Tag: venturi vacuum generator

E-Vac’s: Choosing The Right Vacuum Generators and Cups For Non-Porous Object Lifting

Published on by Russ BowmanLeave a comment

For years, users worldwide have been building pick-and-place vacuum lifting systems using EXAIR E-Vac Vacuum Generators and Vacuum Cups. One of the very first calls I took after I started here in 2011 was from a customer who wanted to make an automated bench-top system for use in the packaging of small blister packs of consumer products. These products were small, so it was fairly easy to specify a compact and inexpensive setup that was easy on his compressor load. Which was good, because his compressor wasn’t all that big either. Here’s how we went about it:

Each product going into a blister pack was about the size of a roll of pennies, but much lighter, as they were hollow plastic tubes with lip balm in them. Our Model 900762 1″x0.5″ Oval Vacuum Cups were a perfect fit – they’ll hold half a pound with only 5″ Hg vacuum, so even if they didn’t make a perfect seal on the tube (which weighs just shy of an ounce), they’d work just fine.

With objects that weighed next to nothing, and a smooth, non-porous surface for the Vacuum Cups to seat on, we didn’t need a whole lot of vacuum generation power, so we went with a Model 810002M In-Line E-Vac High Vacuum Generator. Using a selection of our Vacuum Tubing & Connectors, they constructed an automated lifting system to package six of the tubes in their blister packs at a time.

This was a small, simple system that didn’t require an awful lot of engineering…our smallest Vacuum Cups and E-Vac Vacuum Generators were more than capable of handling the load. Other times, we have to (EXAIR Application Engineers actually say we “get to”) use math & physics to come up with the right system. Even when they require some of the proverbial “heavy lifting,” they can still be fairly straightforward. Consider this application for a steel plate:

  • 1/2″ steel plate, 4ft x 6ft, weighing ~490lbs.
  • Picking up from the top of a stack and placing onto a laser cutter.

First, we start with the selection of vacuum cup size. For a plate of this size, multiple cups are necessary – even if one vacuum cup was rated for the weight we’re considering, that would be incredibly unstable. Additionally, if one cup fails to make a good seal on the surface, more cups provide redundant protection against potentially dropping the load. We can use this Vacuum Cup Selection Table from the catalog:

Per the instructions, we multiply the weight of the object (490lbs in this case) by a safety factor of two if we’re picking it up horizontally from the top, or four if we’re picking it up vertically from the sides. Our Model 900761 6″ Large Round Vacuum Cups are rated at 148.8lbs each, and since:

980 lbs (2x the plate’s weight) ÷145.8 (rating in lbs for each Cup) = 6.7

We need at least seven of them to safely handle this load. Let’s use eight, though, for symmetry. If you’re wondering why I picked the weight capacity associated with 21″Hg when our High Vacuum In-Line E-Vacs can generate 27″Hg, it’s just in case one of the cups doesn’t make a perfect seal to the surface…we still want to be able to hold the plate, even if there is a little vacuum leakage. So, we’re overcompensating to add to our already calculated safety factor in the application.

Next, we’ll select our E-Vacs. For safety’s sake (I can’t stress how badly I DON’T want to be party to dropping a 490lb steel plate on anything, or anyone), we’ll use four E-Vacs. Since each E-Vac will be servicing two of our largest Vacuum Cups and the vacuum lines aren’t all that long, but the weight of the object being picked up is significant, I’ve picked our Model 810013M High Vacuum E-Vacs for their moderate vacuum flow (1.31 SCFM @24″Hg) and high vacuum level rating (27″Hg):

Each of our four E-Vacs will pull vacuum on two vacuum cups, in a ‘crisscross’ pattern so that if one fails, it doesn’t unbalance the load.

If the object is to be picked up from the side, then we use a 4x safety factor for the object’s weight. For example, a customer who replaces truck windshields transports them in vertical racks on their service trucks. They wanted to use one E-Vac and three Vacuum Cups for the manual lifting rig they had designed. One piece of a two-piece windshield is about 2ft x 3ft, and weighs about 50lbs.

200 lbs (4x the windshield’s weight) ÷ 3 (number of Cups specified) = 66.7 lbs per Vacuum Cup

Based on a weight rating of 73.2lbs @21″Hg, we used three of our Model 900759 4.25″ Large Round Vacuum Cups for this application. Since an operator wipes down the glass immediately before picking it up, and has good control of the lifting rig (so they can ensure the cups are properly seated on the surface), we selected a Model 810006M High Vacuum E-Vac, which still has a decent amount of vacuum flow (0.77 SCFM @24″Hg) in case of any leakage, and a 27″Hg vacuum level rating.

EXAIR also carries a comprehensive selection of Connector Fittings and Vacuum Hose or Tubing to connect these kinds of systems together. If you want to spec out a lifting/pick-and-place system, I’m here to help – give me a call.

Russ Bowman, CCASS

Application Engineer
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Necessity Is The Mother of Invention

Published on by Brian FarnoLeave a comment

Necessity is the mother of invention, or something like that. My garage is riddled with “tools” that have come from necessity at any specific point in time.

Things like a socket that has been ground down around the outer wall to fit into a space that was too tight for anything else. Maybe it is a combination line wrench that has been torch-heated and bent to go around another hard line. Eventually, it will need to be reheated and bent back to near straight. I even have some special ground screwdrivers and punches that have been used on various projects. At the moment, I can’t remember whether one was for installing a retaining ring in a master cylinder on a brake system or for removing a key from a shaft. The unique purpose eventually fades from memory after you do it so many times.

The one that I have used most recently is a mason jar that has some fittings attached to the lid and has some tubing coiled up inside. If you have ever worked on car or motorcycle brakes with me, then there is a very good chance we have used this tool at some point.

This tool started as it was purchased, with a hand pump and a small fluid container. After starting at EXAIR and bleeding several motorcycle brake systems, I recognized the need for something easier and less back-and-forth than the hand pump. So I placed a small E-Vac onto the system instead of the hand pump. I blogged about this back in April 2010. That was one of my first blogs here at EXAIR as an Application and ever for that matter. After the addition of the E-Vac, and working on some larger systems, I realized the small container was not sufficient and needed to be emptied too frequently. I needed a chamber that would handle vacuum and not degrade with brake fluid exposure. I just happened to have been canning some tomatoes and saw an extra mason jar sitting there. A couple of fittings later and I now have a 1-qt capacity pneumatic brake bleeder system.

Fast-forward to last week, and I was using the same mason jar vacuum system to draw all the power steering fluid out of two vehicles and perform a fluid change on them. This system has been loaned out to many of my friends over the past decade and always comes back to sit on the shelf until it is needed again. I may even be using it this weekend to help with a new clutch install with a friend.

At EXAIR we have a fairly extensive listing of products available in stock configurations. However, we also love to talk about how we can modify them to suit special circumstances. Please let us know if you want to discuss how we can help you create a purpose-built system or tool to suit your needs.

    

Brian Farno, MBA – CCASS Application Engineer

BrianFarno@EXAIR.com
@EXAIR_BF

My Take on EXAIR’s Adjustable E-Vacs: Wear-Free Vacuum Technology

Published on by Jordan T ShouseLeave a comment

When it comes to innovative solutions for industrial applications using compressed air, EXAIR has long been a trusted name, and our Evac vacuum generators are no exception. These compressed air-powered devices are designed to create a powerful vacuum with remarkable efficiency, making them ideal for a wide range of tasks—from pick-and-place operations to bag opening and even vessel evacuation. Whether you’re lifting parts, opening bags, or clamping materials, EXAIR’s E-Vacs offer a versatile, maintenance-free solution that optimizes performance while having ZERO moving parts to wear or breakdown, and let’s be honest, mechanical vacuum pumps are always breaking down. Let’s dive into what makes these vacuum generators stand out and explore some of their key variants.

EXAIR E-Vac Vacuum Generator

Our Adjustable E-Vac Vacuum Generators are the ones that typically fall into the “number of other applications” category above. While the In-Line E-Vacs are compact and reliably generate rated vacuum on demand, the Adjustable E-Vacs have some distinct advantages in certain cases:

Larger throat diameter. In-Line E-Vacs have a very tight throat, which generally doesn’t matter if they’re just hooked to Vacuum Cups that’ll be placed on a relatively clean surface. The wider throat of the Adjustable E-Vacs means that they can pass small debris from less-than-pristine surfaces that a Vacuum Cup might lift, or shavings that might fall into a work holding fixture on a machine tool. They can even pass liquids, so they’re sometimes used for small spill cleanup.

Adjustable E-Vac: How it works

Adjustability. It’s right in the name, of course, but it IS a big deal. While you can regulate the supply pressure of almost any compressed air operated device to vary the performance level, you can thread the plug into, or out of, the body of an Adjustable E-Vac to literally put it in a whole new performance band. This is beneficial if you’re picking up, or holding down, pieces of different sizes, shapes, and weights. Just loosen the locking collar, make the adjustment, tighten it back up, and it’s ready for use.

If you have questions regarding our Adjustable E-Vacs, or how to solve any issue with an EXAIR Intelligent Compressed Air® Product, feel free to contact EXAIR . One of our Application Engineers would be pleased to help you determine your best solution.

Jordan Shouse
Application Engineer

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E-Vac Porous vs Non-Porous

Published on by jasonkirbyLeave a comment

The E-Vac by EXAIR is an efficient compressed air-powered vacuum pump designed for rapid and reliable pick and place operations, offering instantaneous response times for improved productivity and versatility in various industrial applications. The E-Vac vacuum generators are designed with advanced technology to optimize performance and reduce air consumption. This contributes to lower operational costs by minimizing energy use, ultimately enhancing productivity in processes requiring vacuum handling.

When determining which E-Vac type, you have to consider the material you will be lifting is porous or non-porous. An example of a porous material would be wood, which will allow some air to move through the material. An example of a non-porous material would be glass, which will not allow air to move through the material.

Porous low vacuum generators max. vacuum= 21″Hg (71 kPa).

Non-porous high vacuum generators max. vacuum= 27″ Hg (91 kPa)

Low vacuum units up to 21″ Hg (71 kPa) with vacuum flows up to 18.5 SCFM are typically used for porus materials such as cardboard and delicate materials. The relatively lower level vacuum prevents warping, marring, dimpling or disfiguring of the surface due to excessive vacuum. This style generates more vacuum flow to overcome porosity and leakage through the target material.

High vacuum units up to 27″ Hg (91 kPa) with vacuum flows up to 15.8 SCFM are typically used for non-orous materials such as glass, steel sheet, and plastic. There are 7 In-Line models that vary by flow to accommodate larger and more vacuum cups in an application.

For additional information on the E-Vac by EXAIR, or any of our EXAIR compressed air products, please feel free to contact our Application Engineers. We are always happy to assist you with your product or application questions.

Jason Kirby
Application Engineer
Email: jasonkirby@exair.com
Twitter: @EXAIR_jk