People of Interest: Giovanni Battista Venturi March 15, 1746 – April 24, 1822

Giovanni Battista Venturi was born in 1746 to an affluent family in Reggio, Italy. An aspiring student, Giovanni was ordained as a priest and a professor by the age of 23. An avid historian of science at the University of Modena, he was the first to emphasize Leonardo da Vinci as a scientist rather than just an artist as he’s more commonly known. Despite his love for history, it wasn’t long before the University of Modena became aware of his talents in mathematics where they appointed him as professor of geometry and philosophy in 1774. During his tenure at the University of Modena, Giovanni was promoted to the Professor of Experimental Physics, served as the Duke of Modena as the State engineer and auditor, later serving diplomatic roles in both France and Switzerland.

Giovanni is most well-known for his work in developing what is now known as the venturi effect. In 1797, he published a study on the flow of water through short cylindrical tubes. It wasn’t until 1888 that Venturi’s design was applied to something practical when a man named Clemens Herschel received a patent for the first commercial venturi tube. The original purpose of the venturi tube was to measure the amount of water used in individual water mills and is still used to this day as a means of measuring fluid flows.

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Venturi Tube

The venturi effect is a principle in fluid dynamics and states that a fluid’s velocity must increase as it passes through a constricted pipe. As this occurs, the velocity increases while the static pressure decreases. The pressure drop that accompanies the increase in velocity is fundamental to the laws of physics. This is known as Bernoulli’s principle. Below is an illustration of how the venturi effect works inside of a constricted tube.

venturi

In everyday life, the venturi principle can be found inside of many small engines such as lawn mowers, gas powered scooters, motorcycles and older style automobiles. Inside the carburetor, there is a small tube through which filtered air flows from the intake. Inside of this tube is a short narrowing. When the air is forced to constrict, its velocity increases and creates a vacuum. This vacuum draws in fuel and mixes with the air stream causing it to atomize.  As the throttle valve is opened further, more fuel is forced into the engine. This increases the RPM and creates more power.

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In-Line E-Vac

This principle is also applied to EXAIR’s line of E-Vac products to create vacuum. The .gif below illustrates how an In-Line E-vac works. (1) Compressed air flows through the inlet (2) and is directed through a nozzle, constricting the flow of air. (3) As the air stream exhausts, it expands causing a decrease in pressure and an increase in velocity prior to passing through the venturi. (4) A vacuum inlet tangential to the primary airflow is located at the suction point between the orifice and the venturi. (5) The airflow that is drawn through the vacuum inlet mixes with the primary airstream, then exhausts on the opposite end.

The venturi effect is used in a variety of other EXAIR products used for cooling, drying and cleaning, in addition to the vacuum generators. If you have a process in your facility that may benefit from an Intelligent Compressed Air solution, give us a call. We’d be happy to discuss your application and implement a solution to both reduce your compressed air costs and improve worker safety.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@exair.com
Twitter: @EXAIR_TD

Photo: Venturi Tube with labels by ComputerGeezer an Geof.  GNU Free Documentation License

EXAIR E-Vac Vacuum Generator, How to Pick the Correct One

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.  To determine when to use the Adjustable or the In-Line, see this Blog by Russ!

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Adjustable E-Vac
In-LineE-VacFamily
In-Line E-Vac

 

 

 

 

 

 

The biggest factor and the first place to start is to 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 allows 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.

If you want to see them both in action check this video out! 

E-Vac Video
Click the Video to Watch!

Both the Low Vacuum (for non-porous material) and High Vacuum (for porous material) E-Vacs come in 7 different sizes, ranging from light to very strong vacuum capabilities, to match any application. Special Kits are  available as a way to experiment with an assortment of vacuum cups to determine the best configuration.

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EXAIR E-Vac Vacuum Generator

If you have questions about vacuum generation and the E-Vac 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.

Jordan Shouse
Application Engineer

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Building an E-Vac Vacuum Generator System

EXAIR’s In-Line and Adjustable E-Vacs are a powerful compressed air powered vacuum generator. They’re a low-cost way to create a vacuum for a variety of different applications: pick and place, clamping, chucking, lifting, surface mounting, and vacuum forming are just some of the possibilities. Both the In-Line and Adjustable E-Vacs are available in a variety of different sizes and flows and can accommodate a wide range of applications.

With no moving parts to wear out, EXAIR’s E-Vacs are virtually maintenance free when supplied with clean, dry compressed air. In-Line E-Vacs are available in two different styles: High Volume, Low Vacuum for use with porous materials and Low Volume, High Vacuum for use with non-porous materials.

For pick and place or lifting applications, vacuum cups will be necessary. With a wide variety of different vacuum cups available: Small Round, Large Round, Oval, and Bellows, we can accommodate nearly any size or shape material. For heavier materials, round cups with cleats provide rigidity and ensure that the load remains stable. For applications on textured or uneven surfaces, Bellows style cups have convolutions that allow for the cup to quickly decompress when it touches the surface of an uneven part or material. To determine the most suitable cup, we must consider the weight of the material and the orientation it will be lifted.

Vacuum cups

If it is being lifted with the vacuum cups positioned horizontally, use a safety factor of 2. For applications where the part or material will be lifted vertically, use a safety factor of 4. This safety factor is then multiplied by the weight of the material. You’ll then need to determine how many vacuum cups are needed. No more than 4 vacuum cups should be used with any one E-Vac. Consider the size/shape of the material to be lifted and place vacuum cups accordingly to evenly distribute the weight. Heavier and larger materials may necessitate the use of more than one E-Vac.

The weight a particular cup can hold at a given pressure is shown in the chart below. Once you’ve determined a suitable cup based on the weight and orientation of the lift, a variety of other accessories are also available.

vacuum cup weights

The vacuum port of the E-Vac has an NPT thread, vacuum cups can be installed directly in this inlet. For applications where the vacuum cup(s) are remotely located, we offer polyurethane vacuum tubing as well as a variety of different fittings to connect them. Both 1/4” and 3/8” O.D. sizes are available in 10’ lengths up to 50’. Simply indicate the model number of the tubing and add the length with a “-“ at the suffix. In addition to fittings and tubing, vacuum check valves are also available. These can be beneficial if there is potential for fluctuations in the compressed air pressure or supply. In the event that there is a significant drop in pressure or loss of compressed air supply, the check valve will ensure that the load remains stable.

To minimize the sound level and ensure you’re adhering to OSHA 1910.95, we have Standard Mufflers as well as Straight Through Mufflers. The Straight Through Mufflers offer the best level of sound reduction, up to 26 dBA!!

E-Vac Mufflers

With all of the different options making a selection can seem like a daunting task. If you’re struggling to determine the most suitable E-Vac and Accessories for your application, give an Application Engineer a call today!

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@Exair.com
Twitter: @EXAIR_TD

EXAIR Vacuum Generators and Accessories

So, you’re looking at picking out a vacuum generator for your application but don’t know what accessories you need? Well here is a little overview of EXAIR’s E-Vac system’s accessories that you have to choose from. The E-Vac has a variety of uses from pulling a vacuum on a chamber to lifting Concreate cinder blocks. Here at EXAIR we offer everything that you may need to get started; this includes mufflers, vacuum cups, hose, and fittings.

Vacuum cups for E-Vac generators

Every time I hear someone talking about trying to pick something up the first line that comes to mind is “The claaaaaaw.”. But sometimes a claw or gripper isn’t the answer for the solution; using a variety of vacuum cups one can practically pick up almost anything. We offer four different kinds of vacuum cups to choose from stock; available are small and large Round, Oval, and Bellow styles. Round cups are more suited to being used on 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; the folds provide a collapsible area that allows the cup to compress and seal on the uneven surface.

EXAIR’s Standard and Straight Through Muffler

Next up is the mufflers; EXAIR’s mufflers do just that, they muffle down the sound generated by the E-Vac. There are two different types of mufflers that are available; these are the Standard and the straight through mufflers. The Standard muffler is designed to be attached to the discharge end of an in-line      E-Vac and has a closed end. These are best suited for applications that are free from dust and debris. The straight through muffler is open all the way through and are more suited to applications were dirt dust and debris is present. The straight through style also offers the best sound level reduction, up to 26 dBA.

Lastly the E-Vacs have an NPT threaded connection that will allow for a suitable connector to be properly installed. From here different connectors can be used to attach the various amounts of vacuum cups. The connectors provided are Push-In Connector Type Fittings of assorted styles available with our polyurethane tubing to make the installation and plumbing a cinch.

If you have any questions or want more information on EXAIR’s E-Vacs and their Accessories. Give us a call, we have a team of application engineers ready to answer your questions and recommend a solution for your applications.

Cody Biehle
Application Engineer
EXAIR Corporation
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