Month: January 2016

Pushing Hot Parts with Compressed Air More Efficiently

Published on by John BallLeave a comment

A manufacturer of forged, steel parts contacted EXAIR today and spoke to me about an application that was really giving them some trouble.

The application involved placing a molten piece of steel into a die.  The press would come down and mold the piece into a ring shape.  As it opened, a solenoid valve connected to a compressed air supply was actuated to push the falling part with the compressed air to a bin behind the press.  The manufacturer made a home-made nozzle by flattening a piece of ¾” pipe and directing it at the part.  (Reference picture below).  The operator had a cycle time of roughly 8 seconds.  During that time, the compressed air was actuated for 1 second to push the part away from the die.  An issue occurred if the part rotated 90 degrees as the die opened, and the compressed air would shoot through the open center of the part without pushing it into the bin.  The part would rest on the bottom die, causing a slowdown in production because the part had to be removed manually.

Forging press
Forging press

The part weighed 2.2 lbs. (1 Kg) and had an outer diameter of 3.5” (89mm).  The customer was operating the ¾” pipe “nozzle” at 90 psig (6.2 bar), and it was located 12” (305mm) away from the die.  This gave me some good information to find an appropriate nozzle.  While reviewing the force and air pattern needed, model 1112SS (3/4 NPT Stainless Super Air Nozzle) would be the best product.  This Super Air Nozzle would be able to withstand the radiant heat within the application and can produce a force of 4.5 lbs. (2 Kg) at 80 psig (5.5 bar).  At 12” (305mm), it produced an airflow diameter of 7.5” (191mm).  Even if the part rotated, the air pattern and force was large enough to push the part from the die even if it rotated, eliminating the need for manual intervention.

Not only did the production rate get back on target, but as an added bonus, Model 1112SS was able to save the customer compressed air. The advantage of using the Super Air Nozzles, is that they entrain ambient air to work with the compressed air, increasing the overall mass flow toward the target, making it much more efficient than a flattened pipe.  Even with the compressed air being turned on for 1 second during the 8 second cycle time, the Super Air Nozzle  is projected to save the customer over $1,500.00/year when comparing its air consumption to that of an open 3/4″ pipe.

Whenever you have an urge to flatten an end of a pipe to create a home-made nozzle, you should contact an Application Engineer at EXAIR to see if we can help. Like the customer above, we were able to solve their production problem, and able to save them money.

John Ball, Application Engineer
johnball@exair.com
@EXAIR_JB

Undersized Plumbing Creates a Performance Problem

Published on by Lee EvansLeave a comment

Sometimes we get calls or emails from our customers experiencing a problem with their application already using EXAIR products.  These calls can range from difficulties associated with installation angle, installation, or, in many cases, the compressed air plumbing to the product itself.

That was the case in the application of the photos above.  The end user had been using our model 6084 Line Vac to move plastic pellets from the floor to the top of a machine hopper, and they needed to increase the flow.  The problem, was that they weren’t getting the performance from the 6084 that they thought they should.

Chip Vacuum 1
                                                                 EXAIR model 6084 Line Vac used for conveying plastic pellets

 

Chip Vacuum 2
Model 6084 Line Vac used to convey plastic pellets from the floor to the top of a machine hopper

 

Given the bulk density of the plastic pellets in this application, the end user should’ve been able to move more than enough material in the time they desired for the application needs.  But, instead, the Line Vac was moving little-to-no material and even “stalling” – a condition in which the conveyed material could enter into the Line Vac and then cease to convey.

What we found, after exchanging contact information and discussing the photos above, is that the compressed air line feeding the Line Vac is too small, creating a pressure drop and leading to an inadequate compressed air flow.  This, in turn, leads to lower air velocity at the exhaust of the Line Vac, which simultaneously means lower vacuum and material flow at the inlet.

The end result is the condition described by the end user – a low flow, or no-flow, of the material being conveyed.

After our discussion the end user set out to make the required change to the supply line, providing proper flow to the Line Vac at the proper pressure, and moving the material as required.

It’s always rewarding to help an end user solve their problems.  If you have an application problem and think EXAIR might be able to help, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Let’s Talk About Cooling. Yes, In January.

Published on by Russ BowmanLeave a comment

Well, we’re right smack dab in the middle of January, and it’s time for the annual reminder (to myself, mainly) that I surrendered my right to complain about the cold when I moved here from Florida (on purpose) some 24 years (and 2 months, 8 days, and a handful of hours) ago.  Not that I’m keeping track.  You can follow this link (and this one, and this one) to some of my former rantings on the subject.

After an admittedly mild December in Ohio, the struggle became real this week.
After an admittedly mild December in Ohio, the struggle became real this week.

But, as the title implies, I AM going to talk about a need for cooling. Of course, no matter how cold it is outside, there are many, many processes in industry that can get quite hot. Here’s one of them:

A company that operates injection molding machinery had a big problem: their machines’ molds were cooled by chilled water, and as they aged, they developed leaks, allowing water into the mold cavities. This, of course, ruined the product. To make things worse, the passages that the chilled water flows through are cast right into the machine body, so permanent repair essentially means that these bodies (the main part of the machinery) have to be replaced, at significant cost.

Last summer, they went looking for alternate methods of cooling, and found our Vortex Tubes. After some experimentation, they determined that (8) Model 3240 Vortex Tubes (2,800 Btu/hr, Maximum Cooling Power) would replicate the cooling previously provided by the chilled water systems.

EXAIR Vortex Tubes are a quick & easy method to get cold air, on demand, wherever you need it. Just like this.
EXAIR Vortex Tubes are a quick & easy method to get cold air, on demand, wherever you need it. Just like this.

They’ve since outfitted all of their injection molding machines with these, and have dodged a very expensive replacement of machinery for the foreseeable future.

If you’d like to find out how an engineered product from EXAIR’s comprehensive line can take the heat off (literally or figuratively) an application you’re struggling with, give us a call.

Russ Bowman
Application Engineer
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Atomizing Spray Nozzles – Categories and Selection

Published on by exaircorpLeave a comment

EXAIR Atomizing Nozzles are a reliable way to clean, cool or coat a wide variety of products. Constructed of 303ss, the units are extremely durable, provide superior corrosion resistance and are able to withstand temperature up to 400°F.

No Drip Atomizing Nozzle
EXAIR Atomizing Spray Nozzles atomize fluid in a wide range of spray patterns for various applications.

The Atomizing Nozzles are separated into 3 categories – Internal Mix, External Mix and Siphon Fed:

Internal Mix Atomizing Nozzles require a pressurized liquid source and compressed air source and mix the two flows inside the air cap to produce a fine mist of atomized liquid. These nozzles are better suited for applications that don’t require independent control of the air or liquid and are suitable for fluids up to 300 cP.

External Mix Atomizing Nozzles require pressurized liquid and air as well, but allow for independent control to reach higher flow rates with more precise control. With the liquid and air being mixed external to the nozzle, they are able to handle higher viscosity fluids (300+ cP).

Siphon Fed Atomizing Nozzles are the ideal choice for applications without a pressurized liquid source. The liquid can be gravity fed or pulled from a siphon height up to 36″.  Due to the liquid not being pressurized, these nozzles are limited to fluids of 200 cP or less.

With so many choices, it may seem somewhat cumbersome in making the correct selection. To simplify the selection the process, there are 5 common considerations:

  1. How much liquid flow do I need?
  2. Is the liquid pressurized?
  3. What is the viscosity of the liquid?
  4. How wide of an area needs to be treated?
  5. What type of spray pattern fits the application?

The answers to these questions will allow you to make the best selection to fit your needs. Of course if you still are unsure, you can rest easy as one of our engineers is readily available should you require additional assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN