Dust collection systems play a critical role in ensuring efficient production and workplace safety. Without the dust collector operating properly, production may slow or halt altogether, costing a company thousands per day. However, maintaining the system can be costly and time consuming if not done properly and regularly. Fortunately, there are multiple strategies to reduce the time and cost of operating your dust collection system. In this blog post, we will review five effective ways to minimize your operating costs and maximize efficiency.
The points outlined below offer benefits to companies large and small, with dedicated maintenance crews or a single superman holding everything together.
#1 Preventative maintenance plan
The most important thing anyone can do to ensure their dust collector runs efficiently and cost-effectively is to implement a preventative maintenance plan. Performing regular preventive checks and maintenance helps you avoid significant issues that can be costly and time-consuming to resolve. A preventive maintenance plan, at the very least, guarantees that you examine common wear points to address any potential problems before they escalate into major issues. Benefits of a preventive maintenance plan
Daily monitoring of differential pressure gives you a sense of when to change the filters. This enables you to find replacement filters without incurring rush or expedite fees, and schedule the work for a convenient time that minimizes production disruptions.
Fix the small things before they cause larger/expensive issues
Reduce down-time by scheduling maintenance to all items that need attention at one time.
#2 Understand how your dust collection system operates and what happens when things get out of alignment.
We understand that the dust collector is typically the final piece of equipment in a lengthy production line.Which means that changes or problems with upstream processes may, or may not, have a big impact on the dust collector. Understanding your dust collection system and its weak points will help you prevent, quickly identify, and address problems caused by upstream issues.
For example, a Nomex (Aramid) felt filter bag has an operating temperature of 400°F, with surges to 445°F. If you have a temperature spike in the production process causing temperatures in the baghouse to exceed 400°F, it will reduce the life of the filters. They may not fail immediately, but the media will be weakened and more susceptible to tearing. Understanding this, you may keep a closer eye on the baghouse to catch bag failures or move up a scheduled changeout to prevent unplanned downtime if bags start to fail.
Changes in temperature, dust loading, moisture levels, and other factors can significantly impact the performance and wear and tear of your dust collection system.
Understanding how these variables affect your dust collector can also help prevent issues, additional maintenance costs, and costly shut-downs. Making changes to upstream processes to increase filter life or reduce dust collector issues is one cost-effective way to extend filter life and reduce overall operating costs.
#3Maintain the pulse cleaning system
It’s important to ensure that the pulse jet cleaning system on your dust collector is operating properly to keep the filters clean and the system running efficiently. Doing so helps extend the lifespan of your filters, reduces maintenance costs, and minimizes downtime. Failing to do so may result in blinding of filters, excessive compressed air consumption, and reduced suction at pickup points. Maintenance can include:
Ensuring that valves open and close properly and without any problems.
Confirming that valves and fittings do not have any leaks.
Checking the pressure regulator and control panel to make sure the settings are accurate.
Ensuring that the on/off times are set correctly. If pulsing On-Demand, verify that the high and low limit settings are still appropriate.
#4 On-Demand Cleaning
On-Demand cleaning is a great, and fairly easy way, to reduce operating costs and wear on your dust collection system. An on-demand cleaning system monitors the pressure drop (or differential pressure) in the dust collector and turns on the pulse cleaning system, only when needed. This reduces the amount of compressed air used and reduces wear on the filters and pulse valves. Reducing compressed air consumption can have significant cost savings when combined with longer filter and diaphragm life.
The on-demand cleaning system uses a pressure module or photohelic to read the pressure drop across the filters. The “high-limit” and “low-limit” are set on the timer board and tell the timer board when to start and stop the pulse cleaning. As pressure builds and hits the “high-limit” the cleaning system kicks on and pulses the filters. As the filters are cleaned the pressure will gradually drop until it hits the “low-limit”. Once the “low-limit” is reached, the cleaning system turns off, conserving compressed air until the pressure builds up to the “high-limit” again and the cycle starts over. To learn more about on-demand cleaning, you can watch ourHow Does On-Demand Cleaning Work with a Timer video.
#5 Perform fan maintenance
It is recommended to include a weekly and monthly check of your fan as part of your preventative maintenance plan. While fans may be easy to overlook, improper maintenance can lead to significant problems. The fan is the heart of the dust collector and, therefore, needs to be kept in good working order to ensure optimal performance. Fan maintenance can include the following:
Weekly: Belts, unusual noises
Monthly: Grease bearings and check all lubrication points and for improper sheave alignment, proper tensioning of v-belt drives.
To download a free PDF version of this Dust Collection Start-Up Guide simply click this link here.
As factories and industrial plants resume production after a shut-down period, employers are faced with the responsibility of minimizing work hazards by instituting best practices and safety measures. This is where a dust collection start-up guide will help.
Starting up your dust collection system the right way will make sure your equipment is operating properly while also protecting the safety of your workplace and workforce. The steps in this dust collection start-up guide will also ensure your system is in good working order so you don’t have to worry about an unexpected shutdown.
To streamline your start up process and make it as hassle-free as possible, we’ve prepared a comprehensive checklist and action item notebook. These resources can help you address any issues promptly. Our guide is broken out into four sections:
Best Practices for Dust Collection Start-Up
Dust Collector Start-up Checklist
Action Item Checklist
Maintenance Questions to Consider
Part 1: Best Practices for Dust Collection Start-Up
Power Down & Lock Out
Before you begin start-up, maintenance or troubleshooting on your dust collection system, your first and most important step is to power down and lockout any machinery. Securing your baghouse for personnel entry can include locking down your rotary valve, locking your blower, or sealing off any adjacent baghouse compartments. Taking these initial steps provides a safe working environment and will
ensure that accidents are minimal.
Additional Watchman & Communication Plan
Designate an additional crew member as a watchman. They should be present to ensure safety procedures are being followed and can immediately assist should any complications occur. It’s important to let your team know what work is being done, where, and at what time. This allows others to re-schedule any work that could impede on a safe start-up of your dust collection system.
Combustible Dust
If you are working with combustible dust, make sure the dust levels inside of your system are well below being explosive. Perform all hot work, like welding, well outside of the perimeter of your dust collector.
Emergency Plan
A total shut down and lock out of your dust collector will minimize safety hazards, but you shouldn’t hesitate to formulate a retrieval plan should an emergency occur.
PPE (Personal Protective Equipment)
OSHA requirements for protective gear will vary based on your application. Basic protection can include a hard hat, safety glasses, gloves, and a face mask. Before start-up or entry into your baghouse system, make sure that your crew is supplied with and compliant in wearing safety gear required for your application.
Start up your system by powering on your control panel and your fan.
Check fan for excess vibration.
Check your controller to ensure all valves are running.
Check your differential pressure to make sure pressure is within limits
If your differential pressure is in the blue range noted above, perform a leak detection test.
Part 3: Maintenance Action Item Checklist
Record maintenance issues you’ve encountered during your start-up inspection that require attention below. Note the issue, part type, part number and quantity impacted. Download a PDF copy here.
Part 4: Time Saving Maintenance Questions to Consider
To eliminate unexpected plant shutdowns due to baghouse issues should you consider a spare set of filters and diaphragm repair kits
Do you need to adjust your preventative maintenance schedule? If COVID-19 has altered your production and maintenance schedule, consider what you need to adjust going forward.
Do you have the specs for each of your dust collector parts listed in one central location? If not, here is a sample spec template for Filter Bags and Cartridge Filters. Having this ready can help your dust collection supplier get you the right parts quickly, affordably and accurately.
For more complimentary dust collection maintenance resources, visit our blog with over 50 articles on dust collection design and maintenance. You’ll find additional help on the following topics and more.
About U.S. Air Filtration, Inc.
OUR COMPANY
U.S. Air Filtration was established in 1987 to serve the needs of industries requiring air pollution control systems. We aim to meet and exceed United States EPA standards for air quality. Over the years, we have worked on projects ranging from $20,000 to over $3 million. Our Founder, Engineering and Sales Personnel has been active in the industry for over 30+ years.
OUR MISSION
To help our customers achieve peak production by providing exceptional service, products and expertise in air pollution control.
OUR VALUES
Our values are the foundation for our actions as leaders, colleagues, employees and citizens. At U.S. Air Filtration, our values incorporate our conduct towards our customers, our suppliers, our fellow employees, and the general public.
To download a free PDF version of this Dust Collector Maintenance Guide simply click this link here.
Our dust collector maintenance guide contains troubleshooting and maintenance tips to keep your dust collection system running at peak efficiency.
Table of Contents
1.USAF Pulse-Jet Baghouse Dust Collector Features
10. Cartridge Dust Collector Change Out Instructions
2. USAF Cartridge Dust Collector Features
11. Dust Collector Troubleshooting
3. Five (5) Most Commonly Replaced Dust Collector Parts
12. Baghouse Entry Procedures
4. When is it time to change your filters?
13. How Differential Pressure Works In Your Dust Collector
5. How to Detect a Dust Collector Leak
14. Guide to On-Demand Cleaning
6. How to Install a Snap Band Dust Collector Filter Bag
15. Dust Collector Preventative Maintenance Plan
7. My Pulse Valve Is Not Working What's 7. Wrong?
16. Dust Collector Maintenance Checklist
8. How to Replace Your Dust Collector Diaphragm Valve
17. Dust Collector Start-Up Check List
9. How to Replace the Solenoid’s in Your
Pulse Valve
18. Maintenance Action Item Check List
5 Most Commonly Replaced Dust Collector Parts
Watch Video Above
Proper upkeep of your dust collector is essential to long term health and performance. As your dust collector ages, system parts will be prone to wear and tear. To keep your system at peak performance, take note of the five most commonly replaced dust collector parts and how you can identify maintenance issues.
To know when it’s time to replace your parts, look out for these common warning signs. The more you are prepared now, the better you will be at avoiding the high costs that quickly escalate with unscheduled downtime.
Timer Board
No power to the timer board
Pulse valve not pulsing
Pulse valve leaking air due to small electrical charge coming from timer board
Solenoid
Leaking pulse valve
Pulse valve wont fire/pulse
Rubber on plunger is worn
Solenoid post is bent
Plunger is rusted/corroded and can’t move freely
Diaphragm Kit
Pulse valve is leaking air
Weak pulsing
Filter bags not being cleaned, increased differential pressure
Is your spring broken?
Valve
Leaking air even after replacing diaphragm kit and checking solenoid and timer board
Stripped or damaged threads
Cracking on valve housing
Stops pulsing
Pulse is weak
Filters aren’t cleaning properly
Filters
High differential pressure
Loss or reduction of velocity/ suction at pick-up points.
Dusting from dust collector exhaust
When is it Time to Change Your Filters?
Watch Video Above
How do you know when it’s time to change out the filters in your dust collector? The video above walks you through the troubleshooting steps you can take to determine if it’s time for a filter change out.
There are typically two reasons people change out their filters:
The build-up of filter cake is so excessive that it is blinding your filters.
You have a hole/leak in your filter(s).
Influences on the Life of a Filter
The following are several factors that impact the life of your filters:
Air to cloth ratio
Cleanliness of compressed air
Volume of dust loading
Presence of chemicals – oils, acids, etc.
Size of dust
Operating temperature
Presence of membranes or coatings
Frequency of cleaning cycle
Dust characteristics (powdery, sticky, shape)
Average differential pressure
Air velocity through the filters
Proper cage fit
Moisture in the dust
Proper installation
Ambient air moisture
How to Detect and Solve a Dust Collector Leak
Watch Video Above
Have you noticed a continuous emission of dust from your collector? It’s usually indication that the problem is inside your system and a common culprit is a leak in your filters. Here are some of the more common causes to look out for.
If you’re not able to diagnose your problem with a quick visual observation, then a simple die test is your next step. A die test uses fluorescent leak powder and concentrates it at it’s entry points into the clean air plenum. It’s these entry points that are your leaks. Check out the short video guide above that talks about the main causes, how to perform a test, and how much leak powder you’ll need for your dust collector system.
How to Install a Snap Band Filter Bag
Watch Video Above
Time for a change out or need to install new filter bags? Learn how to properly install a filter bag into your dust collector’s cell plate in the video above.
A double beaded snap band filter bag can be used in a wide variety of dust collectors. In a pulse-jet or reverse air dust collector, you’ll typically see it as the bag’s top configuration. In a shaker dust collector you may see the snap band as a bottom configuration. The snap band is a flexible steel band double beaded gasket that helps create a dust tight seal. You may have also heard of the snap band referred to by other names such as:
Double Beaded Snap Band Names
Beaded Snap Band Top
Snap Band Top (Double Beaded and not the same as a single snap band top)
Double Beaded Snap Ring
My Pulse Valve is Not Working, What’s Wrong?
Watch Video Above
Is your dust collector showing signs of trouble? It could be your diaphragm valve.
Have you ever had a pulse valve in your dust collector stop working? In this video we will be helping you troubleshoot your dust collector valves and various issues that might be causing the problem.
Common Symptoms of a Worn Out Diaphragm
Rubber has crack or holes in it
Diaphragm kit is pitted, allowing air to leak through
Any holes tears or imperfections indicate it’s time to change it out
Is your spring broken?
Once you’ve diagnosed your issue down to an old worn out diaphragm, you’ll need to get it replaced. The short video above provides step-by-step instructions on changing out a diaphragm, as well as some helpful tips.
How to Replace Your Solenoid Valve
Watch Video Above
Are the solenoid’s on your pulse valve damaged? Learn the warning signs and how to replace your solenoids.
In the video above, we’ll walk you through how to replace a broken solenoid. If your has any of these symptoms below, you’ll need to get it replaced before it escalates into a larger maintenance issue with your dust collection system.
Warning of a Damaged Solenoid
Rubber parts are worn
Solenoid post is bent
Plunger is get pitted
Due to environmental conditions, the coil itself has suffered an electrical short.
This results in weakened copper wires.
Cartridge Dust Collector Change Out Instructions
Watch Video Above
Filters are one of the 5 most commonly replaced dust collector parts. Getting your filters replaced quickly and accurately will help you avoid a costly shut down. In this video below, we are showing how easy it is to change filters in a USAF cartridge collector in less than 30 minutes.
Removing Filters
Remove outer door/handle assembly by turning the outer handle counterclockwise. Set outer door/handle assembly aside once free of dust collector.
Remove inner door/handle assembly by turning the inner handle counterclockwise. Set inner door/handle assembly aside once free of dust collector.
Remove filters by grabbing bottom of filter and pull straight out – being careful as filter may be dirty.
Installing Filters
Insert new filter cartridge into the dust collector with the gasket facing the cell plate (gasket side first).
Insert second cartridge, if necessary depending on your DC model, in the same manner as the first (gasket side first).
Take inner door/handle assembly and thread onto the rod by turning clockwise. Tighten the inner door/handle assembly so it compresses the cartridge filter gaskets by roughly 50%. This ensures the filters seal against the cell plate and the inner door seals the back of the cartridges.
Take the outer door/handle assembly and thread onto the rod by turning
clockwise.
Tighten the outer door/handle assembly until the outer door gasket is compressed against the dust collector creating an air tight seal.
Caution: Be careful not to over tighten doors as the doors may bend or threads
on handle and rod may be damaged. Tighten by hand.
Caution: Do not use sharp instruments or unusual force when installing filters. They are fragile!
Dust Collector Troubleshooting
Are you having problems with your dust collector? Troubleshoot your dust collector now.
Is your dust collector showing signs of trouble ahead? Keeping your dust collector healthy will prevent unscheduled down time, production loss, or a costly shutdown. Here are some of the common indicators your dust collector is having issues, and how you can troubleshoot them.
High Pressure Drop
Check timer indicator lights to see if it is functioning properly and pulsing the valves. Replace fuse or timer.
Check air pressure line regulator for proper pressure and leaks. Maintain 80 to 90 psi in header.
Check hopper discharge and 55 gal drum lid for leaks allowing re-entrainment of dust. Repair seal or joints if leaking.
Check differential pressure lines (tubing) for plug or breaks allowing faulty readings.
Moisture in the dust causes a hard dense cake, which may blind the filter media.
Check air supply for clean dry, oil-free air. Faulty air systems will coat the filter on the inside and blind the filter causing high-pressure drop and premature
replacement. Always maintain clean dry air for the cleaning system. Attempt to dry the tubes by circulating clean warm air through the collector and going through several cleaning cycles. Empty the hopper. Check the process to prevent condensation. If Nanofiber cartridges are exposed to high moisture, water or liquids of any kind they may need to be replaced.
A Reduction in Pressure Drop Accompanied by a Dirty Exhauster Output
1. A solenoid valve may be stuck open or a diaphragm may be ruptured.
This can be detected by listening to each valve at the unit for constant airflow noise. Inspect rubber diaphragms and or solenoid seals and replace as needed. Open top doors and identify which blow pipe the air is flowing from. In turn this will identify the failed valve or solenoid assembly. Inspect diaphragm valve for failed diaphragm or small particle seated on diaphragm. Clean or replace as warranted.
Baghouse Entry Procedures
Performing maintenance or troubleshooting the interior of your baghouse can be dangerous. Here are some basic baghouse entry procedures to minimize your risk for accidents and hazards.
Power Down & Lock Out
Before you begin any maintenance or troubleshooting on your dust collection system, your first and most important step is to power down and lockout any machinery. Securing your baghouse for personnel entry can include locking down your rotary valve, locking your blower, or sealing off any adjacent baghouse compartments.
Also, make sure to shut off the compressed air supply to the pulse jet cleaning system and allow the system to cycle until the pressure is relieved before entering the baghouse. Taking these initial steps provides a safe working environment and will ensure that accidents are minimized.
Safety in a Confined Space
The inside of your dust collection system is almost always defined as a “confined space”. No matter the application, it’s best to ensure you have safety guidelines in place whenever entry into your baghouse needs to occur. Here are some of the general safety precautions you can take. Designate an additional crew member as a watchman. They should be present at the entrance point to ensure safety procedures are being followed and can immediately assist should any complications occur.
Communication
It’s important to let your team know what work is being done, where, and at what time. This allows others to re-schedule any work that could impede on safe entry into your baghouse.
Combustible Dust
If you are working with combustible dust, make sure the dust levels inside of your system are well below being explosive. All hot work, like welding, should be performed well outside of the perimeter of your baghouse. If hot work must be done
inside the baghouse, thoroughly purge the space with clean air until dust is no longer present.
Emergency Plan
A total shut down and lock out of your baghouse will minimize safety hazards, but you shouldn’t hesitate to formulate a retrieval plan should an emergency occur while employees are in inside the confined space.
PPE (Personal Protective Equipment)
OSHA requirements for protective gear will vary based on your application. Basic protection can include a hard hat, safety glasses, gloves, and a face mask. Before entry into your baghouse system, make sure that your crew is supplied with and compliant in wearing safety gear required for your application. You can find additional information on OSHA’s website about personal protection equipment hazards and solutions:
Differential pressure is a critical tool to make sure your dust collector is operating properly. In the video above, we’ll answer these top questions about differential pressure and how to use differential pressure to keep your dust collector at peak performance.
Top Questions about Differential Pressure
What is differential pressure?
How does differential pressure work?
How can I use it to better maintain my dust collector?
What do sudden changes in differential pressure mean?
My differential pressure reading is high. What can I do to fix it?
My differential pressure reading is low. What can I do to fix it?
What differential pressure should my dust collector be at?
Since every dust collection system is different DP readings are relative and should be compared to the collectors baseline levels.
A dust collector with brand new filters usually sees a DP reading of one to two inches. As the filters age and become more entrained with dust the differential pressure levels over time, near the end of the filters life the DP will be around six
inches and stay there even after the cleaning cycle has run.
Running a collector consistently above six is not recommended since it will likely cause a noticeable drop in plant suction and lead to faster dust entrainment and shorter filter life.
Guide to On Demand Cleaning
Watch Video Above
Pulse Jet Technology and On Demand Cleaning
Pulse jet cleaning is the most common type of dust collector available today and makes up nearly 50% of all new dust collector installations. In a pulse jet dust collector, filter bags are cleaned when a high pressure jet of air, or compressed pulse, is sent through the system to shock the bags and remove and fracture the dust cake. One advantage of pulse jet dust collectors is the bags can be cleaned while the dust collector is still running so plant production and processing can continue without interruption.
It’s important that bags are cleaned regularly to improve airflow through the system, prevent plugging from dust build up, and improve pick up velocities. But it may be time consuming and labor intensive to know how frequently and how often the bags need to be cleaned. On demand cleaning is an automated cleaning system for your dust collector that can improve your dust collectors efficiency and performance while reducing energy consumption and labor costs.
How On Demand Cleaning Works
In a pulse jet dust collector, as dust starts to cake on the bag the differential pressure between the dirty air environment and the clean air environment increases. With on demand cleaning, the control panel is set by the operator to clean the bags only when the differential pressure reaches a high range, then the system will pulse down to a lower range. Cleaning pauses until the differential pressure reaches the high range once more and the system will automatically pulse down again. This continues as an ongoing cycle that is performed the entire time your dust collector is running.
Check out the video above to learn more about what on-demand cleaning can do to improve your dust collector and your operation.
Dust Collector Preventative Maintenance Plan
How do you ensure your dust collector is running at peak efficiency? By being proactive with a maintenance plan.
Following a maintenance plan for your bin vent or cartridge collector will help you address any issues before they create a larger issue. Some benefits include:
On-Going Maintenance Procedure (may not apply to all models)
1. . Check compartment differential pressure model inside the panel for normal
operating range
10. Air Moving Equipment: Fans should be mounted on rigid foundation or supports.
For specific requirements, see fan manufacturer instructions in this manual.
2. . Observe if timer properly operates all pulse valves
11. Check the anchor bolts periodically to see that the vibration has not loosened or
damaged the fittings. Bearings should be periodically lubricated in accordance with
the bearing manufacturer’s lubrication instructions. Bearings should be removed,
inspected, and replaced, if necessary, as soon as excessive fan shaft vibration
becomes apparent. Also, check the shaft itself for such damage as scoring or heat
cracks. Never over lubricated bearings.
3. Check hopper dust level. Dust collectors are not designed to hold material.
12. . Impellers should be inspected at regular intervals for imbalance due to
deposited materials on the blades. Critical clearances between impeller, inlet rings,
and fan housing should be checked and maintained in the same conditions as when
the fan was installed. Similarly, the conditions of key ways and/or setscrews should
be checked.
4. Check the air pressure to the solenoid valves. Air pressure to the header should
range between 70 and 90 psi. NEVER MORE than 100 psi. If more pressure is required
to clean the filters then there is a problem with the filter media and or a problem
with the particulate flows and density. High air pressure will cause failure in the
diaphragm valves.
13. Belt tension should be maintained to prevent undue slippage or unnecessary
stress on bearings (both motor and fan).
5. . Lubricate fan bearings monthly if applicable.
14. Most fan motors are mounted on sliding bases. Make sure the base is secure.
6. Check damper valves for proper seating
15. Large fan motors may be supplied with a pivoting motor base. This type of base
automatically controls belt tension to respond to each change in load when
properly adjusted. The tension is determined by the amount of offset of the motor
with respect to the pivot point. To level the motor, loosen the cradle bolts at the
ends of the pivot and adjust the take up screws on the lower part of the base until
the motor is level. Tighten the cradle bolts.
7. Inspect filter media monthly for wear and replace if necessary, as indicated by
dust emission from discharge of fan or stack.
16. . Worn belts should be replaced; thus, spar V-belts should be maintained in stock.
To change V-belts, loosen the bolts holding the motor to its base, remove worn belt
and replace with new one. Make adjustments for proper tension and tighten bolts
securely.
8. Paint to guard against corrosion.
17. . V-Belt sheaves should be replaced when groove wear interferes with the efficient
functioning of the drive.
9. Maintain door seals and gaskets and replace when they lose resiliency or become
damaged. Do not paint seals or gaskets at any time.
18. For fans with a modulation inlet damper, check the linkage for binding monthly.
Dust Collector Maintenance Additional Resources
Dust Collector Maintenance Checklist
USAF has prepared this list of recommended preventative maintenance checks that can provide a better operating system with less overall maintenance and increased up-time. The frequency is only a recommendation. You may wish to increase or decrease the frequency.
Dust Collector Start-Up Checklist
Looking to start up your collector after an extended shutdown? Follow these steps to make sure your systems starts safely.
Dust Collector Maintenance Item Action Checklist
Record maintenance issues you’ve encountered during your inspection that require attention below. Note the issue, part type, part number, and quantity impacted.
Hi, this is Bob with US air filtration. And today I’m going to show you how to change out the diaphragm inside a solenoid pulse valve.
Pulse Valve Types
As you can see here pulse valves come in a lot of different sizes and shapes. Some valves have coils on the top, and some don’t. Pulse valves can have two diaphragms or one. Others have couplings, threads, or flange connectors. But the process of changing out the diaphragm is really very similar in all of them.
First Steps to Replacing a Diaphragm Valve
I’m going to show you today, on this particular valve, how to change out the diaphragm.
First thing that we’re going to do is remove the bolts that are holding on the top of the belt. I’m using a socket set and I’m going to loosen these up. Once I get all the valves loose I can pull off the top.
I’ll tell you, sometimes when these valves have been sitting, especially out in the sun for a while getting this top piece off isn’t really easy. You may need to take a screwdriver and a hammer and just tap it lightly there where the rubber is to help get the top off.
But once you get the top off you can remove the spring and you can peel off the diaphragm.
Diaphragm Valve Bleed Hole / Pin
Now in some pulse valves, well in all pulse valves, there’s a little bleed hole. And often times, there’s a pin this particular one, has a little pin right here that this allows the air pressure to equalize between the two halves of the valve.
It’s really important that we don’t block this hole or damage this pin when we put the valve back together.
New Diaphragm
Once we pull off the old diaphragm kit, we can grab the new diaphragm. And the first thing we want to do is find out where that bleed hole is in the diaphragm. Here, it’s this hole right here. We’re gonna place that right over the pin.
The teflon disc or it’s a rubber disc on your diaphragm goes down so that it seats up against this part of the valve. It’s not a bad idea to look and make sure that there’s no damage to the the body of the valve.
Typically though these aluminum bodies; it’s really hard to damage them. I don’t usually see problems with them. It’s usually the diaphragms that go.
We’re gonna line up the hole with the bleed hole. And make sure our holes line up and put our diaphragm back then.
Then we need to make sure that we have the spring that comes with the repair kit that goes back on top of the diaphragm and then we’re gonna put the top back on.
Now just like I mentioned, with this bleed hole, there’s a place where the bleed hole on this top cover goes. We need to make sure we’ve lined that bleed hole up with the bleed hole here.
If we block it, the valve is not gonna work. Or if you don’t put it on correctly, and there’s a pin, you’ll squash the pin. And then you’re gonna have to buy a new valve just to replace this little pin.
We’re gonna line this up. And I can kind of feel it set on the right. And then we’re just going to tighten down all the bolts.
Tighten Bolts
Now once I get everything finger tightened I want to go ahead and tighten these bolts down.
If I don’t tighten the bolts down properly, and you don’t get this clamping this diaphragm together, you’re gonna get a leak outside of the valve.
The best practice is, with your ratchet, is to tighten the bolt on one side and then go to the opposite side and tighten it down. And then just keep going about 180 degrees so that your getting a nice even pressure.
Upper Smaller Diaphragm
Okay now we need to do the little diaphragm.
I’m gonna pull off this coil, which I could have done before. And actually if you have electrical wires connected to this, it helps to pull off the coil.
I might add too, before you start this you need to turn off the compressed air to your valve. Or as soon as you start releasing this, it’ll just start blowing everywhere
Okay. So to change out this upper smaller diaphragm we need to loosen up these four bolts here with an allen wrench.
I’m going to loosen all of these up and then remove these bolts.
Okay once all the bolts are loose, you can lift off the top. Once again, there’s a spring and the diaphragm. You’ll grab the new diaphragm with the little metal side down.
Again there’s a little tiny pin right there for the bleed hole. Every diaphragm is gonna have a bleed hole somewhere that you need to make sure you line up.
There are a few types of valves that the bleed hole is actually in the body of the diaphragm.
In those cases you don’t have to worry about it too much. But a lot of valves have these pins.
So, I’m gonna line this bleed hole up and put it on. And take the new spring and put it on. And then I’m going to make sure that my hole right under here, where the bleed hole goes, is gonna go right over that bleed hole.
I can feel it seat down on there. And again I’m gonna tighten the bolts.
Everything’s good and tight. Put our coil back on.
And now we’re ready to turn the compressed air back on, and test our valve to make sure it all works.
Your dust collector is a major investment. Maintaining your system’s vital components is going to play a critical role in keeping your production down time and maintenance costs to a minimum. To help you determine if your filters are compromised and it’s time for a dust collector change out, check out our brief video below.
Are you ready to change out your dust collector? Download this check list below.
Hi, I’m Bob from U.S. Air Filtration. Today, I would like to answer a common question that we are often asked. That is, “When is it time to change my filters?”
There are several key indicators and considerations that will help you determine the answer to this question.
Before we discuss these, let’s review the two main reasons for changing filters. One, either the filter fabric has become compromised by a hole or tear in the fabric which now allows dust to pass through. Or two, the filter fabric has become fully entrained or clogged with dust particles which permanently restrict air flow through the filters.
Dust Collector Change Out Indicators
Ok, Let’s talk about the indicators:
This may seem obvious, but the first indicator is if you see dust coming out of the clean side of the collector. This means you likely have either a hole in the filter or the filter’s seal has been compromised.
You can find bad filters by conducting a visual inspection. Sometimes the holes may be very small or hard to find. In these situations, you can find the leak by conducting a leak test.
This is accomplished by introducing leak powder into the system. The powder will concentrate around any leaks and become visible under a black light. Call us to learn more how this product works.
Differential Pressure
While damaged filters with holes or a poor seal will leak dust, clogged filters do not leak dust. Instead the dust becomes embedded into the fibers of the filter. This increases the resistance of the air flow, which increases the differential pressure reading on your dust collector.
Differential Pressure is the difference in air pressure between the clean and dirty sides of a collector.
A consistently higher differential pressure indicates that it is more difficult for the air to get through the filter media and usually means filters are nearing the end of their life span.
When you consistently see Differential pressure readings of 6 or above and they don’t drop significantly during the collectors cleaning cycle, it’s generally a sign that it’s time to change your filters.
Loss of Suction at Pick Up Points
Another indicator that points toward a filter change-out is when your pick up points are not getting the suction you’re used to seeing. It is the permanently entrained dust that causes the reduced air flow, and as we mentioned, the higher differential pressure.
Dust Collector Change Out General Rules
Let’s discuss a few other considerations.
As a general rule, it is better to change out all the filters in a collector than a few at a time. Air flow always follows the path of least resistance, and you can quickly wear out new filters if they are doing all the work in your collector.
Some of our clients like to change out filters during scheduled plant shut downs or on a maintenance schedule.
Filters may have some life left, but this is a good option if the risk of having a problem before a scheduled shut down is too great, or the predictability of filter life is fairly certain.
Laboratory Tests
One final thing to consider is using a laboratory test to determine how much life remains in a set a filters. This testing is not common and is typically only when the bag cost is substantial and there is a lack of history with the bag life or there is some other unique problem that can’t be otherwise solved. In most cases, the other mentioned indicators are sufficient to determine when to change out your filters.
How Long Filters Last
Another question we are often asked is how long do filters typically last.
This is a really tough question to answer because there are so many environmental factors that come in to play. We have seen filters last anywhere from a few weeks up to 5 years or more. On average, life expectancy is about a year, but it really varies.
Here is a list of some of the factors that influence filter life. To find out more about these factors or to ask one of our experts if it’s the right time for a dust collector change out, give us a call.
A well maintained dust collector ensures your system is performing at peak efficiency. It’s also critical to minimizing unscheduled plant downtime and the wear and tear of your dust collector parts. As part of a regular preventative maintenance program, customers can also request a visit from bonded and insured technicians to perform either a dust collector inspection. An inspection typically includes an analysis of your dust collector and its most vital parts, a written report, and recommended corrective actions to solve any issues. An inspection may also include an exam of the following:
Overall status of dust collector(s)
Compressed air system for leaks
Regulator pressure
Air Shut off valve is sealed and is properly working
Different from an inspection, a service on a dust collector system includes bonded and insured technicians performing a change out or corrective actions. This can include the following:
Repair or replace damaged solenoids, valves, or diaphragm kits
Any other repairs or troubleshooting needed on a baghouse – for example, vibration issues with a system after a filter change
Dust Collector Inspection and Service Questions
If you are looking for an inspection or service from a supplier, here are some of the most common questions asked before receiving a formal proposal and costs.
What type of service or troubleshooting are you requesting?
Where will the service take place?
What type of dust are you filtering? Is it hazardous? Is special safety equipment required?
Are there any current issues with your filters?
Is there any special training or background checks needed before entering a facility?
When would you like to have the service performed? What are the permitted service hours (evening or day work, weekends only, etc.)?
For more information on inspections or services for your dust collector, you can contact a USAF account manager at 888-221-0312 or also email [email protected] Also included below is a link to our comprehensive dust collector maintenance eBook that can be downloaded.
For a little Christmas Cheer we’ve pulled together some of our most popular dust collection maintenance resources here to the theme of the 12 Days of Dust-mas. Enjoy!
Is your building all dusty? Time for a new system? Check out a 3D Demo of our most popular baghouse units.
Two broken bags? Check out this video on how to detect a dust collector leak in your system.
Is it time for a changeout? Here’s a brief instructional video on how to changeout your USAF cartridge filters.
Do you have a leaky diaphragm valve? Get some tips you can try to troubleshoot your broken valves.
Is your differential pressure rising and dust escaping your dust collector? It could be blinding bags. Find out how to tell your bags are compromised and signs it’s time for a filter changeout.
Having trouble removing dust from your dust collector? Has your dust load increased? Check out some of the most common dust removal options available including rotary valves and pneumatic conveying.
Need help installing pleated filters? Here’s a brief tutorial on how to install yours correctly.
Do you have clogged bags? Does your system utilize on-demand cleaning? Find out how this can help you save time and energy.
Are you looking to expand plant operations in the new year? Get information on how much a new baghouse, cartridge collector or bin vent costs and all the factors that go into the cost of a new dust collection system.
Check out our USAF Cartridge Dust Collector 3D Demo and learn how a USAF system can help improve plant operations.
Performing maintenance or troubleshooting inside your baghouse can be dangerous. Here are some basic baghouse entry procedures you can implement to minimize accidents and hazards.
Power Down & Lock Out
Before you begin any maintenance or troubleshooting on your dust collection system, your first and most important step is to power down and lockout any machinery. Securing your baghouse for personnel entry can include locking down your rotary valve, locking your blower, or sealing off any adjacent baghouse compartments.
Also, make sure to shut off the compressed air supply to the pulse jet cleaning system and allow the system to cycle until the pressure is relieved before entering the baghouse. Taking these initial steps provides a safe working environment and will ensure that accidents are minimized.
Safety in a Confined Space
The inside of your dust collection system is almost always defined as a “confined space”. No matter the application, it’s best to ensure you have safety guidelines in place whenever entry into your baghouse needs to occur. Here are some of the general safety precautions you can take.
Additional Watchman
Designate an additional crew member as a watchman. They should be present at the entrance point to ensure safety procedures are being followed and can immediately assist should any complications occur.
Communication
It’s important to let your team know what work is being done, where, and at what time. This allows others to re-schedule any work that could impede on safe entry into your baghouse.
Combustible Dust
If you are working with combustible dust, make sure the dust levels inside of your system are well below being explosive. All hot work, like welding, should be performed well outside of the perimeter of your baghouse. If hot work must be done inside the baghouse, thoroughly purge the space with clean air until dust is no longer present.
Emergency Plan
A total shut down and lock out of your baghouse will minimize safety hazards, but you shouldn’t hesitate to formulate a retrieval plan should an emergency occur while employees are in inside the confined space.
PPE Personal Protective Equipment
OSHA requirements for protective gear will vary based on your application. Basic protection can include a hard hat, safety glasses, gloves, and a face mask. Before entry into your baghouse system, make sure that your crew is supplied with and compliant in wearing safety gear required for your application. You can find additional information on OSHA’s website about personal protection equipment hazards and solutions https://www.osha.gov/SLTC/personalprotectiveequipment/hazards_solutions.html
As local, state, and federal governments begin to relax social distancing guidelines in the days, weeks, and months ahead, many non-essential factories and industrial plants are anxiously looking to resume production. Employers are also now faced with the responsibility to minimize the risk of spreading COVID-19 by instituting new safety measures.
Taking proactive steps now to implement new health measures and make sure your dust collection equipment is operating properly will protect the safety and health of your workforce first and foremost. These steps will also ensure your system is in good working order so you don’t have to worry about another unexpected shutdown.
To help streamline this process and make your start-up as hassle-free as possible, we have prepared a comprehensive checklist, and action item notebook. These resources can help you address any issues promptly. Our guide is broken out into these following sections:
COVID-19 Management Best Practices for Manufacturers
Dust Collector Start-Up Checklist
Action Item Checklist
Maintenance Questions to Consider
To get started you can download the complete return to work PDF guide by clicking below.
Our start-up check list can also be printed, completed electronically in the PDF file, or you can access the checklist on your phone or mobile device by clicking below.
For additional dust collection maintenance resources and troubleshooting advice to help you get online again safely, visit our YouTube channel. Follow us on Twitter,Facebook and LinkedIn to get access to additional resources and tips on dust collection design, safety, case studies and more.
Differential pressure is a critical tool to make sure your dust collector is operating properly. In this video, we’ll answer these top questions about differential pressure and how to use differential pressure to keep your dust collector at peak performance.
Top Questions about Differential Pressure
What is differential pressure?
How does differential pressure work?
How can I use it to better maintain my dust collector?
What do sudden changes in differential pressure mean?
My differential pressure reading is high. What can I do to fix it?
My differential pressure reading is low. What can I do to fix it?
What differential pressure should my dust collector be at?
Video Transcript:
Hi this is Bob from US Air Filtration.
Differential pressure is a great tool that you can use to make sure your dust collector is operating properly.
Today we’re going to talk about what differential pressure is how it works. And how you can use it to better maintain your dust collector.
Differential pressure commonly called DP, measures the difference in pressure between the clean and dirty sides of the collector.
As dust builds up on the filters it creates more resistance for the air trying to pass through. This creates unequal pressure on each side of the filter. The dirtier the filters become the more unequal the pressure gets. Resulting in the higher DP reading.
To illustrate this concept let me compare it to something we’re all familiar with; drinking from a straw. If I drink this soda through a regular soda straw I can get a fair amount of liquid with not much effort. However if I try to drink soda through a small little coffee straw it takes a lot more effort and I get a lot less volume through the straw.
The same thing is happening in your dust collector. As the filters get dirty, the holes that allow air to pass through get smaller and smaller causing the differential pressure to rise.
Once your dust collector’s cleaning cycle has taken effect then the dust is released. It opens up those pores and allows air to flow through. And your differential pressure will drop.
Differential pressure is measured by a gauge with the fancy name called a manometer. This gauge is usually part of the dust collectors control panel. Air tubes from the clean and dirty sides of the collector are brought into the control panel and connected to the port’s on the gauge. The gauge can either be analog or digital. In either case the gauges typically report the DP in a measurement called inches of water or sometimes called water column.
Since every dust collection system is different DP readings are relative and should be compared to the collectors baseline levels.
A collector with brand new filters usually sees a DP reading of one to two inches. As filters age and become more entrained with dust the differential pressure levels over time. Near the end of the filters life the DP will be around six inches and stay there even after the cleaning cycle has run.
Running a collector consistently above six is not recommended since it will likely cause a noticeable drop in plant suction and lead to faster dust entrainment and shorter filter life.
Sudden changes in DP can indicate problems in the collector when the differential pressure becomes suddenly low. It means there is no resistance to the filter because of the presence of holes or poor seals. DP that suddenly becomes high means the filters are plugged, which could be due to problems in the cleaning cycle. Usually a
bad diaphragm or solenoid valve is the culprit.
For more information on differential pressure or to have one of our representatives help you understand what differential pressure is telling you on your collector, give us a call today.
Emergency Plan
