Contaminated Air Supply Leads To Unwanted Results

IMG_5570
Rust from the air supply found inside a compressed a Reversible Drum Vac.

One of the greatest attributes of EXAIR products is their ability to stay in operation for years on end without any maintenance.  With no moving parts to wear out, there really is little-to-no upkeep required.  So, when we receive notice from a customer that an EXAIR product is not working properly, we most always seek to establish the pressure, volume, and quality of the compressed air supply.  By examining these three variables, we can usually pinpoint the source of the performance discrepancy.

I had an exercise in this routine a few days ago with a Reversible Drum Vac (RDV).  The RDV had arrived at EXAIR after the customer noticed a drop in performance.  The RDV went from operating normally to gradually loosing strong vacuum when vacuuming liquids out of a coolant sump.

The end user and I discussed the air supply pressure, line size, and available volume of compressed air to operate the RDV which all seemed to be in order.  Compressed air supply pressure was 80 PSIG, they were using the EXAIR supplied (properly sized for the product) compressed air hose, and the unit had functioned in this exact setup for some time, so we were confident in the ability of the compressed air system to supply adequate volume.

In most cases, when an RDV gradually loses vacuum, or experiences a change in performance without a change in application parameters, contaminants from the compressed air system can be found inside of the RDV.  And, that is exactly what happened here.

IMG_5565
Reversible Drum Vac “plug” – notice the rust on the everything below the O-ring (everything in contact with the compressed air supply)

I first tested the RDV for vacuum level and flow, both of which were low.  When I disassembled the RDV I noticed what looked like rust on all surfaces which are in contact with the compressed air stream (photo above).

IMG_5567
Internals of the Reversible Drum Vac “body”; littered with rust

Then, I peered into the body of the drum vac and saw the root of the problem – dirt and rust from the compressed air system had accumulated within the RDV, restricting compressed air flow and causing the decay in performance.

IMG_5568
Rust and shim as they were dumped out of the Reversible Drum Vac body
IMG_5569
Another photo of the rust

After a quick cleaning of the RDV, performance was perfect and the RDV was ready to go back into operation.  The end user and I discussed my findings along with proper air filtration to prevent a similar occurrence in the future.  They were glad to know their RDV was in working order, and we were both glad to confirm the root cause.  With a new filter separator installed at the compressed air line feeding this RDV, trouble-free and maintenance-free performance can be expected for a long time to come.

If you have a similar application need, or think an EXAIR solution may benefit your process, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s