5 ways to maintain your positive displacement blower

A positive displacement blower is the heart of your and many other operations.  It is what keeps your conveyor belts moving, your oils flowing, and employees working.  Taking good care of your positive displacement blower mean little or no downtime in your operation.  The problem is it works so well that we might forget to take care of it time to time.  But when your positive displacement blower stops working that means your business stops working.  Maintenance is the key to keeping your equipment working for a long time.

By not taking care of your positive displacement blower, you risk the chance of losing money and time on costly repairs.  Not only do you spend money on fixing the equipment but your business will incur expenses on downtime. 

Yes, it’s too late for your positive displacement blower

Never start or run your positive displacement blower while it is low in oil.  Once you launch the machine, there is no going back.  You might as well call the maintenance crew right as you turn on the switch.  Turning it on while it’s low on juice will cause an immediate failure on the gears. 

Imagine turning on the food disposal with a spoon stuck in the drain.  The same thing will happen to the rotors lobes.  The longer this goes on, the more damage will occur.  The end clearances will change, thrusting the rotor into the free end plate and the bearings will fail. 

Before starting your positive displacement blower for the day, check the levels.  Even consider putting a procedure in place to check all of the machinery before getting the conveyors going.  Just a few minutes will save you from lost time and damage.

Lubrication is vital

Not only should you check the levels but you need to keep you oil clean.  Just a car, a positive displacement blower needs lubrication to keep the rotors moving smoothly.  Positive displacement blowers need their oil changed every 500-1000 hours depending on the condition of your facility.  The dirtier the facility and harder you work your positive displacement blower, the more often you should change the oil. 

You think 500 hours is not a long time but think about it like a car.  Most manufacturers ask that you change the oil every 3000 miles.  If you’re driving your car 30 MPH, that’s 100 hours of operation.  

Feed it; It’s Starving!

Your positive displacement could be suffering from a starved inlet which is a condition where airflow entering the blower is not sufficient.  The air flow is not cooling the machine down as it works.  Keep an eye on the signs of a starved inlet like browning of the pain on the blower, yellowish “straw’ color of the rotors indicating the internal temperature to be around the 430-degree mark, and even some cases of temperatures as high as 640 degrees.  Your positive displacement blower is overheating at this point.  As soon as you see some strange discoloration, it’s time to take action. 

Again, keeping a checklist on how to maintain your equipment is key.  You can prevent a starved inlet by paying attention to your machine.  Monitor your inlet filter restriction indicator and visually inspect the positive displacement blower.  Do not depend on the indicator alone as sometimes it might be too late.  Just like your oil, change the inlet filter regularly.  Like you’re a/c in your home, you want your air to be clean, free of debris and muck.

Just too much pressure

Your positive displacement blower is a machine.  It will keep going, and nothing can stop it from doing what it does best.  If anything gets stuck in the air pipe, the machine will keep working, not matter what.  The machine will self-destruct while it wants to keep moving. 

To prevent over-pressure, consider installing a pressure release valve on the discharge of each blower.  Just a simple switch will give relief to your positive displacement blower.  If the problem persists, you need to do some investigating.  Hopefully, you do not have to tear your machine apart.  The last thing you want to do is sit in a pile of pieces trying to find where the problem started in the first place.  Though this is not a piece of furniture from IKEA as it has tons of instructions, you don’t want to be responsible for a leftover screw.  Better call the pros to figure where that piece belongs.

It’s getting hot in here

Machines get hot.  Your cell phone, your laptop, your DVR, your car, and even your positive displacement blower.  There are other reasons why your machine might overheat besides a starving inlet.  The recirculation of airflow from the blower discharge to the blower inlet is obstructed, there is a throttling blower discharge trying to reduce the airflow.  Either way, the positive displacement blower is trying to breathe.  When it can’t, it overheats. 

Though there are not many glaring signs your machine is not working, discoloration will give you a clue that something is wrong.  Just like too much pressure, consider installing a switch at the blower discharge.  When doing this, install the heat exchanger before the recirculation loop to the blower inlet.   Always make any changes to your positive displacement blower while the valves are wide open.  The blower is meant to flow air.  While working on the machine, it needs to breathe as if it were working in your factory. 

Treat your machine as a family member as it is the heart and soul of your business.  Your conveyor belts will not move, and your pumps won’t pump if anything happens to this piece of equipment.  It is a workhorse so it will work hard and keep working until it cannot anymore.  Give your positive displacement blower functioning by properly maintaining its pieces.  Keep your machine lubricated, check your levels, and look for any differences in how your machine looks or functions.  Any indication of a difference is worth looking into for a few moments.  There are a lot of years left of a great positive displacement blower.  Give it the chance to keep your business moving.   

CLAY MORRISESP