EXAIR’s Reversible Drum Vac couldn’t be easier to operate. Thread it in to the 3/4 NPT vent connection on your drum lid, install the Standpipe & Hose on the 2 NPT bung, hook up a compressed air line to it, and you’re in business. As long as your compressed air is clean & moisture free, your Reversible Drum Vac will run like new for a long, long time.
Should you start to see a decrease in performance, though, the first thing you’ll want to do is verify the compressed air supply, especially if something’s changed:
Did you get a new hose? The Reversible Drum Vac uses 19 SCFM @80psig for rated performance. That’ll require a 3/8″ ID hose, assuming a length of no more than about 20ft.
Are there any restrictions in the line? The usual suspects are clogged filters, partially closed valves, or push-to-connect quick-connect fittings.
Are there any vacuum leaks in the hose, its cuffs, the drum, or either threaded connection? If the lid’s removable, is that gasket intact?
Pro tip: a pressure gauge, right at the inlet, will give you instant indication of an air supply issue with your RDV (or any compressed air-operated product.)
If you’ve eliminated all of those potential problems, it’s time to take a look at the Reversible Drum Vac itself. The Reversible Drum Vac has tight internal passages that contamination from even the cleanest compressed air systems can build up in, over time. Good news is, we made it super easy to disassemble & clean, and better news: this almost always restores it to as-new performance. We even have a video that walks you through it:
You may be surprised not at how much, but how little contamination you find inside the Reversible Drum Vac. We offer factory refurbishment service for them as well…the procedure in the video is step-by-step what that service consists of, except we also replace the Shim, O-Rings, & Float, and when we reassemble it, we verify performance on the same fixture that every single new Reversible Drum Vac that we build gets tested on. Recently, a customer sent a Reversible Drum Vac in for refurbishment services after we’d spent some time talking on the phone, exchanging emails, and even a brief Engineering Consultation web meeting, troubleshooting their loss of vacuum. I was particularly curious about this one, so when it came in, I tested it (on our calibrated test fixture) for performance, and found it was only generating about 22% of rated vacuum, and only 17% of rated flow. I figured it was clogged (with a capital CLOGGED) so I match marked the body & plug (just like we show in the video) and took it apart:
I was frankly surprised at how little contamination (which appeared to be rust from the customer’s compressed air piping system) caused such a dramatic loss of vacuum.
We then completed the Refurbishment Service and tested it again. Performance was verified to be within specification for a new High Lift Reversible Drum Vac.
I offer to share the Cleaning & Refurbishing video with just about anyone who calls to discuss performance (or lack thereof) of their Reversible Drum Vac. Some still want to send theirs in for Refurbishment Service, and that’s fine. If you have a Reversible Drum Vac that’s not working properly, I’m here to help you get the most out of our products — any of them — give me a call.
Russ Bowman, CCASS
Application Engineer Visit us on the Web Follow me on Twitter Like us on Facebook
In industrial manufacturing, compressed air is the unsung hero powering tools, machinery, and processes across manufacturing, painting, blasting, and beyond. But here’s the catch: moisture. That sneaky water vapor lurking in your compressed air lines can wreak havoc, causing corrosion, freezing, and contaminating sensitive equipment. Deliquescent driers are low-maintenance systems designed to tackle humidity head-on. In this blog, we’ll dive into what makes these driers tick, their pros and cons.
What Are Deliquescent Driers, Anyway?
Picture this: a simple tank packed with hygroscopic (water-loving) salt tablets that dissolve into a brine as they absorb moisture from compressed air. That’s the 1000-foot view of a deliquescent drier. Unlike refrigerated or desiccant dryers that rely on complex refrigeration cycles or regeneration, deliquescent driers use chemistry to do the heavy lifting. The process is elegantly straightforward:
Incoming air enters the bottom of the vessel, preheated from compression and loaded with water vapor.
It flows upward through a bed of deliquescent desiccant—typically formulated from salts like calcium chloride, lithium chloride, or potassium chloride.
The salts “deliquesce” (hence the name), attracting and dissolving water vapor into a liquid brine that collects at the base.
Dry air exits the top, with a pressure dew point suppressed by about 15-20°F below the inlet temperature, depending on conditions.
No electricity, no moving parts—just pure, passive drying. These driers have been a staple since the 1940s, especially in rugged settings like petrochemical plants, outdoor blasting ops, or mobile equipment where reliability is the largest concern.
Why Choose Deliquescent Driers? The Pros (and a Few Cons)
Deliquescent driers aren’t for every scenario, but when they fit, they’re a game-changer. Let’s break it down:
The Advantages:
Zero Energy Consumption: No power required means lower operating costs and no electrical hazards in wet or explosive environments. Ideal for remote sites or intermittent use.
Rugged and Portable: Mount them indoors or outdoors—they thrive in extreme temps, even subzero conditions, with the right setup. Perfect for mobile contractors in painting or abrasive blasting.
Low Maintenance: Just drain the brine every 8-hour shift and top up the desiccant a few times a year. A sight glass lets you monitor levels at a glance.
Cost-Effective Upfront: Cheaper to buy and install than high-tech alternatives, with no filters or separators to fuss over.
The Drawbacks:
Limited Dew Point Control: They suppress dew point by a fixed amount (e.g., 20°F), so hot inlet air means warmer outlet air—fine for many apps but not ultra-dry needs.
Corrosion Potential: The brine is salty and corrosive, so vessels need robust coatings, and downstream lines require after filters to catch salt carryover.
Pre-filtration Required: Oil from compressors can foul the desiccant, so a coalescing pre-filter is a must.
In short, if you’re blasting in humid conditions, painting in the field, or running air tools in cold weather, deliquescent driers deliver freeze-proof, reliable performance without the fuss.
At EXAIR Corporation, we’re keen on compressed air efficiency. The attention to detail we pay to our products – from design, to manufacturing & assembly, to availability, and right on through to technical support – bears out our commitment to helping you get the most out of your compressed air system. If you’ve got questions, Give me a call.
I was once on a local theater’s website, ordering tickets to an upcoming show that my wife and I were excited to see. I had the option to pay online and have a digital code emailed to me in lieu of a real live paper ticket. Can you believe they wanted to charge me almost $2 A TICKET for that?!? I adamantly refused (by that I mean I clicked the mouse extra hard on the “Will Call” button before completing my payment)…and saved that $4 (almost) for something REALLY important.
The night of the show, there was a 20-minute line at the Will Call window. Folks who had opted for the digital code were doing a quick scan with their smartphones and walking straight into the theater. I used the $4 I saved to partially pay for a $10 glass of wine from a concession kiosk in the lobby, as a peace offering for my lovely bride. That was indeed “something REALLY important.”
Another time, I was ordering a sump pump backup system for our house. I had the option of paying extra for the deluxe system, which came with all the fittings and a special tool to make installation a bit easier. Even though the ‘deluxe’ system adder was probably a bit more than the cost of the fittings from my local hardware store, I paid the “convenience fee” and got the deluxe system anyway. For the record, during the installation, I realized I would have bought an incorrect fitting at the local store which would have forced an emergency trip while I had the water turned off in my whole house. THAT was an inconvenience I was glad to have avoided.
Similarly, you can buy any EXAIR product with, or without, accessories that’ll make for simpler installation, improved performance, and to ensure it does what you want it to do. Some of these are product-specific, but many are suitable (and recommended) for use with any of our products:
Filter Separators
Good engineering practice calls for point of use filtration for any compressed air operated device. Even if you have the best intake & discharge filters on your air compressor, trace amounts of contaminants can sneak through, pipes can rust, and water vapor that the dryer doesn’t catch can condense. Particulates can build up and eventually clog the tight clearances in many engineered compressed air products, and if you’re using air for cleaning, drying, etc., keep in mind that whatever’s in your air will get on your product. Moisture isn’t always as big of a deal, but it can freeze inside Vortex Tubes, Spot Cooling Products, Cold Guns, and Cabinet Cooler Systems. That’s why we include Filter Separators in our Air Knife, Air Wipe, Static Eliminator Products, Line Vac, Adjustable Spot Cooler, Cold Gun, and Cabinet Cooler System Kits.
Automatic Drain Filter Separators come in sizes from 1/4 NPT to 1-1/4 NPT, for compressed air flows up to 400 SCFM.
Oil Removal Filters
These aren’t always needed, but we have them if your application calls for it. Some of the “usual suspects” are food & Pharma (see above “whatever’s in your air will get on your product”), blowoff prior to painting (the smallest amount of oil on the surface causes a phenomenon known as “fish eye” and it looks exactly like that sounds), or when your compressor is known to have oil carryover.
When properly installed downstream of an Automatic Drain Filter Separator (left,) an Oil Removal Filter (center) will provide clean, oil free air to the Pressure Regulator (right) and all downstream components.
Pressure Regulators
One of our Six Steps To Optimizing Your Compressed Air System is to control the air pressure at the point of use to minimize air consumption. In other words, find the supply pressure for your product that gets the job done, so you don’t use any more compressed air than you have to. Like the Filter Separators above, these come with many EXAIR Intelligent Compressed Air Product Kits.
Pressure Regulators “dial in” performance to get the job done without using more air than necessary.
Mounting Brackets and Coupling Kits
Most of our Filter Separators, Oil Removal Filters, and Pressure Regulators can be attached to a wall, panel, etc., with a Mounting Bracket, and can actually be attached to each other with a modular Coupling Kit. These parts simplify the installation, ensure they are oriented correctly, and minimize the chance for air leaks.
Filters (left) and Pressure Regulators (center) can be mounted using Brackets, and they can be connected together with Modular Couplers (right).
Silencing Mufflers
Many EXAIR products are engineered to develop a boundary layer of low velocity air flow that greatly reduces the sound level during operation. Other products use a venturi mechanism to draw a vacuum (Reversible Drum Vacs and E-Vac Vacuum Generators) or a Vortex Tube to generate cold air flow. The air flow from these products cannot be subjected to back pressure, and, without anything to mitigate the sound pressure generated by the rapid pressure drop as the air exits, they can be quite loud. For these, we have Silencing Mufflers that, except for the largest & most powerful of these products, reduce the sound level to be compliant with OSHA Standard 1910.95 Maximum Noise Exposure Limits.
From left to right… Reclassifying Mufflers offer the highest noise level reduction, eliminate oil mist, and come in sizes from 1/8 NPT to 1 NPT. Sintered Bronze Mufflers are low cost and compact, with threads from #10-32 to 1-1/2 NPT. Straight Through Mufflers use an internal sleeve of sound reducing foam, with threads from ¼ NPT to ¾ NPT, with male threads on one end and female threads on the other. Heavy Duty Mufflers have an aluminum shell and an internal stainless steel screen that keeps contaminants like rust from being ejected in a dangerous way. We have them in ¼ NPT and ¾ NPT sizes.
Solenoid Valves (left) are available for 120VAC, 240VAC, and 24VDC in sizes from 1/4 NPT to 1 NPT. We offer manual Ball Valves in sizes from 1/8 NPT to 1-1/4 NPT.
Swivel Fittings, Stay Set Hoses, and Magnetic Bases
EXAIR Super Air Nozzles are threaded for installation with common air pipe & hose fittings. If the pipe isn’t pointed in the exact right direction, a Swivel Fitting gives you 50° of adjustability. If the pipe isn’t quite close enough to what you want to blow off, Stay Set Hoses come in lengths of 6″ to 36″, and when bent to aim the Air Nozzle, they ‘stay set’, as advertised, until they need to be moved. If a pipe doesn’t exist and you need to run an air hose from the nearest drop on the header, Magnetic Bases can support the Air Nozzle and a Stay Set Hose to get the air where you want it. They even have shutoff valves to turn them off when they’re not in use (that’s a good thing; see above).
Save installation time AND get your blowoff pointed in the right direction!
Hoses and Compressed Air Fittings
If you need one of the aforementioned air hoses to reach a Magnetic Base or to supply a Safety Air Gun, we have two diameters to choose from – 3/8″ ID (1/4 MNPT threads on the ends) and 1/2″ ID (1/2 MNPT threads on the end), and we can make them to any length you need. And, while our selection probably isn’t quite as comprehensive as your local piping supply shop, we stock a number of pipe nipples, Couplers, Reducers, Tees, and Elbows that are commonly used with our products. So – like my backup sump pump deluxe kit, we can put all the fittings you may require in the same box for you.
Contact an Application Engineer if you have ANY questions about how to properly supply compressed air to your EXAIR products.
At EXAIR, we’re here to make sure you get the most out of our products, and your compressed air system. If you need accessories to help with that, give me a call.
Russ Bowman, CCASS
Application Engineer Visit us on the Web Follow me on Twitter Like us on Facebook
Back when typewriters were an author’s main tool, movies & TV shows would often show an author experiencing a condition known as “writer’s block”, sitting at his desk with a wastebasket overflowing with crumpled papers representing failures-to-launch of their latest work.
For you younger folks, a “typewriter” is a standalone word processor with an integral printer.
The reason I tell you all this, dear reader, is because I had a bad case of “writer’s block” going on with this blog until I had the pleasure of discussing Industrial Housekeeping Products with a caller from a major tire manufacturer. Their needs were typical – and familiar:
Electric powered shop vacuums did the job, but….
They’re loud.
They break down.
They can’t use them everywhere. Their safety rules say they’re not allowed to run them in areas where the floor, equipment, etc., gets wet. (That’s a good rule, by the way…electrocution is serious business).
They’ve got compressed air drops EVERYWHERE…maybe more common even than 115VAC receptacles.
Since it’s a tire plant, they’d be used to vacuum up exactly what you’d expect: scrap bits of rubber, ranging from shavings to pellet-sized chunks.
If they were using it for particularly dense or abrasive material, we’d have talked about the Heavy Duty Dry Vac. If it was for dusty materials (especially critical dust containment of toxic or hazardous materials), the Heavy Duty HEPA Vac would have been discussed. If liquid transfer was involved, we’d have talked about Reversible Drum Vacs, EasySwitch Wet-Dry Vacs, or Chip Trapper Systems. If it was for small jobs and something handheld was desirable, the Vac-u-Gun might have been worth a look (actually…more on that in a minute). But this was a “textbook” fit for a Chip Vac System – consider:
Compressed air powered – no electric motor to burn out.
No moving parts – supply it with clean air, and it’ll run darn near indefinitely, maintenance free.
Compressed air powered, part 2 – no risk of electrocution.
Quiet – at 77dBA, the Chip Vac is 50% quieter than typical electric vacs.
Whatever your needs, EXAIR has a Chip Vac System to meet them!
If you’ve got an open top drum, Model 6193 (55 gallon) or 6193-30 (30 gallon) comes with everything you need for a basic setup. Model 6293 (or 6293-30) adds a Drum Dolly and Tool Holder. Or, for a complete system, ready to go right out of the box, Model 6393 (55 gallon), 6393-30 (30 gallon) or 6393-110 (110 gallon) adds the Drum, a 20ft compressed air supply hose with shutoff valve & gauge, and upgrades to a Static Resistant Hose and Heavy Duty Aluminum Tools. For smaller jobs and/or if space is a premium, Model 6193-5 comes with a 5 gallon container, and Model 6293-5 adds a drum dolly to that.
