a VERY limited supply of compressed air, so the difference between the Model 810002M’s compressed air consumption (2.3 SCFM @80psig) and the Model 800001M E-Vac High Vacuum (Non-Porous Duty) Generator w/Muffler (1.5 SCFM @80psig) was worth considering.  Also, we figured that they might be able to use a Model 900804 Check Valve, so the only time they’d need to supply air was to pick it up, and, possibly intermittently to maintain the vacuum.  So, golf ball in hand, off to the Efficiency Lab I went.  I also took our trusty video camera:

As you can see, it locked on to the golf ball instantly, and the Check Valve allowed the Vacuum Cup to hold the ball for over 13 seconds with no air flow to the E-Vac, proving that there isn’t much leakage at all past those dimples.  I suspect we’ll be seeing this robotics class team in the winner’s circle at the competition.

In most cases, the difference between 1.5 SCFM and 2.3 SCFM consumption may go unnoticed when picking a short-duration pick-and place vacuum generator.  The higher usage product’s supply pressure can always be regulated down to reduce compressed air consumption and use only what’s necessary to do the task…we, in fact, recommend that on ANY compressed air application.  In this case, though, it was worth finding out.

If you have a pick-and-place application that you’d like help with in selecting the right system, give me a call.

Russ Bowman
Application Engineer
(513)671-3322 local
(800)923-9247 toll free
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