Archive | Reliability & Maintenance Center

84

3:16 pm
March 13, 2017
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‘Lean’ Your Way To Workplace Efficiency

03175srandmThe 5S process has proven to be a highly effective organizational tool for modern, Lean work environments. Are your operation’s plant-floor personnel taking full advantage of this methodology?

According to experts in storage, organization, and material-handling solutions at Akron, OH-based Akro-Mils (akro-mils.com), organizations that invest in a 5S process increase productivity, create higher-quality products, and lower operating costs through simple waste removal, visual identification, and efficient use of space. By incorporating a 5S Lean methodology, they note, facilities can:

• improve workflow and productivity
• develop a cleaner, more efficient environment
• create extra workspace
• increase safety
• reduce wasted time and effort
• boost worker morale
• ensure improvements remain intact.

A recent Akro-Mils blog post provided the following refresher on steps in the 5S process, along with some ways this Lean approach can lead to improved workplace efficiency.

— Jane Alexander, Managing Editor

randm1. Sort.

The first step in the 5S Lean methodology is eliminating items that are not needed for the current workflow. This step is crucial to reducing clutter, eliminating outdated or expired materials and supplies, and freeing up valuable real estate in your workspace. A key decision point in this step is determining which items stay and which items go. Unnecessary items are moved out of the workspace and either immediately disposed of or stored offsite and dealt with later.

2. Set in Order.

Frequently used workstation materials and tools should be arranged so that all needed items are readily accessible and easy to find. In this step, the workspace is reorganized and redefined for the most efficient use of space. All tools and supplies are labeled and organized, and a system is implemented to make sure they are always returned to their proper locations.

3. Shine.

When first implementing a 5S Lean process, all work areas receive a thorough cleaning and inspection. A formal cleaning and maintenance schedule is then developed to prevent dirt from accumulating and keep equipment in proper working condition.

4. Standardize.

Benchmarking and evaluation tactics should be used in your 5S Lean process to maintain a consistent approach for carrying out tasks and procedures. For example, standardizing the storage of supplies through color-coding is an effective way to provide helpful, easily recognizable visual indicators throughout an entire facility.

5. Sustain.

The last step is to continue maintaining efficient workflow and productivity with your 5S Lean system. The best way to do that is through education and empowerment of those using the system. Communicating the benefits of an ongoing 5S process will help ensure personnel’s continued adherence to it and, just as important, that there is no falling back into bad habits. Equipping workers with a well-designed 5S checklist does more than merely support the following of those procedures. It’s an effective way to create accountability and keep this valuable process going strong. MT

For more information on 5S and other workplace topics, and to download a copy of the Akro-Mils 5S Procedure Checklist, visit akro-mils.com.

97

3:09 pm
March 13, 2017
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SAP Tips and Tricks: Maintenance Plans — What do all the fields mean?

By Kristina Gordon, DuPont

SAP Maintenance Plans determine how and when a work order or notification will be generated. (Object or notifications will be referred to as objects in this article.) The scheduling parameter settings within the maintenance plan you create dictate these rules. In response to several questions I’ve received about what should be entered and what the value represents, the following screen shot and definitions describe, in detail, the scheduling parameter settings that should be used in a typical maintenance plan. MT

1703rmcsap01p

SF (shift factor) later confirmation:

Based on the percentage entered, this will dictate the next plan date, or due date, of the maintenance plan if an object confirmation has been completed after the original due date.

Example: If the due date for a plan, generated on an object, is Jan. 1, and the maintenance plan is on a 30-day scheduling frequency, however the work and confirmation of that work is not completed until Jan. 15, a 100% late SF will generate the next object on Feb. 15, 30 days after the confirmation. If the SF later confirmation is set at 0%, then the next work order will generate on the scheduling frequency of 30 days without a shift factor calculated in, meaning the work order will generate on Feb. 1.

SF earlier confirmation:

The same rules apply as above, only this formula will calculate based on early confirmation of a work order. If set at 100% and the work is performed 15 days early, the next object will be generated 15 days earlier than the original plan date. If set at 0%, the original plan date will stay the same.

randmTolerance (+):

This determines the difference between the actual completion date and the planned date.

Example: If you set a 20% tolerance on a plan that has a scheduling frequency of 30 days, the calculation the system will use is 30 days x 20% = 6 days. That means you have a 6-day “float” period that is accepted by the system and will not affect scheduling. If you complete the job and confirm the work 6 days early, the plan will not change, i.e., the dates are in the acceptable range.

Tolerance (-):

As in the above example, the parentage calculation applies and will allow a 6-day float after the plan date.

Cycle modification factor:

This calculation is used when implementing maintenance strategies. If you have a cycle duration of 60 days, but want a plan to generate in 90 days, set the cycle modification to 1.5. This will allow the plan to generate an object in 90 days while the other plans on the same strategy will generate in 60 days. The calculation used for this example is 60 days x 1.5 = 90 days.

Factory calendar:

The factory calendar dictates when the system will process scheduling. Factory calendars can be set in the header data of the maintenance plan or at the planning plant item level.

Example: If the factory calendar is set at a 5-day workweek calendar with holidays, object will not accept confirmations on non-working days (this would include weekends and holidays). You will receive a system error message “not a working day.” To avoid this, a factory calendar should be created for maintenance that allows a 7-day, 24-hour working schedule.

Call horizon:

The calculation used in this field will determine how far in advance an object is generated before the plan due date.

Example: On a 30-day plan, if the call horizon is set at 25%, the work order will generate 21 days before the plan due date of the object. It is very important to set your call horizon so that an object is generated so that the job can be planned well in advance of the plan due date.

Scheduling period:

The scheduling period indicates, in days, months, or years, how far in advance you want to see your maintenance calls.

Example: If you set the scheduling period for 365 days, the system will show the calls for that plan for one year in advance. This will help with long-term planning.

Requires confirm:

When you check this powerful box, the system determines when the next object will be generated from the plan. It will only generate when the previous call object has been completed. If you do not check this box, the system will not take into consideration whether the previous object was completed and will generate the next work order on the call date assigned.

Scheduling indicator:

This indicates when to schedule your plan. It will use time, which works in conjunction with the tolerance percentages. Time key date, which will always use the actual date, and factory calendar take into consideration the working days set in the calendar entered.

Kristina Gordon is SAP PM Leader, DuPont Protective Solutions Business, and SAP WMP Champion, Spruance Site, Richmond, VA. If you have SAP questions, send them to editors@maintenancetechnology.com and we’ll forward them to Kristina.

357

2:58 pm
March 13, 2017
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Keep Stored Gear Reducers Service Ready

When gear reducers and other capital spares are improperly prepared for storage, their service readiness can be seriously compromised.

When gear reducers and other capital spares are improperly prepared for storage, their service readiness can be seriously compromised.

Are your statically stored gear reducers service ready? That’s the first of several questions from Dillon Gully of Motion Industries (headquartered in Birmingham, AL, motionindustries.com). He has good reason for asking. In conducting borescope inspections of statically stored internal-gear reducers for customers, Motion Industries personnel discovered as many as one-third of these assets sitting on shelves in a failed state.

Next questions: Are you willing to gamble the OEE (overall equipment effectiveness) and profitability of your facility on gear reducers and, for that matter, other capital spares that might not be service ready? What would you tell your boss if a critical spare were to fail within mere hours? Think this scenario doesn’t apply to you? How can you be sure? Gully offers some advice for achieving peace of mind.

— Jane Alexander, Managing Editor

Effective management of capital spares involves up-front identification of these assets and making sure they are in service-ready condition prior to preparing them for long-term storage. Unfortunately, many operations don’t follow through on this process once purchased units arrive on site. According to Gully, these steps are the only way to support the reliability of stored spares.

Capital spares can be defined as any item that is critical to production, promotes safety, decreases downtime, and/or prevents environmental issues. Gear reducers certainly qualify. The best way of verifying that these assets won’t fail as soon as they’re put into service is to inspect them before they are stored away—perhaps for years. Minimally invasive borescope inspections are a particularly good inspection method.

In a borescope inspection of a gear reducer, a camera scope visually inspects the condition of bearings, gearing, and internal components. The procedure can be accomplished through a plughole, which prevents contamination of an asset, if it is, indeed, ready for service. (Compared to the cost of replacing a failed bearing, costs associated with borescope inspections are also minimal.)

randmStorage planning

While information gleaned from borescope inspections can be used to confirm service readiness—or help identify steps for making a spare service ready—it can also help determine how to prevent these units from improper storage.

Corrosion, i.e., rust and contamination, are two, of many, causes of failure in gear reducers. When borescope inspections identify the presence of these failure modes, steps can be taken to correct them before the equipment is put into storage, as well as prevent those problems from recurring during storage.

Once a plan to prevent failures in stored spares is developed and implemented, it should be consistently followed. Every unit that will be stored, for whatever period of time, should be carefully protected. Preventing rust and contamination is a great start in protecting asset reliability and, thus, ensuring service readiness.

An ongoing process

Keeping stored spares in service-ready condition requires management accountability. Someone must be assigned responsibility for these assets, and expectations should be clear and realistic. It’s the responsibility of that designated person to ensure all spares are properly prepared and maintained. Identifying failed spares and bringing them back to service-ready condition is an ongoing process. As Dillon Gully emphasizes, “It should not be done one time and then forgotten.”

This plan for reliability can lower the probability of failure and bring a welcome degree of certainty regarding your stored gear reducers and other capital spares. MT

Working as an analyst for Motion Industries’ service center in Pensacola, FL, Dillon Gully has been conducting vibration and borescope inspections and managing capital spares for three years. For more information on these topics, visit motionindustries.com or bearings.com.

57

2:53 pm
March 13, 2017
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Mine Business Intelligence From Your CMMS

Car BoomBusiness Intelligence (BI) analysis is crucial to an operation’s success. In short, this analysis is the harnessing of software to mine an organization’s raw data. Analyzing that data through the use of reporting and analytics can support critical business decisions.

In the maintenance world, a computerized maintenance management software (CMMS) system plays a vital role in collecting useful data. Technical experts at Mapcon Technologies Inc. (Johnston, IA, mapcon.com) point to five areas where these systems can help your organization analyze and understand its valuable business intelligence and put it to use.

— Jane Alexander, Managing Editor

Inventory auditing

It’s important for maintenance personnel to know how many parts are needed and when they need to be reordered. By running an inventory usage report within a CMMS, users can find out exactly how many individual parts were used over a specific period of time. Once that information is gathered, a minimum number, or reorder point, of parts can be established to trigger an automatic reorder that, in turn, would be approved and sent to the vendor. This can ensure that stock-outs are no longer a problem and, accordingly, prevent downtime.

randmPredictive analysis

For maintenance departments, being able to predict when equipment will fail is a big deal. A CMMS can determine, based on meter or gauge readings and historical data, when a machine is most likely to break down. Take, for example, a machine that breaks a belt approximately every 1,000 hr. Since a CMMS would display that trend, a technician could set up a preventive–maintenance (PM) task to change the belt every 950 hr. By using a CMMS to predict when the machine will break a belt, downtime can be avoided.

Preventive-maintenance compliance

Since PM information is stored within a CMMS, it is easy to analyze. When reviewing such data, managers can break it down by type of work done, employee, area, or other metrics, and make necessary changes. For example, by determining why certain PMs weren’t completed on time, they could take steps to hire new workers or provide additional training to current employees.

Failure analysis

A CMMS stores an extensive amount of historical data, including repairs, for each piece of equipment in a plant. Therefore, when personnel notice that machines have required numerous repairs, they can analyze stored failure codes to help determine root causes. They can also review CMMS information on when repairs were done, associated downtime, and PM activities, among other things, to devise corrective measures. Say a technician discovers that a machine breaks more belts in the winter due to colder temperatures. With this information, he or she could plan ahead and turn up the heat in the area or order more belts to have on hand during winter months.

HR (human resource) reporting

Reports within a CMMS can be run for things other than maintenance-repair information. Many software programs can run HR-related reports, i.e., an open work order by craft or shift report. This capability allows managers to view the workload according to shift or craft, something that can be beneficial when it comes to hiring decisions. MT

For more information from Mapcon Technologies on this and other CMMS topics, visit mapcon.com.

74

2:46 pm
March 13, 2017
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Eliminate Electrical Arc-Related Dangers

1703rmcelectric_AdobeStock_58371295.jpegLike any energy source, an electrical circuit is a ticking bomb, just waiting for the right conditions to blow. As Finley Ledbetter, CEO of Group CBS (Addison, TX, groupcbs.com), explains, “A twisted pole, faulty interlock, and enough energy will turn an electrical firecracker into mortal lightning strike.”

Protecting personnel from arc-flash and arc-blast dangers isn’t an option — it’s mandatory according to OSHA and NEC requirements. According to Ledbetter, compliance starts with an accurate arc-flash calculation based on real field tests that can pay double dividends when the findings are used in a preventive-maintenance (PM) program. “But realize,” he cautions, “any time electrical equipment with sufficient fault current is operated, there is a danger. And PPE will not always protect workers.”

Ledbetter offered several tips for managing arc-flash risks.

—Jane Alexander, Managing Editor

Avoid common mistakes.

randmTechnicians refer to the National Electrical Code (NEC), Tables 130.7(C)(9-11), which define hazard risk categories (HRCs) for various classes of equipment, as well as what level of PPE employers need to provide to employees based on the minimum arc thermal performance value (ATPV). A common mistake is to determine the HRC and required PPE level based solely on the class of equipment instead of the actual 70E standard requirements. This approach assumes that the fuse or circuit breaker will actually perform to the OEM specification. A failed OCPD or even a slow breaker will result in higher incident energies than your technician’s PPE protection when the arc-flash calculation is based solely on OEM specifications.

Develop a maintenance-planning schedule.

Good maintenance is a first line of protection against arc flash/blasts. NFPA’s 70E Article 205.3 requires that all electrical equipment be maintained in association with the OEM instructions or industry standards. NETA’s maintenance frequency MTS table, based on equipment class and an environmental condition, is a good place to start when developing your PM-planning schedule. The best way to determine the arc-flash danger for a given device in a given installation is to use IEEE’s standard 1584 arc-flash calculations based on actual test data for the given device at a given installation.

Know that not all switchgear is arc-flash resistant.

Older switchgear and panel boards were not made with built-in remote actuators and extraction/racking capabilities, even though myth has it that switchgear is designed with arc-flash containment in mind. OEMs have started to develop switchgear cubicles with integrated remote actuation and racking/extraction features, and you can easily search the Internet for the latest equipment design. For a premium, this switchgear allows your technicians to actuate the OCPD or other device while it is still behind the metal enclosure. Arc-flash-resistant switchgear also strives to direct the arc flash up and away from the technician. Arc-flash-resistant switchgear that complies with IEEE C37.20.7 with remote actuation and racking/extraction is a move in the right direction, but it can be prohibitively expensive to replace all your aging switchgear with new enclosures and gear.

Use remote actuation and racking systems to keep your distance.

A number of portable remote actuation/extraction/racking systems work on virtually any OCPD or motor-control center and enclosure. Rather than having an embedded unit for each cubicle, these systems come with a portable design and power supply. In some cases, the technician can stand as far as 500 ft. away from the gear in question, well outside the arc-flash and arc-blast danger boundaries. These portable systems can also provide PM data on the force required to rack a unit. The best examples of remote racking/actuation work with horizontal or vertical racking systems, use magnetic latching that does not require any modification to existing equipment, and accommodate a variety of equipment makes and models. MT

Through a number of affiliated companies in the U.S. and U.K., Group CBS Inc., Addison, TX, provides electrical solutions and services for customers in the industrial, utility, power-distribution, and repair markets around the world. For more information, visit groupcbs.com.

273

6:58 pm
February 10, 2017
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Obsolete Inventory? Deal with It.

randmObsolete. Everyone who has ever purchased a computer knows what that means. It describes your computer within a month or so of your purchase.

When the discussion turns to a plant’s MRO inventory, Roger Corley of Life Cycle Engineering (LCE.com) says it’s an entirely different type of conversation. That’s because some items are never used, yet continue to collect dust and take up valuable storeroom real estate. He has some tips for dealing with this obsolescence, starting with how to identify it.

Identifying obsolete MRO inventory, in Corley’s opinion, is the easy part, especially if a good set of parameters has been established. Most large storerooms, he says, apply these factors:

• items with movement (receipts or issues) in 3+years

• items that aren’t identified as critical spares

• items that aren’t on an active asset’s BOM (optional).

Up-front planning can ease your site’s identification and disposal of obsolete MRO items.

Up-front planning can ease your site’s identification and disposal of obsolete MRO items.

With these parameters in place, most inventory systems can quickly generate a list of obsolete items—something that should be done annually to make it easier to manage the following years’ lists.

According to Corley, the more difficult (politically charged) challenge associated with obsolete MRO items is their disposal. That’s why storeroom managers must be involved in a site’s budget-preparation process. For one thing, there will need to be a line item in the budget for disposal of inventory. In addition, since writing off unused inventory can be damaging to a company’s bottom line, it’s crucial to prepare (and obtain approval) for doing so ahead of time.

Another issue involves disposing of what personnel believe “belongs” to them. As Corley put it, “I’ve seen maintenance supervisors and managers dig in their heels when a storeroom manager begins removing what they think of as ‘their’ MRO items.” His advice to storeroom managers is to take great care to ensure important items that might have been left off the list of critical spares aren’t eliminated from inventory. Some front-end work on the part of storeroom managers can smooth the process. Such work includes:

• investigating the history of the proposed item considered for disposal

• grouping items into specific operating areas on site and scheduling meetings to review (tip: buy lunch to get participation)

• allowing area managers to present a case for inclusion of a critical spare and being prepared to offer solutions such as vendor-stored inventory.

Once a list is developed and agreement among stakeholders reached, the obsolete items must be removed from inventory and disposed of. Corley notes that this phase will be less painful in plants that have investment-recovery departments. Smaller operations will sometimes list the obsolete inventory on bidding sites or, in the case of metals, recover money by scrapping items.

“Either way,” he cautioned, “sites shouldn’t expect to get anywhere near what the initial investment was when the items were purchased. In the case of scrap, they’ll recover pennies on the dollar. As for companies with multiple plants, it’s important for sites to check with other locations regarding possible use of obsolete items before disposing of them.”

To Corley’s way of thinking, dealing with obsolete MRO inventory, including identifying and disposing of it, needn’t be viewed as a daunting task. “That is,” he said, “if the process is managed properly and homework is done before the items are removed.”  MT

—Jane Alexander, Managing Editor

Roger Corley is a Materials Management subject-matter expert with Life Cycle Engineering, Charleston, SC, and a certified facilitator for Maintenance Planning and Scheduling with the Life Cycle Institute. For more information, email rcorley@LCE.com and/or visit LCE.com.

239

6:39 pm
February 10, 2017
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Infrared Inspections Of Installed Motors

By Jim Seffrin, Infraspection Institute

randmDespite the important role they play in facilities, electric motors often tend to be out of sight and out of mind—until they fail. Infrared thermography can be a cost-effective diagnostic tool for detecting problems within these systems.

Many infrared (IR) inspection programs focus on motor control circuits, but overlook the actual motors. Infrared inspections of a motor’s bearings and stator should be performed monthly by an experienced, certified IR thermographer that thoroughly understands the theory and operation of electric motors.

Here are the basic steps for performing this type of inspection:

1. Inspect motor casing for localized hotspots that may be indicative of short circuits within motor windings.

2. Qualitatively compare individual motors to similar motors under similar load.

3. When possible, qualitatively compare inboard and outboard bearings for each motor. If a large Delta T is present, it may be indicative of misalignment or a rotor balance problem. If both bearings are hot, the bearings may be worn or improperly lubricated.

4. Additionally, a thermographic inspection of the electrical connections within the motor junction box should be performed annually. This may be done in conjunction with a regularly scheduled IR inspection of the facility’s electrical system.

Because no complicated analysis is required, infrared inspections typically can be performed rapidly and at a fraction of the cost of other types of motor testing. Infrared can also detect evidence of misalignment at lower thresholds than those detectable by vibration analysis and motor-current signature analysis. MT

Words to the Wise: Stick to Facts

0217rmcinfraWhen used as a preventive/predictive maintenance tool, infrared (IR) thermography can detect and document evidence of thermal patterns and temperatures across the surface of an object. The presence of inexplicable thermal anomalies or exceptions is often indicative of incipient failures within inspected systems and structures. Because thermography alone can’t determine the cause of an exception, other diagnostic tools must be employed.

Some thermographers, however, provide opinions as to the cause of exceptions without the benefit of confirming test information. Such opinions are frequently accompanied by elaborate recommendations for repair. When those observations/recommendations are incorrect, they can cause repair efforts to be misdirected.

Unless a thermographer has performed, or has access to, confirming tests, it’s unwise to provide opinions regarding the cause of exceptions and offer suggestions for repair. Lacking confirming test data, a prudent thermographer should make only one recommendation: “Investigate and take appropriate action.”

This simple recommendation can be applied to any thermographic inspection and serves to avoid unnecessary liability by eliminating guesses and sticking to facts.

— J.S.

Jim Seffrin, a practicing thermographer with 30+ years of experience in the field, was appointed to the position of Director of Infraspection Institute, Burlington, NJ, in 2000. This article is based on one of his “Tip of the Week” posts on IRINFO.org. For more information on infrared applications, as well details on upcoming training and certification opportunities, email jim@infraspection.com or visit infraspection.com.

94

9:28 pm
February 9, 2017
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Ensure Clean, Dry Compressed Air

randmWhen it comes to compressed-air systems, equipment performance is only as good as the quality of the air itself. Unfortunately, the high-pressure air that these systems produce is wet and dirty. Air dryers and filters keep a compressed-air system operating efficiently, but only if they are properly maintained.

All atmospheric air contains some moisture and dirt. No matter how small the amount of contaminants initially, they are concentrated when the air is compressed. As the air heats up, its ability to hold water vapor increases. When the air begins to cool as it travels downstream, the vapor condenses into liquid.

Possible consequences of that condensation include, among other things, leaking seals, rusty or scaling pipelines, premature wear of moving components, and similar problems that can lead to subpar operation, equipment failure, and even damaged finished product. Plant personnel can prevent many of these headaches by selecting the right types of air dryers and filters to remove the liquid and particles and by performing regular maintenance on these
components.

Compressed-air experts at Mazeppa, MN-based La-Man Corp. (laman.com) offer several tips regarding air dryers and filters. Keep them in mind.

—Jane Alexander, Managing Editor

Types of dryers

Most compressors incorporate an aftercooler to reduce the temperature of the compressed air. Air dryers are often installed to further reduce the moisture content. There are four major types of air dryers:

• refrigerated

• chemical or deliquescent

• regenerative or desiccant

• membrane or mechanical.

Condensation in compressed-air systems can lead to a multitude of ills, including equipment failure and damaged finished product.

Condensation in compressed-air systems can lead to a multitude of ills, including equipment failure and damaged finished product.

The simplest, most economical dryer is the membrane or mechanical type. It uses a textile filter made up of thousands of individual fibers to trap large particles and cause moisture to form large droplets (coalesce). These particles and droplets collect at the filter’s base and are drained off. Water vapor passes through the filter to a sweep chamber, where it is vented.

Mechanical systems are typically installed at the point of use (unlike desiccant-type dryers that are placed near the air compressor to capture water vapor). At this point, air temperature has cooled sufficiently to permit water droplets to form and be captured by the system.

Impact of air filters

Mechanical filters work with compressed-air dryers to remove water and other contaminants from the compressed air and prevent component contamination. Three types of filters are typically used:

• particulate

• coalescing

• adsorption.

Particulate filters are typically made of a fine mesh glass fiber, plastic fiber, or woven wire cloth. They remove large particles using centrifugal force, while smaller particles are strained out. The filter is rated by the largest-size particle it will allow to pass. These types of filters work hand in hand with coalescing filters.

Coalescing filters are high-efficiency filters that use a fine stainless-steel mesh or woven fiber cloth (such as a cotton co-knit) to remove water and lubricants from the compressed air. They are often installed downstream of a particulate filter.

Adsorption filters use activated carbon to remove gaseous contaminants from compressed air. They adsorb the oil vapor into the pores of the carbon granules and must be replaced once saturated with collected oil. They are point-of-use filters, which should be supported upstream by a coalescing filter. Typical uses for adsorption filters include sanitary environments, such as paint spray booths, clean rooms, and food and beverage manufacturing.

Bottom line: Using—and maintaining—filters dramatically improves the performance and extends the life of compressed air systems. MT

For more information on solutions that remove water, oil, and contaminates from compressed air systems, visit La-Man Corp. at laman.com.

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