The past few years have been a roller coaster for the global supply chain, with natural disasters and pandemics causing major disruptions for manufacturers. These challenges directly impact manufacturers’ ability to effectively run production and positively impact the supply chain downstream.
In this article and latest “Filtered: On the Air” podcast episode, our experts Tim Keeter and Brent Bassett discuss supply chain issues and its impact on the dust collection industry, while also providing tips on how to alleviate some of the issues that manufacturers face in today’s supply chain.
The Future of the Supply Chain Delays
No industry was immune to global supply chain delays that have been impacting manufacturers the last few years. While some sectors did bounce back quickly, others are still in the process of recovering. Looking ahead, most of us learned that predicting anything has gone completely out the window. It appears things have improved, there are shorter delays, and more products on the shelves. As a result, we’re seeing less supply chain issues impacting consumers. But it’s still hard to tell as there are places around the world that are still recovering. At U.S. Air Filtration, we like to hope for the best but prepare for the worst. One takeaway from the last few years is that we can all be better prepared.
Industry Purchasing Trends
There are customers who have storage space, which has allowed them to update their purchasing process to include a back-up set of filters. More commonly, we see customers who try to order a month or two sooner than they normally would. But that may not always work out because some parts can have multiple delays. While an order may originally have a lead time of two months, there could be an additional delay for another month. One example would be for cartridge filters which consist of multiple parts. All it takes is one of those crucial parts of a cartridge filter to have a delay, and as a result the entire filter is delayed. In this scenario, planning ahead doesn’t always guarantee you’re going to receive your items on time.
How To Reduce Supply Chain Delays
Having a solid preventative maintenance plan is key. If you’re organized with your change outs, and know when they’re going to happen then you can order your things well in advance. One thing that U.S. Air Filtration can do for our longtime customers is help them realize their normal buying patterns. Oftentimes people just don’t know what those patterns may be. But if a customer has been ordering from U.S. Air Filtration for a number of years, we can look at those frequencies whether it’s every 12 months, or every 9 months which allows us to suggest a time to order with a little bit of a cushion.
In summary, a maintenance plan reduces the supply chain challenge because it allows a manufacturer to develop a predictable pattern, and understand the intricacies of their production. Some plants absolutely cannot run when filters clog, which means all production may stop if there is no cushion when ordering dust collector wearables. If you’re one of those clients that is going to shut down without your filters running at peak performance then you need to be able to plan ahead.
Some of the warning signs to look out for include a rising or high differential pressure. If your differential pressure is rising, your filters are getting clogged. If you know how often this happens, then maybe your filters typically last a year. This shows that your normal production schedule is pretty consistent and you could just order a few filters at a time. Knowing when that happens is key. But a lot of facilities will have a tough time because their production may change. They may run 24/7 for a couple of months on a big project and then slow down for a couple of months. So it’s a little less predictable for some people.
Due to the lack of predictability within manufacturing in general, some facilities opt to purchase a back-up set of dust collection parts. While some manufacturers are safe from unscheduled downtime with the availability of back-up dust collection parts, there are still a lot of companies out there that just aren’t equipped to store them. Another factor could be budget and timing.
Having a spare set of filters is always something the U.S. Air Filtration recommends, but we understand that there are challenges that come with this besides the storage issue. Here’s a few considerations with having to store dust collector filters
Contaminants or pests
There are a lot of considerations to make when you’re thinking about storing,100 filters versus 1000 filters. But, at US air filtration we have come up with a solution on how to solve these issues.
STOCK ‘N GO Program Solution
At U.S. Air Filtration we have developed the STOCK ‘N GO program to address most issues that companies are challenged with when stocking extra parts. How it works is, U.S. Air Filtration will fabricate filters ahead of time for customers and store them in our warehouse. This way when a customer is ready for them, we can ship them out just within a day or two of being notified. This takes away the stress and the headache from the ordering process and lead times, resulting in a streamlined purchasing process.
In summary, supply chain issues can have a significant impact within the industrial air filtration industry resulting in delayed lead times passed down to manufacturers. Implementing a maintenance program and having a set-up back of dust collection parts are our top tips to alleviate the challenges that manufacturers face in today’s supply chain environment.
At US Air Filtration, we understand the importance of reducing supply chain delays. We are here to help ensure that your dust collection systems are working at optimal levels, so you can focus on growing your business and meeting the needs of your customers. If you would like more information about the STOCK ‘N GO program, visit us here. You can also reach out at 888-221-0312 or email [email protected]
To download a free PDF version of this Dust Collector Filter Bags Guide simply click this link here.
Choosing the right filter bags for your dust collection system is critical to ensuring long term, reliable performance of your collector and the safety of your employees. Our guide will help you understand your facility’s unique dust properties and provide an overview of various filter media, construction, and treatment options available.
We’ve organized our dust collector filter bags guide into these key topics:
Top Factors to Consider for Dust Collector Filter Bags
Understanding Your Dust Properties
Common Filter Media
Filter Bag Finishes
Filter Bag Construction
Understanding Dust Properties
Choosing the right filter media for your dust collection system is critical to achieving peak performance while reducing system wear, plant downtime, and extending filter life. The first step is to consider the properties of your dust particulate and review the following:
Product – What you are filtering? Does your product contain a moisture or oil? Products with moisture content greater than 25% are not suited for a dry dust collection system (baghouse, cartridge collector or bin vent). Products containing hydrocarbons, including oils, may require the application of special treatment to your filter media for optimal
Temperature – What is your typical operating temperature? Max temp? Media temperature ranges for dry dust collection can typically be sorted into three categories listed below:
< 275°F – Polyester filter media performs very well for ambient airflow temperatures in this range.
Between 275°F and 400°F – Aramid filter media is the optimal choice for temperatures in this
Between 400°F – 500°F – Fiberglass filter media is the most economical option for high-temperature applications; however depending on the type of dust, another filter media may be a better
Once you understand the temperature of your work environment, you can narrow down your filter media options and in many cases, apply a special treatment to the media to further improve performance. Treatment application can be an efficient way to minimize costs before considering a more expensive filter media.
Does the airstream or dust contain chemicals that could damage the filter media? Are their acids or alkalines in the airstream? Often when certain compounds are combined during processing, a chemical reaction can occur, which may require a specific media treatment or coating on your filter bags to protect the bags from accelerated wear.
How abrasive is the dust being filtered? Consider the hardness of the material that’s being filtered along with the shape of the dust. The velocity of your airflow can also make your dust more abrasive. If you are designing a new dust collection system, it’s important to engineer the ductwork, fan size, and unit placement to ensure the airstream is not entering your dust collector too quickly or too slowly.
What size dust particulate are you collecting? Depending on your emissions requirements, your application may require a special membrane. This will apply if your particulate is very fine.
Is Your Dust Combustible?
Combustible dust can be defined as any fine material that has the ability to catch fire and explode when mixed with the proper concentration of air. Examples of combustible dust include wood , food products such as grain, sugar, flour, starch, metals, rubber, chemicals, pesticides, plastics, and more. To protect your plant and your employees from the risks of a serious explosion, carefully consider OSHA and NFPA guidelines and be sure to review your state and local regulations for proper identification and management of combustible dust.
Implement and maintain OSHA’s set of standards regarding combustible dust. When you adhere to OSHA’s set of standards, you are creating a safe work environment, avoiding property and economic loss from an explosion, and avoiding regulatory fines.
Make sure you are meeting codes outlined by the NFPA (NationalFire Protection Agency) . The NFPA publishes a list of guidelines that will help you minimize injury or death from combustible dust. The following regulatory codes are related to the most combustible types of dust (e.g., sugar, wood , fine aluminum):
664, Standard for the Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities
484, Standard for Combustible Metals
61, Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities
Dust testing may also be performed to assess the properties of your particulate and ensure proper filter selection and performance. This option may be ideal for new facilities and large applications . If you have an existing plant and many of your filter bags have failed prematurely with no consistent pattern, and there are no signs of workmanship error, it may be necessary to perform laboratory testing to find out if changes in the airstream could be compromising the bags.
Common Filter Media
Polyester media is an economical option with excellent filtration properties and is widely available. This makes polyester the most common filter media used across many industry applications. Polyester has an operating temperature limit of 275°F and comes in both needled felt and woven medias. Both needled felt and woven polyester can be treated with several finishes and membranes to increase the efficiency and filter bag performance in varying operating conditions.
Aramid, also known as Nomex, is used in applications with high temperatures and has excellent filtration and abrasion properties. The operating temperature limit for aramid is 400F which makes it a great choice for applications such as asphalt batch plants, furnaces, and dryers. Both needled felt and woven aramid can be treated with several finishes and membranes to increase the efficiency and filter bag performance in varying operating conditions.
Fiberglass is often used in baghouses with temperatures ranging up to 500°F. Since fiberglass media is typically woven, the efficiency of a plain fiberglass media is lower than most felts. However there are several different membranes and finishes that can be added to fiberglass to increase filter efficiency and performance in harsh baghouse conditions. These finishes and membranes make fiberglass a versatile media for applications with high temperatures. You’ll see Fiberglass media used in industries such as energy, cement/ concrete/aggregates, and agriculture. Different membranes, coatings and finishes can be added to fiberglass media to increase performance in certain applications. This makes fiberglass a versatile media for applications with high temperatures.
P84 media has a high temperature rating of up to 500°F. This filter media handles acids better than fiberglass and also results in less abrasion to the filters due to filter media flex.
Teflon (PTFE) is one of the highest performing filter medias available for a wide range of applications and is also the most expensive. It bears well against chemical and acid resistance, high temperatures, and moist heat. Teflon membrane can also be applied as a treatment on other filter medias to further extend filter life and reduce system wear.
For more information on other media types in the dust collector industry (e.g. PPS, Acrylic, and Polypropylene) access our Fabric Characteristics Chart below.
Filter media fabrics can be made from both natural and synthetic fibers, although synthetic fibers are more common today. As we have seen in the previous section, different fibers provide each media with different performance characteristics. Most medias today are pre-shrunk and include some type of finish to improve media performance. Finishes for felt and woven bags can be different as we will see below.
This process is the scraping of the filter surface across metal points or burrs on a revolving cylinder. Napping raises the surface fibers, creating a “fuzz”, that provides a large number of sites for particle collection by interception and diffusion. Fabrics used for collecting sticky or oily dusts are sometimes napped so they can provide better collection and an easier cleaning process.
Coatings , or resin treating , involves immersing the filter material in a resin which can add certain characteristics to the filter media. For example, fiberglass threads can be coated with Teflon to prevent abrasion during bag cleaning and silicon graphite to aid in acid resistance.
In each baghouse style there are a variety of filter top and bottom configurations that can be used. Some top and bottom configurations are meant for a specific baghouse style, and other configurations can be used across multiple baghouse styles.
Pulse jet baghouses collect dust on the outside of the filter and clean filters from the inside out with a jet or pulse of clean air. Dirty air enters the baghouse and is forced to pass through the filter bags to exit the baghouse. As air pass through the bags, dust is filtered out and collects on the outside surface of the filter bags. This buildup of dust on the outside of the filters is known as a “filter cake.” The filter cake aids in filtration by trapping smaller particles as the dirty air passes through the filter cake and bag. Pulse jet baghouses offer a wide range of filter media, making it an excellent fit for most applications.
Reverse-Air or Shaker
In a baghouse using reverse air or shaker cleaning systems, the particulate is collected on the inside surface of the bag. The dust-laden gas enters the dirty side (inlet) of the collector and flows up through the bag. The particulate is filtered by the dustcake and the fabric, and clean air exits through the outside of the bag. Shaker and reverse air bag top and bottom designs vary by cleaning system and original equipment manufacturer.
Reverse air and shaker style baghouse both collect dust on the inside of the filter bag. Reverse air baghouses reverse the flow of air through the baghouse in order to clean the filter bags while shaker style baghouses clean the filter bags by moving them back and forth in a shaking motion. The buildup of a filter cake is important with these style collectors as it greatly aids in filter efficiency.
Both pulse jet and reverse air/shaker style baghouse come in a number of different bag constructions and understanding the requirements of your specific baghouse is important to ensure proper filter bag fit.
Dust collector air-to-cloth ratio is a critical measure to ensure your collector is performing efficiently.
Air-to-cloth ratio, also known as air to media ratio, is a measurement of the number of cubic feet per minute of air passing through one square foot of filter media.
Generally, a lower air-to-cloth ratio, the more effective your system is at removing dust from the work environment. When determining an appropriate air-to-cloth ratio, there are several factors to consider, including application, type of dust, moisture levels, inlet loading, etc. If the air-to-cloth ratio is higher than recommended, some common issues can arise, including increased differential pressure, frequent filter changeouts, and varying or reduced suction at pickup points. These issues are a result of not having enough filter media to handle the air flow and dust load effectively. As the dust cake builds on the filters, the airflow is restricted and slows, resulting in a decrease in air velocity and suction. From there it becomes a domino effect: air quality decreases, filters clog quicker requiring more changeouts, pulse valves see increased wear, and facility production may be impacted.
Why is the right Air-to-Cloth ratio important?
Ensures dust collector is running efficiently
Minimizes operating costs
Maximizes filter life
To meet air quality goals and requirements
What are the negative effects of an improper Air-to-Cloth ratio?
Increases maintenance which can impact production
Reduced air velocity resulting in poor ventilation at pickup points
Download the chart below for a summary of recommended Air-to-Cloth ratio for a variety of industrial applications.
Dust Collector Filter Bags Additional Resources
Filter Bag Media Quiz
Finding the right filter bag can be overwhelming, confusing and time consuming. There are so many options and it’s hard to know which will work best for your application. Or if there is a better option out there that will get you better performance.
To get you to the right solution, take this interactive filter media quiz. You’ll immediately receive:
Recommendations on the best filter media options for your unique application.
Filter media characteristics chart with media specs and pricing.
No obligation price quote for your filter media within 24 hours.
Selecting the right dust collector filter bags will keep your employees and your operation safe and at peak performance. We hope this information is a helpful resource for you. For tips and troubleshooting guides, check out our article on dust collector maintenance.
If you have specific questions about your application and filtration needs, call today at 888-221-0312 or email us at [email protected]One of our dust collection specialists can assist you with your dust control challenges. If you have an upcoming dust collection project and need assistance, read Dust Collector Purchasing Guide or contact one of our equipment specialists at the number above.
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
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.
No power to the timer board
Pulse valve not pulsing
Pulse valve leaking air due to small electrical charge coming from timer board
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
Pulse valve is leaking air
Filter bags not being cleaned, increased differential pressure
Is your spring broken?
Leaking air even after replacing diaphragm kit and checking solenoid and timer board
Stripped or damaged threads
Cracking on valve housing
Pulse is weak
Filters aren’t cleaning properly
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
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
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.
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.
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
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.
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.
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.
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
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
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
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
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.
Unfortunately, shipments from any dust collection supplier you work with can sustain damage during transit. While you cannot control what happens in-transit, you can control how you respond to freight that arrives damaged.
How Damaged Freight Affects Your Bottom Line
Shipping claims and getting replacements for damaged freight can be a frustrating to deal with, but the true price tag of this issue can cost far greater than just a few broken boxes or lost product. Other costs to your business may include:
The U.S. Air Filtration logistics team understands that packaging can play a role in the potential of damaged freight. Your shipment will be handled by many people along the way. So we keep this in mind when we prepare your dust collection order for shipment in the U.S. Air Filtration warehouse, and we follow a system of best practices that can help protect your items as much as possible.
Inspection –To avoid shortages we inspect, count, and match up the items to your packing slip.
Right Packaging – Our team makes sure that the box is suitable for the item that is shipping.
Proper Seals – We distribute tape evenly to ensure your product stays fully sealed in its package. For palletized items, we shrink wrap your freight multiple times to ensure all boxes remains together.
Appropriately Sized Pallets – Our warehouse team makes certain that the right sized pallet, also known as a skid, is the right one for the weight and size of the shipment.
Clear Shipping Labels – Labels are legible and durable. Paperwork such as a bill of lading or packing slips are placed inside of a protective sleeve.
How Do I Receive Freight?
There is one golden rule of receiving freight that every receiving dock should follow. Do not accept or sign the bill of lading before checking freight for damage, concealed damage, or missing parts.
It’s critical to pay close attention and inspect all details when you receive a freight shipment. You have the right to record exactly what is missing or damaged. If damaged freight is not recorded, you may not be able to file a successful freight claim.
When you receive freight, here are the steps you should take.
Box Count & Damage Inspection
Count the number of boxes received. Compare the box count to the bill of lading for accuracy.
Inspect the shipment for any visible damages. Ensure all packages are consistent.
Are there any damages present? If yes, then take immediate action with the following steps.
Accept the shipment as damaged.
Write down all damages or missing box count on the delivery slip.
Take photos to showcase the condition of goods when received.
TIP: Do not refuse a shipment or discard any damaged freight. Your shipment may get damaged further, or worse, lost in storage. Without your dust collection products in-hand, getting replacements or a freight claim solved can take several weeks longer.
TIP: Keep a copy of all related documents like the bill of lading, packing slip, and copy of your invoice.
TIP: There is a limited window of time to submit a freight claim for resolution.
Report any damages to your supplier within 24 hours of receiving your shipment and they will help your take the next steps. If your shipment was from U.S. Air Filtration here is what you can do:
Contact your account manager directly or the USAF main line at 1-888-221-0312.
Send all photo evidence and a copy of the delivery slip to USAF.
USAF will help start the freight claim process and get you replacements ASAP.
Damaged freight is a headache that no one wants to deal with. They strain your time and bottom line. If you would like to get help with your damaged shipment, submit your information with our interactive receiving checklist below. Once your information is received, a U.S. Air Filtration rep will be in touch to help.
Shaker baghouses collect dust similar to reverse air baghouses. Dust collects on the inside surface of the shaker filter bags, and then clean air exits through the top of the bag. The main difference is how the bags cleaned.
How to Clean Shaker Filter Bags
Shaker baghouses are engineered so that filters are hung and tensioned from the top of the unit, and at the bottom they are attached to a tube sheet. Mechanically shaking the filter bags is what cleans them. Shaker baghouses only clean while the system is off-line. Shaker baghouse operation is simple and can be seen in applications where no compressed air is available.
Construction of Shaker Filter Bags
Fabric filter bags used in shaker baghouses are typically constructed with woven or light weight media options like polyester sateen, shaker felt, beane knit, and more. Treatments are dependent on a plant’s application and dust characteristics. The most common top and bottom configurations for shaker baghouses are below.
Most Common Top & Bottom Construction for a Shaker Baghouse
Top Load Baghouse: Grommet Top, Loop Top, Strap Top Bottom Load Baghouse: Corded Cuff Bottom, Double Beaded Snap Band
If you would like to get a free media recommendation, check out our filter bag media quiz here. There is also a fabric characteristics sheet that you can download below. It takes a closer look at the most common filter bag medias used in the dust collection industry.
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.
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.
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.
Pulse-jet filter bags are used to remove dust particulate and contaminants from the air in warehouses, plants, factories, foundries, and more. Pulse-jet is one of the most common styles of baghouses you will see across a variety of industries and applications. With this style of baghouse, dust collects on the outside of the filter as clean air exits through the inside of the bag.
How Pulse-Jet Filter Bags are Cleaned
To clean pulse-jet baghouse filters, a blast of compressed air is injected through a blowpipe over each row of bags via a venturi. In a pulse-jet baghouse one row of bags can be cleaned while the remaining rows continue to collect dust particulate. This is known as on-line cleaning.
Construction of Pulse-Jet Filter Bags
Pulse-Jet baghouses are engineered to hold either bottom or top load filter bags and cages. Fabric filter bags used in pulse-jet and plenum pulse baghouses come in a variety of medias and treatments. The type of filter media and treatment that’s best will be dependent on a plant’s application and dust characteristics. To get a free filter recommendation, check out our filter bag media quiz here. You can also download our fabric characteristics sheet to get a closer look at the most common filter bag medias used in the dust collection industry.
Most Common Top & Bottom Construction for a Pulse-Jet Baghouse
Top Load Baghouse: Double Beaded Snap Band Top, Disc Bottom Bottom Load Baghouse: Raw Top, Disc Bottom
Is your application operating at a high temperature over 275 degrees Fahrenheit? If so, there are many dust collector filter bag options to choose from. Outlined below is your guide to high temperature dust collector filter bags. We’ve broken down characteristics and properties of the top five most common filter media options.
Aramid filter media is commonly used in asphalt plants and rock plants where there is high heat but are no chemical issues. You can typically distinguish an Aramid filter bag by its color. It is usually yellow and can have brown speckles which is caused by singeing.
Aramid (Nomex) Filter Bag Media
Max Continuous Operating Temperature
400 Degrees F.
Provides great resistance to highly abrasive dust applications.
Mineral oxides can cause deterioration or partial decomposition over time.
High Temp Dryers
Fiberglass filter media has been the leading industry standard for dust collection applications where high temperatures above 500 degrees Fahrenheit are present. Fiberglass filter media is composed of a dense structure of fine fiberglass filaments. You’ll see Fiberglass used in industries such as energy, chemicals, and minerals.
It is cost efficient when compared to similar high heat filter medias and is the most common choice for situations where heat is above 400 degrees Fahrenheit. Fiberglass can have a lot of variation in color, and depending on the application, can have different types of treatment (i.e. silicon, carbon).
Fiberglass Filter Bag Media
Max Continuous Operating Temperature
500 Degrees F.
Performs excellent in high temperature applications up to 500 Degrees Fahrenheit.
Sensitive bag to cage fit. Has poor flex abrasion qualities and would require a cage with 20 vertical wires for minimum support.
P84 (polymide) dust collector filter media is used in operating conditions of a maximum 500 degrees Fahrenheit. P84 performs well under dry high heat temperatures and can even withstand some elevated levels of moisture. P84 has a slightly better resistance to acids than PPS. This is a proprietary fabric that is imported from Germany to all manufacturers. For these reasons, P84 is one of the more expensive filter medias used in pulse jet baghouse dust collectors. P84 filter can be seen in used in waste to energy, power, lime kilns, smelting, glass and ceramic, and cement applications.
P84 Filter Bag Media
Max Continuous Operating Temperature
500 Degrees F.
Excellent stability in applications with high dry heat temperatures, mineral acids, and alkaline.
Must oversize bag for shrinkage that can occur in temperatures above 450 Degrees F.
Teflon delivers superior dust cake release and high filtration efficiency in high heat applications that demand high resistance to acids and moist heat.
Must oversize bag for shrinkage that can occur in temperatures above 450 Degrees F.
Coal Fired Power Plants
Carbon Black Plants
Do you need more information after reading this guide to high temperature dust collector filter bags? If you need help, one of our account managers can help find the right fit for you. Contact us at 888-221-0312, email [email protected] or request a consultation here.
Today we are exploring the differences between Polyester vs Polypropylene filter bags. Polyester is one of the most widely used filter bag medias in the dust collection industry because of its reliable performance in a broad range of applications, relatively low cost, and availability. Many industries including food manufacturing, woodworking, metalworking, building products, and energy have used polyester filter bags to achieve peak dust collection performance. If you continuously operate between temperatures of ambient – 275 degrees Fahrenheit and you have less than 10% moisture in your application, then polyester may be the right fit for your application.
Polypropylene is also another relatively low-cost filter bag media. The main difference between polyester and polypropylene is how well polypropylene can withstand moisture. If your continuous operating temperatures are between ambient – 170 degrees Fahrenheit, and you have more than 10% moisture in your application, then Polypropylene could be the right fit for your baghouse.
To find out which media is the right fit for your specific application you can take our filter bag media quiz that will provide an instant recommendation based on your application.
Polyester vs Polypropylene Filter Bag Treatments and Finishes
Depending on your specific needs an additional filter bag treatment or finish could be lengthen the life of your filter bags.
Polyester Filter Bag Finishes & Treatments
PTFE Membrane – Can double the life of a standard filter bag, reduce wear and tear, reduce maintenance costs, reduce energy costs, and more.
Hydro-oleophobic coating – Aids in filtration and adds resistance to water and oils.
Acrylic – Can help improve cake release and filtration efficiency in certain applications.
Anti-static – Helps ground the filter bag.
Singed – Removes straggly fibers which provides a uniform surface area and improved dust cake release.
Glazed – Improved mechanical stability since fibers are fused to the body of the filter medium.
Calendered – Flattens and smooths the filter medium. This can increase surface life, dimensional stability, and provides a more uniform fabric surface.
If you’re looking for additional filter bag resources such as construction, air-to-cloth ratio or dust properties you can download our filter bag eBook below. You can also access our filter bag characteristics chart below.
Ready to find your filter and need a quote within 24 hours? Simply follow the link below and we’ll help with your filter bag request.
Understanding the properties of your dust particulate is a key component to choosing the right filter bag media. The right media allows you to get the best performance and longevity out of your dust collector filters. Consider the following properties and how they play a role in your filter media choice:
What is your operating temperature? What is your max temperature? If you are operating at a high temperature, you will need specific filter bag media or a special treatment to withstand the heat. Temperature ranges for dry dust collection can be typically sorted into the following categories:
-Ambient – 265 Deg F
-275-375 Deg F
-400-500 Deg F
Does your application contain dust particles that have a chemical make-up? If so, you may require a media treatment or coating that will prevent your filter bags from accelerated wear.
How abrasive is your dust? Consider the hardness of the material that is being filtered along with the shape. If it is abrasive, you will need a filter bag media with the ability to resist the additional wear and tear.
Is your dust combustible? The most combustible types of dust are dust from wood, sugar, or fine aluminum but there is a wide range of industries that operate with combustible dust.
For help finding the right filter media for your application, try our filter media quiz to get your recommended filter media.
How Air to Cloth Ratio Affects the Performance of your Filter Bags
Air-to-Cloth ratio is a measurement of the amount of air passing through one square foot of filter media. Calculating the right air-to-cloth ratio allows your dust collector system to run at peak performance, it extends filter life, minimizes operating costs, and helps you to meet air quality goals. When calculating air-to-cloth ratio for your dust collection system, keep in mind that generally the lower your air-to-cloth ratio, the more effective your system is at removing dust from the work environment. Increased differential pressure, frequent change outs, and reduced airflow due to a buildup of dust cake are just come of commonly experienced problems with a higher air-to-cloth ratio.
There are a few commonly used industrial dust collector filter bag medias used with industrial dust collectors. Polyester, Aramid, Fiberglass, P84, and PTFE are all common options that are available at different price points and have varying characteristics such as maximum operating temperature, resistance to chemicals and acids, ability to withstand abrasion and more.
Polyester is widely available at a relatively low cost. Polyester filter bag media offers great dimensional stability and has good overall qualities to resist abrasion while performing well with dry temperatures. It’s used in woodworking, manufacturing, food processing and more.
Fiberglass filter media is a leading industry standard for applications where continuous operating temperatures of 500 degrees Fahrenheit are prevalent. It’s most commonly used in industries such as chemicals, minerals, and energy pipeline and utilities.
When it comes to filter bag construction there are a wide variety of configurations. The simplest way to understand the top and bottom construction needed for your filter bag will be knowing the type of dust collector system you have. There are three common types of baghouses; pulse-jet and plenum pulse, reverse air, and shaker.
Pulse-jet and plenum pulse baghouses are the most widely used style of dust collector. They can be configured as either top load or bottom load. If your baghouse is top load the most common filter bag construction is a double beaded snap band top with a disc bottom. If you have a bottom load baghouse the most common construction is a raw top with disc bottom.
Reverse air baghouses are typically seen in large air handling applications. The most common filter bag configuration is a compression band with cap and hook for the top. For bottom configuration you will typically see either a compression band, corded, or double beaded snap band.
Shaker baghouses are generally simple and can be seen in applications where there is no compressed air available. In shaker baghouses the filter bags are hung and tensioned from the top of the unit, and at the bottom they are attached to a tube sheet. The most common top configurations are grommet top, loop top and strap top. Bottom configurations can range from corded cuff or a double beaded snap band.
To measure a bag, you need to get three critical dimensions. The first dimensions that we need to know is the snap band size. This is actually the hole size in your baghouse that the bag snaps into. We also need to know the bag body diameter. Which is the diameter of the bag, at the midsection of the bag. And we need to know the overall length.
Applying a specific finish or treatment is one way you can lengthen the life of your filter bags and achieve better performance. Whether your filter bag media is constructed of synthetic or natural fabrics, treatments such as calendering (glazing), napping, singeing, or coating are available.
One specific filter bag treatment that stands out among the rest is commonly known as Teflon or PTFE. It’s used in many different applications but when specifically laminated to a filter bag media it can enhance the performance of both the filter bag and the dust collection system.
This is also known as glazing and is done to increase and uniform surface life, improve stability and reduce shrinkage.
Fabrics used for collecting sticky or oily dusts are sometimes napped so they can provide better collection and an easier cleaning process.
This removes any straggly surface fibers and results in a more uniform filter bag surface
This process helps lubricate the woven fibers, provides high-temperature durability, and various fabrics.
Cage Construction for Your Filter Bag
Industrial dust collector filter bags require internal support structures referred to as cages. Cages will provide the support needed for filter bags to stay open during the dust collection cycle. The construction of your cage will depend on the design of your baghouse; top or bottom load.
Optimize Dust Collector Performance with a Maintenance Plan
There is no disadvantage to being proactive and implementing a maintenance plan for your dust collection system. It helps detect any issues before they become a larger problem. Some of the benefits of a dust collection maintenance plan are long filter life, prevention of dust collection explosions, and reduced unplanned downtime throughout the year.
If you would like additional help finding the right solution for your application, we can do that! You can contact one of our experienced account managers at 888-221-0312 or email [email protected] Already have information and just need a quote? You can also submit your specs here and get a quote in 24 hours!