Tag: windshield

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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Cabinet Cooler Systems – Around The Clock (And Calendar) Heat Protection

Published on by Russ BowmanLeave a comment

So it was 19°F (-7°C) when I walked outside this morning. The layer of ice on my windshield was thin, but particularly stubborn, and I muttered under my breath. I have no business complaining about the cold…see, I moved to Ohio (on purpose) from Florida, in 1991. In November, to be exact. I still remember where I surrendered my “complain-about-the-cold” card:

If you’re headed north on I95, the next sign you’ll see is in Georgia. And if you’re not careful, you can end up “Up North.”

Why am I writing a blog about solutions to heat problems when, even though I do have a really nice pair of gloves, my fingers still aren’t even really thawed from ice removal duty this morning? Well, I’ve got three reasons:

1. Outside temperature doesn’t necessarily have any bearing at all on the temperature inside. Sure; there’s a reason we call July and August “Cabinet Cooler Season” – summer heat will do a number on sensitive electronic & control panels in spaces with no climate controls, but the problem goes away as winter approaches. In fact, there’s even such as thing as a cabinet HEATER, if the equipment in question is exposed to the elements.   Sometimes, though, heat is an issue year ’round…think blast furnaces, boiler rooms, foundries, chemical plants.  If your process generates heat, it’ll affect a control panel in the dead of winter just the same as on the dog days of summer.  We can quickly and easily specify the right Cabinet Cooler System for you with just a few key pieces of data…here’s a link to our Cabinet Cooler Sizing Guide if you want to find out.

2. It’s not winter all over the world.  Here in the Midwest United States, I full well realize we’re just gearing up for windshield scraping, snow shoveling, slipping-on-the-ice (some people call it skating and do it intentionally) season.  But right now, our friends in the Southern Hemisphere are getting ready for heat waves, sunscreen, and (hopefully) air conditioning.  So, in essence, they’re moving towards what we call “Cabinet Cooler Season.”

3. Our Cabinet Cooler Systems are so great, the 316SS Cabinet Cooler Systems with Electronic Temperature Control are actually up for Plant Engineering’s Product of the Year Award.  Because of their 316SS construction, they’re optimally suited for installation in harsh or demanding locations.  The Electronic Temperature Control offers continuous indication of internal temperature, and the ability to change the thermostat setpoint with the push of a button.  If you’re a current user, and you agree that they’re great, we’d appreciate your vote.  If not, I’m reluctant to encourage you to vote for it, but I suppose I can’t stop you from taking my word for it…

EXAIR NEMA 4X 316SS Cabinet Cooler System with Electronic Temperature Control installed on control panel in a pharmaceutical plant.

If you’d like to talk about protecting sensitive electronics from the heat, or from the environment, or both, I’d love to hear from you…give me a call.

Preventing Quality Defects in Laminated Autoglass

Published on by Dave WoernerLeave a comment

This week I had the opportunity to work with a customer that manufactures automotive glass. Part of the process of manufacturing the glass is to apply a thin plastic film of polyvinyl butyral (PVB) in between glass sheets.

 

This creates the laminated safety glass that protects passengers from flying glass shards in the event of an accident.

glass
The customer was having a quality problem. Glass was being rejected on their low volume compound curved glass production line for debris being trapped between the layers during the laminating process. We worked on identifying how the dust could be introduced into his laminating process. First, each of the glass panels are cleaned by hand with a cleaner and a soft cloth to remove any dirt, grease or oil that can be left behind from production, shipping, or handling. The soft cloth can leave behind some lint.

On the high production line, a cleaning roller would remove any lint left behind on the flat glass. On the curved glass of the low production line, the curvature of the glass prevented the roller from applying even pressure across the glass and was leaving lint of the cleaning cloth is left behind.  This lint will become a defect in the glass after the glass is cured in an oven.

Ion Air Gun

I recommended the customer use an Ion Air Gun immediately after the hand cleaning cloth step since the Ion Air Gun is also a manual, hand held product. The PVB is pulled from a stack of thin film which generates a static charge from dragging one sheet over another and increasing the chance that lint will stick. The Ion Air Gun will remove the static charge and blow off the lint just prior to lamination. If this was a high volume product, I would have recommend one of our long one piece Super Ion Air Knives to cover the whole piece of glass in a single blow off. Because this was already a manual process due to a low volume specialty glass, the Ion Air Gun is the best product for the job.

Dave Woerner
Application Engineer
Davewoerner@EXAIR.com
@EXAIR_DW

 

Image from me and the sysop. Creative Commons