Hy-Pro Filtration Case Studies

Automotive

Automotive Manufacturing Stamping - FCL10 off-line filter cart and DFE Rated G8 Dualglass Filter Element Upgrades

A major automotive stamping plant was struggling with costly surface finish defects traced back to contaminated lubricating oil in its uncoiler/washer system. Despite having an off-line filtration system in place, oil analysis revealed high ISO cleanliness levels—and, more critically, cellulose fibers shedding directly from the existing depth-type filter inserts. These contaminants were transferring to stamped panels, resulting in visible paint defects and significant scrap costs.

This case study details how the facility partnered with Donaldson Hy-Pro to perform a complete system clean-out, dramatically lower ISO codes, and eliminate fiber shedding altogether. By purifying the oil with high-efficiency 6M media, replacing cellulose inserts with HP2727L43-6MB pleated glass elements, and restoring the cleaned fluid to the system, the plant achieved a stable ISO code of 17/13/9 within 17 days—and produced zero defective parts. The transition not only eliminated finish defects but also extended filter life, preserved oil quality, and delivered substantial annual savings. The results were further validated when reintroducing the original filters caused ISO levels to spike again, confirming the root cause and the effectiveness of the solution.
Diesel Fuel Filtration Upgrades - DFE Filter Element Upgrades - FL and COD

Modern diesel engines are more powerful, efficient, and cleaner than ever—yet many operators still face premature wear, rising maintenance costs, and unexpected downtime. The culprit is often overlooked: fuel that falls far short of the cleanliness levels today’s high-pressure fuel injectors require. This case study explores how one operation tackled fuel contamination head-on by implementing a targeted ISO cleanliness goal of 16/14/12 and deploying a strategic, three-stage filtration approach across storage tanks, dispensers, and equipment.

By filtering fuel to 1 micron before it ever reaches the engine—and retaining OEM filters as a final safeguard—the organization significantly extended injector life, reduced fuel dilution and filter replacements, and improved overall engine performance and efficiency. The results include measurable cost savings, lower emissions, and reduced waste-handling charges. This case study demonstrates how proactive fuel filtration not only protects advanced diesel systems but also unlocks the full potential of today’s engine technology.
FPL Saves Servo Valves - FPL Filter Panel & Spin-On Breather

A leading tire manufacturer was facing excessive downtime and steep maintenance costs as inadequate filtration across 35 tire grinders led to chronic servo valve failures. With nearly 200 valve repairs or replacements in a single year—at an average cost of $2,200 each—the plant needed a proven, long-term solution. Oil analysis revealed the root of the issue: contamination levels far above the ISO cleanliness requirements for sensitive servo valves.

This case study outlines how the manufacturer partnered with Donaldson Hy-Pro to implement a total system cleanliness strategy, beginning with the installation of a custom-engineered FPL off-line filtration panel and a high-efficiency breather to stop particulate ingression. Within days, the system’s ISO code dropped from 22/20/17 to an impressive 13/9/7, representing a 99.8% reduction in harmful particles. With similar upgrades rolled out to all 35 grinders, servo valve failures plummeted—from 198 per year to a projected six—while production efficiency increased by 2% thanks to consistently stable valve performance. This case demonstrates how targeted off-line filtration can dramatically cut maintenance costs, prevent unplanned downtime, and deliver measurable productivity gains.

Construction

Caterpillar Service Center 5-Star Solution - ISO Codes

Achieving and maintaining Caterpillar’s prestigious Five Star contamination control rating requires absolute confidence in fluid cleanliness—from bulk storage tanks all the way to the machine. This case study highlights how Michigan CAT transformed its service center’s contamination control program with a comprehensive, multilayered fluid filtration strategy designed to meet strict CAT cleanliness specifications for hydraulic, transmission, and engine oils.

By installing dedicated in-shop and mobile filtration systems, mounting high-efficiency filters in series, and ensuring each fluid type received the correct combination of filtration passes, Michigan CAT was able to consistently deliver oil that met or exceeded target ISO codes. The solution included wall-mounted filtration for service bay dispensing, high-flow filter assemblies for bulk-to-truck transfers, on-board truck filters for field service, and Hy-Dry desiccant breathers to block moisture and airborne particulate. Patch testing, particle counting, and documented oil analysis verified ongoing compliance and provided clear traceability.

Through systematic filtration, last-chance strainers, and disciplined cleanliness monitoring, the service center successfully maintained the cleanliness levels required for CAT’s Five Star rating—ensuring customers receive cleaner fluids, better equipment protection, and higher service quality across every operation.
Hitachi Excavator Hydraulic System - Filter Element Upgrade

Mining environments are notoriously harsh on hydraulic systems, and the Hitachi EX2500 excavator in this case was no exception. Operating in a high-ingression environment, the machine suffered repeated premature component failures—including multiple piston pumps, swing motors, drive motors, servo valves, hydraulic hoses, and contamination sensors. Over its first 27 months, these failures led to more than 39 hours of unplanned downtime and substantial repair costs, severely impacting productivity.

This case study examines how implementing a robust contamination control strategy transformed hydraulic system reliability in one of the toughest operating conditions. By targeting the root cause—particle contamination—the mine significantly reduced component wear, stabilized system performance, and drastically cut unscheduled downtime. The results highlight the critical importance of maintaining clean hydraulic fluid to protect high-value components, reduce maintenance expense, and ensure consistent, dependable excavation performance in the field.
Hydraulic Valve OEM System Upgrade Reduces Failures - DFE Rated Filter Elements

A major manufacturer of mobile hydraulic valves for heavy-lift equipment was facing recurring production disruptions caused by contamination-related failures across four assembly lines. To pinpoint the cause and validate a solution, the company conducted a four-month, head-to-head trial: one line was upgraded with Donaldson Hy-Pro filter elements, while another continued operating with the originally specified filters. With a target ISO cleanliness code of 17/15/13, the test provided a clear comparison of real-time fluid performance.

The Donaldson Hy-Pro elements—engineered for high-efficiency particle removal—produced dramatic improvements in fluid cleanliness, delivering a 99.9% reduction in particles at 4µ[c], 6µ[c], and 14µ[c] and far surpassing the performance of the original filters. When paired with enhanced maintenance practices, the upgraded filtration system consistently exceeded target ISO codes and stabilized product quality.

As a result, all four production lines were converted to Donaldson Hy-Pro elements, leading to significant reductions in downtime, higher productivity, and the near elimination of hydraulic leaks and equipment-related failures. This case demonstrates how improved filtration can directly enhance manufacturing reliability, efficiency, and end-product quality.

Energy

Coal Pulverizer Gearbox Filtration Upgrade - FSL Offline FIltration

Coal-fired power plants rely on large coal pulverizer gearboxes that operate under heavy loads and harsh conditions—yet many run without dedicated filtration, leaving high-viscosity lubricants heavily contaminated long before scheduled oil changes. In this case study, routine analysis revealed that gearbox oil was far dirtier than acceptable for any lubrication system, contributing to accelerated wear, costly maintenance, and reduced equipment life.

By implementing a comprehensive total system cleanliness approach—including continuous off-line filtration, targeted ISO cleanliness goals, high-efficiency breathers, and condition-based oil change practices—the plant transformed gearbox reliability. After installing an FSL side-loop filtration system and charging the gearboxes with fresh synthetic oil, contamination levels dropped dramatically in less than 24 hours. Particle counts fell by thousands per milliliter, ultimately achieving servo-quality cleanliness and continuing to improve over the following months.
FSAPE Optimizes Peaking Power Plant -TMRN2 reservoir headspace dehydrator

Peaking power plants operate under strict time constraints—when the grid calls, they must start quickly and reliably. For one combined-cycle plant, repeated unit trips and fail-to-starts were being driven by electrohydraulic control (EHC) servo valve failures. Contamination in the phosphate ester fluid—including water, acids, particulate, gels, dissolved metals, and low resistivity—was threatening system reliability, forcing costly outages, and prompting the maintenance team to consider a complete fluid replacement.

This case study describes how implementing a comprehensive Total System Cleanliness strategy reversed the trend. By installing an FSAPE2 off-line acid remediation and particulate filtration skid, adding a TMRN2 headspace dehydrator, upgrading the discharge filter to high-efficiency microglass, and protecting the reservoir with a desiccant breather, the plant addressed every major contamination source at once.

Within four months, fluid quality returned to specification, resistivity stabilized, and gel formation was eliminated—removing the root cause of the servo valve issues. As a result, the plant stopped experiencing trips and fail-to-starts and avoided the expense of replacing its phosphate ester fluid. This transformation demonstrates how targeted contamination control can drastically extend fluid life, restore reliability, and protect profitability in high-risk peaking power applications.
SVR Saves Coal-Fired Power Plant

During a scheduled shutdown at a coal-fired power plant in the Philippines, turbine lube oil—Shell Turbo 32—was found to have rapidly degraded, with MPC values soaring to 250 and ISO cleanliness at 20/17/10. The oil was deemed unusable, and the plant urgently attempted to source 60,000 liters of replacement fluid. When the supplier could not deliver within the shutdown window, the plant faced the risk of extended downtime, missed restart deadlines, and severe operational and financial consequences.

This case study details how the plant avoided unnecessary costs and outages by deploying a rapid-response contamination control strategy. Working with a Donaldson Hy-Pro distributor and representative, the team installed two SVR1200 Soluble Varnish Removal units equipped with ICB technology, supported by continuous sampling and ready-to-swap filter sets to ensure uninterrupted cleanup.

Within the scheduled shutdown period, the SVR systems reduced MPC and ISO values enough to safely restart the turbine—and continued restoring the fluid over the following months. After six months of continuous filtration, the oil reached better-than-new condition, with MPC reduced from 250 to 6.54 and ISO codes improved from 20/17/10 to 13/12/11. Instead of spending $200,000 on new oil, the plant resolved the issue for under $40,000, saving more than $160,000 while achieving superior fluid cleanliness.
Wind Turbine DFE Filter Element Upgrade

Wind turbine gearboxes operate under demanding conditions, relying on clean, reliable lubrication to protect complex, high-value gearing systems that are difficult and costly to access. In this wind farm, elevated fluid contamination levels were putting gearbox components at risk and increasing the potential for unplanned downtime—an outcome that not only drives up maintenance costs but also undermines energy reliability metrics critical for community and government confidence. With long service intervals and challenging accessibility, maintaining optimal oil cleanliness is essential to preserving gearbox life and keeping turbines producing power consistently.

To resolve the issue, the operator upgraded to high-efficiency Donaldson Hy-Pro filter elements and improved breather technology designed to capture airborne particulate more effectively. After upgrading 55 turbines, the wind farm achieved substantially cleaner gearbox oil and extended component life, reducing maintenance risk and improving operational efficiency. With critical components located hundreds of feet in the air, the enhanced cleanliness control provided both measurable reliability benefits and valuable peace of mind for maintenance teams, ensuring that fewer interventions—and safer, more productive turbine performance—could be maintained over the long term.

Manufacturing

Aluminum Refinery Gearbox Oil - DFE G8 Dualglass Filter Elements and Vacuum Dehydration

An Australian aluminum refinery was facing excessive downtime and soaring maintenance costs due to premature gearbox oil changes driven by severe particulate and moisture contamination. With ISO cleanliness levels averaging 20/18/16 and water content nearing 4,742 ppm, each of the refinery’s seven base drive units required frequent replacement of 360 liters (90 gallons) of ISO VG320 gear oil—costing nearly $18,000 per change and more than $125,000 across all units. These conditions threatened equipment reliability, increased environmental waste, and placed unnecessary strain on maintenance teams.

By deploying a Donaldson Hy-Pro V5 vacuum dehydrator on a rotating schedule, the refinery rapidly restored lubricant health across all gearboxes. The system removed free, dissolved, and emulsified water while capturing fine particulate using high-efficiency filtration, turning each sump volume more than 75 times per day. The results were dramatic: a 98% reduction in water contamination, a 95% drop in particulate levels, and a significant improvement in ISO cleanliness codes. With cleaner, longer-lasting oil and improved gearbox life—projected to extend by 2.5×—the refinery achieved measurable reliability gains, substantial cost savings, and a meaningful reduction in its environmental footprint.
Hydraulic Pump Reliability - Improved with a Dualglass Filter Element Upgrade

A hydraulic valve manufacturer was experiencing frequent and costly pump failures within its centralized hydraulic system, losing approximately 25 pumps per year. While each pump replacement cost $2,440, the true impact was far greater—totaling more than $25,000 per failure once maintenance labor, lost oil, and production downtime were included. Fluid analysis revealed severe contamination, with ISO cleanliness levels as high as 22/21/19, directly contributing to premature pump failure and reduced system reliability.

Working with Donaldson Hy-Pro, the manufacturer implemented a comprehensive contamination control strategy to restore fluid cleanliness and protect critical components. Environmental ingression was eliminated by sealing hydraulic tanks and installing high-efficiency breathers, while offline filtration performance was significantly improved by upgrading to a finer, more efficient filter element. Over a 140-day monitoring period, fluid cleanliness improved dramatically to an ISO code of 12/11/7—far exceeding the target of 17/15/13. The result was a substantial reduction in contamination-related failures, improved system reliability, and increased productivity across operations.
Valve Performance - Testing and Clean Oil - Improvement Through Fluid Handling and Sampling Practices

A hydraulic valve manufacturer required exceptionally clean oil to accurately validate valve performance on a test stand measuring flow across an 80-micron orifice. With a target ISO cleanliness level below 14/12/9, even small amounts of particulate contamination could compromise test accuracy and invalidate results. However, the 100-liter (26.4-gallon) ISO VG32 fluid in the test stand reservoir was operating at an ISO code of 19/18/16—far exceeding acceptable contamination levels and placing critical testing at risk.

To resolve the issue, the onboard filtration was upgraded to a high-efficiency 1-micron filter element capable of achieving the required cleanliness in a single pass. While initial bottle samples appeared to show only marginal improvement, further investigation revealed that the fluid itself had reached the desired cleanliness levels, as confirmed by an online particle monitor reading 14/11/0. The root cause was traced to improper fluid sampling practices that were contaminating the samples, not the oil. By correcting the sampling process, the manufacturer was able to validate clean oil conditions, ensure accurate valve testing, and avoid unnecessary fluid replacement—saving time, cost, and effort while preserving test integrity.

Mining

Donaldson Hy-Pro Element Upgrade Outperforms OEM in Copper Mine

A high-production copper mine operating a Nordberg® MP Series™ crusher depended on a duplex lubrication filtration system equipped with competitor-supplied elements. Over time, the mine experienced rising operating costs driven by frequent element changes, excessive oil consumption, pump wear, and suboptimal system cleanliness. These challenges not only increased maintenance expenses but also put critical equipment reliability at risk in a demanding mining environment.

Donaldson Hy-Pro, working proactively with its distributor, introduced an upgraded filtration solution engineered to outperform the existing elements. By implementing a proprietary Hy-Pro element design, the mine achieved dramatic improvements in filtration efficiency, oil cleanliness, and component protection. The results included over $490,000 in combined annual savings through reduced element costs, extended oil life, and fewer pump replacements—along with a 96.4% reduction in damaging particles. This case study highlights how Donaldson Hy-Pro delivered superior performance, lower total cost of ownership, and long-term reliability for a mission-critical mining application.

Product Reviews

COT Turbine Oil Coalesce Skid Application

A power generation facility was experiencing elevated water contamination in a turbine lubrication system, putting oil condition and equipment reliability at risk. During startup, water levels in the 800-gallon turbine lube reservoir were measured at nearly 800 ppm—high enough to accelerate oxidation, reduce lubricant life, and threaten turbine performance. To address ongoing water ingress and improve oil health without interrupting operations, the facility evaluated a dedicated coalescing solution for continuous water removal .

This case study demonstrates how installing a Donaldson Hy-Pro Turbine Oil Coalesce (COT) skid rapidly and effectively reduced water contamination. At startup, the COT system lowered water levels from 788 ppm at the inlet to just 90 ppm at the outlet, and after several hours of operation, reservoir water levels stabilized near 82 ppm. Operating continuously and unattended, the coalesce skid delivered greater than 95% water removal efficiency while also providing particulate control. The results highlight how coalescing technology can protect turbine lubricants, extend oil life, and serve as a critical component of a total turbine lube oil conditioning strategy .
SVR Extends Fluid Life

Maintaining antioxidant (AO) levels is critical to extending lubricant life and preventing varnish, sludge, and deposit formation in turbine lubrication systems. Using RULER (Remaining Useful Life Evaluation Routine) analysis, operators can quantify and trend phenol and amine antioxidant depletion—key indicators of oil health. When phenol antioxidant levels fall below 20% of new oil, oxidation rates can accelerate rapidly, often forcing premature oil condemnation and costly fluid changeouts.

This case study demonstrates how implementing SVR technology and proper filtration maintenance significantly reduced antioxidant depletion and prevented varnish formation. By stabilizing oxidation and protecting additive chemistry, the system was able to keep oil in service even when phenol levels dropped below traditional condemnation limits. The result was extended fluid life, reduced maintenance intervention, and improved long-term system reliability—showcasing the value of proactive contamination and oxidation control in critical turbine lubrication applications.
SVR Reduces MPC by 90% in 45 days

A 7FA gas turbine was experiencing repeated unit trips caused by varnish-related sticking servo valves, with oil analysis confirming a critical varnish condition. Colorimetric patch analysis showed an MPC value of 60, indicating a high concentration of soluble varnish precursors in the 6,000-gallon turbine lubrication system. Compounding the issue, phenolic antioxidants were severely depleted—at approximately 5% of new oil—placing the fluid well below traditional condemnation limits and making an oil change appear inevitable.

This case study shows how installing an SVR1200 system rapidly restored oil condition and system reliability. Within just 45 days, the MPC value dropped from 60 to 6, returning the oil to a condition-normal state despite depleted antioxidant levels. Varnish deposits were removed from filters and servo components, eliminating varnish-related fail-to-start events and unit trips. Maintenance intervals were extended from monthly component replacements back to a 12-month preventive maintenance schedule, delivering improved reliability, reduced maintenance costs, and extended oil life without a costly fluid changeout.
SVR Restores Heavily Varnished Gas Turbine

This case study highlights how an SVR1200 system successfully restored a heavily varnished gas turbine lubrication system to normal operating condition. Initial monitoring showed a rapid reduction in MPC varnish potential from critical levels, followed by continued improvement after scheduled SVR element replacement—demonstrating the importance of condition-based monitoring to maximize system recovery.

The results show that even severely varnished systems can be effectively cleaned and stabilized without an immediate oil change. By using MPC or QSA testing to guide maintenance and element changeout, the turbine achieved single-digit MPC values and transitioned from corrective cleanup to long-term maintenance mode, improving reliability and extending oil life.
V1S Saves Season for Fishing Vessel

When a seal failure allowed salt water to contaminate the hydraulic system of a 245-ft purse seiner, the vessel faced an urgent operational crisis. Water ingress rendered the net hauler unreliable and threatened costly downtime at sea or repeated hydraulic fluid changeouts—each exceeding $9,000 plus disposal costs. With fishing revenue on the line and no immediate opportunity for repairs, the vessel owner needed a solution that would restore hydraulic performance and keep operations running.

This case study details how a V1S portable vacuum dehydrator was deployed to rapidly remove water from the 265-gallon hydraulic reservoir. Over a 10-day period, water levels were reduced from more than 28,000 ppm to a safe operating range, restoring net hauler functionality well before the target threshold was reached. In total, at least seven gallons of water were removed, allowing the vessel to remain fully operational and avoid unnecessary fluid replacement. The results demonstrate how proactive water removal can prevent downtime, protect hydraulic systems, and save an entire fishing season.

Paper and Saw Mills

Papermill's Filter Element Lifespan Increased with Hy-Pro Elements and Education

A large, continuously operating paper mill was facing rising maintenance costs and reliability risks due to frequent lube filter changeouts and poor oil cleanliness. Filter elements were reaching terminal differential pressure every three weeks, driving more than $70,000 in annual filter expenses while still failing to meet the target ISO 17/15/12 cleanliness level. Elevated particle counts not only increased costs but also threatened unplanned downtime in a process where uninterrupted operation is critical.

This case study shows how upgrading to Donaldson Hy-Pro HP619L40-6EB filter elements dramatically improved both oil cleanliness and filter life. The mill achieved its cleanest oil to date—reducing dirt by 75% and improving ISO cleanliness to 16/14/12—while extending filter life up to 11 weeks. These improvements delivered $58,000 in annual savings, reduced maintenance intervention, and supported sustainability goals. The results demonstrate how advanced filtration and a shift away from time-based changeouts can significantly lower total cost of ownership while improving uptime and system reliability.
Ineffective Filters Lead to High Costs at American Paper Products Manufacturer - Process Improvement and DFE Rated Filter Elements

A routine cost reassessment at an American paper products manufacturer revealed rising expenses tied to frequent filter purchases and declining oil cleanliness in a critical main lube bearing system. While ISO cleanliness levels had not yet exceeded supplier limits, they were steadily trending upward, driving shorter filter life, increased labor, and growing concern over the risk of unplanned downtime. Recognizing the financial and reliability implications, the manufacturer engaged Donaldson Hy-Pro to evaluate the system and identify opportunities for improvement.

This case study details how replacing the existing filters with Donaldson Hy-Pro elements rapidly improved oil cleanliness and dramatically extended filter life. Within just one week, ISO codes dropped from 17/14/10 to 15/13/9, and element life doubled from 60 days to 120 days while maintaining superior cleanliness. The result was fewer filter changeouts, reduced labor, and a significant reduction in annual filter spend—from nearly $8,000 to under $3,400. The outcome demonstrates how effective filtration can lower total cost of ownership while improving reliability and maintenance confidence.
Paper Machine Lube Dry End Element - DFE Rated Filter Elements

A paper mill operating its dry end lubrication system was experiencing high filter consumption and sought a more effective filtration solution to improve oil cleanliness and reduce operating costs. OEM-specified filter elements were meeting basic requirements but offered limited service life and marginal cleanliness performance in a high-viscosity application with low differential pressure change limits. To improve reliability and profitability, the mill evaluated an upgraded filtration approach focused on cleaner oil and longer element life.

This case study details how upgrading to Donaldson Hy-Pro HP8314L39-6LB filter elements delivered measurable improvements in both cleanliness and durability. On-line particle counting showed up to a 93.7% reduction in damaging particles and a dramatic improvement in ISO cleanliness, while element life increased from approximately 41 days to as much as 65 days. These gains translated into reduced filter consumption, improved component protection, and greater system reliability—demonstrating how advanced filter element design can significantly reduce wear and extend maintenance intervals in critical paper machine lubrication systems.
Sawmill Hydraulic and Lube Oil Contamination Control

Unplanned downtime and rising maintenance costs were persistent challenges for a saw mill operating multiple large hydraulic systems with contaminated fluid. Poor fluid cleanliness led to fouled components, shortened equipment life, increased labor demands, and higher fluid consumption—creating a compounding financial burden. Recognizing that contamination control represented a major opportunity for improvement, the mill sought a more comprehensive strategy to protect equipment, stabilize operations, and reduce total cost of ownership.

This case study illustrates how a holistic, total systems cleanliness approach delivered rapid and measurable results. By upgrading to high-efficiency Donaldson Hy-Pro filter elements, installing desiccant breathers, and adding dedicated off-line filtration, the mill dramatically improved oil cleanliness across critical systems. ISO cleanliness codes improved by as much as five levels in under 30 days, significantly reducing contamination, extending fluid and component life, and minimizing downtime. The results demonstrate how addressing filtration, breathers, monitoring, and maintenance practices together can drive substantial gains in reliability, efficiency, and operating cost reduction.
V1 Mini Vacuum Dehydrator Successes

A paper mill facing severe water contamination across multiple lubrication systems needed a fast, effective way to remove moisture and avoid costly fluid replacement. Excess water in oil accelerates wear, depletes additives, and shortens component life, creating increased maintenance costs and reliability risks. In several applications throughout the mill—including calender lube systems, vacuum pump reservoirs, and reclaimed oil storage—water levels ranged from 1,400 ppm to as high as 20,000 ppm, well beyond acceptable limits for safe operation .

This case study demonstrates how deploying a Hy-Pro V1 vacuum dehydrator rapidly restored fluid condition and protected critical equipment. In each application, the V1 reduced water contamination to below 100 ppm—often in less than 72 hours—without interrupting operations or requiring oil replacement. By rotating a portable V1 unit among affected systems, the mill successfully extended fluid life, prevented premature component wear, and avoided unnecessary downtime and disposal costs. The results highlight the effectiveness of proactive water removal in preserving oil health and extending equipment life .
24 Hour Turn Around ISO Code Improvement with Donaldson Hy-Pro Filters

A U.S. paper mill faced a critical startup delay after an unexpected shutdown left the main lubrication system heavily contaminated and above acceptable ISO cleanliness limits. Despite deploying vacuum dehydrators and repeatedly changing finer inline filter elements, particle counts remained high, forcing daily filter replacements and putting production at risk. With the paper machine unable to restart until cleanliness targets were met, the situation demanded a fast, reliable solution.

This case study shows how Donaldson Hy-Pro applied a total systems approach to rapidly restore fluid cleanliness and enable a safe startup. By leveraging full-flow inline filtration with high-efficiency Donaldson Hy-Pro filter elements and real-time particle counting, the system’s ISO code dropped from a critical level to below the 16/14/10 target in just four hours. The machine was certified clean and ready for operation in less than 24 hours, and the system maintained excellent cleanliness for the next six months. The results highlight the value of advanced filtration, system-level diagnostics, and responsive technical support in preventing downtime and controlling costs in high-stakes manufacturing environments.

Plastics

PFHB Isolates Hydraulic Component Failures

A recycling plant operating a hydraulic bag shredder was experiencing repeated motor and pump failures caused by microscopic plastic contamination circulating through a closed-loop hydraulic system. These failures occurred as often as twice per year and triggered cascading damage as debris spread from one component to the next, resulting in repair costs exceeding $110,000 per incident—along with significant downtime and maintenance labor. Because the system required bi-directional flow, traditional filtration methods were unable to adequately protect critical components.

This case study shows how installing PFHB bi-directional filter housings and upgrading to Donaldson Hy-Pro DFE-rated Dualglass filter elements dramatically improved system reliability. By capturing contamination in both flow directions and isolating debris during component failures, the plant reduced failure rates by more than 50% and prevented secondary motor damage during pump failures. The result was more than $150,000 in annual savings, eliminated motor failures, and a more resilient hydraulic system—demonstrating the value of advanced, application-specific filtration in high-contamination recycling environments.
Plastic Injection Molding Element Upgrade

A ceramic injection molding facility was struggling with excessive contamination, varnish buildup, and premature oil replacement in its process vacuum pumps. ISO cleanliness levels had climbed to 22/20/14—far exceeding recommended limits—resulting in unexpected downtime and forcing costly synthetic oil, rated for over two years of service, to be replaced every six to eight months. The combination of dirt, water, and varnish contamination was undermining equipment reliability and driving unnecessary maintenance costs.

This case study details how installing a Donaldson Hy-Pro Compact Offline Filter (COF) with VTM media transformed fluid condition and asset performance. Within one month, ISO cleanliness improved to an exceptional 13/11/7, particle counts were reduced by 99.9%, water content was cut in half, and varnish potential dropped to condition-normal levels. These improvements allowed the facility to fully realize the value of its high-performance lubricant, extend oil and component life, and shift to a proactive maintenance strategy—delivering immediate savings and the potential for over $200,000 in long-term cost avoidance.

Steel Mills

Improving Rolling-Mill Lube-Oil Performance and Useful Life - VUD for Removal of Water

Steel rolling mills operate in extreme environments where high levels of water and particulate contamination are unavoidable, often leading to compromised lubrication, shortened oil life, and costly bearing failures. Even premium, high-demulsibility rolling-mill oils can quickly lose effectiveness when emulsified water and fine particles accumulate, reducing viscosity and damaging critical components. Left unchecked, these conditions force frequent oil decanting, premature oil replacement, and bearing failures that can cost tens of thousands of dollars per event.

This case study demonstrates how applying high-efficiency particulate filtration and vacuum dehydration dramatically improved lube-oil condition and system reliability in rolling-mill applications. By installing Donaldson Hy-Pro vacuum dehydration systems, mills rapidly reduced water levels from severe contamination to well below acceptable limits, stabilized viscosity, and eliminated recurring bearing failures. In addition, oil consumption was reduced by tens of thousands of gallons per year by ending routine decanting practices. The results show how proactive water and contamination control can extend oil life, protect bearings, reduce environmental impact, and deliver substantial operating cost savings in demanding steel-mill environments.
Steel Mill Hydraulic System - Cleaner Oil with BF Series High Flow High Efficiency Breathers and DFE Rated Filter Elements

A hot roll plate mill was seeking to improve the cleanliness and reliability of its high-pressure hydraulic system, which contained multiple filtration points across bulk tank recirculation, pump discharge, servo pilot, and return lines. Baseline on-line particle counting revealed contamination levels that threatened component life and system performance, prompting the mill to pursue a targeted filtration and contamination-control upgrade.

This case study shows how upgrading to Donaldson Hy-Pro G8 DFE-rated filter elements and installing high-efficiency breathers delivered dramatic improvements in fluid cleanliness. On-line monitoring confirmed up to a 99.9% reduction in damaging particles and a major improvement in ISO cleanliness codes across all particle sizes. These results translated into cleaner oil, reduced wear, and improved hydraulic reliability—demonstrating how strategic filter and breather upgrades can significantly extend component life and protect critical steel-mill hydraulic systems.
Steel Mill Lubricating Oil FSL System Upgrade

A steel mill was facing persistently poor oil cleanliness in a critical gear lubrication system, driving frequent oil testing, filter changes, and premature oil replacement. Despite ongoing preventive efforts, ISO cleanliness levels remained unacceptably high, increasing the risk of gear and bearing wear and raising the likelihood of costly unplanned shutdowns. The mill needed a more effective way to control contamination and extend the useful life of both the oil and mechanical components.

This case study shows how installing a Donaldson Hy-Pro FSL off-line filtration system dramatically improved gear oil cleanliness and system reliability. Over an extended evaluation period, the FSL system reduced particle contamination by up to 94% and stabilized ISO cleanliness at acceptable long-term levels. These improvements extended oil life, reduced maintenance intervention, and improved gear and bearing protection. The results demonstrate how dedicated off-line filtration can deliver significant cost savings and performance gains in demanding steel-mill gear lubrication applications.
Steel Mill Oscillator Hydraulic Filter Element Upgrade

A steel mill’s hydraulic oscillator system—responsible for precisely controlling the flow of molten steel into casting molds—was experiencing frequent filter changes and hydraulic fouling that threatened reliability and production quality. Operating with multiple filtration points across pump discharge, servo pilot, offline, and return lines, the system’s sub-standard fluid cleanliness was identified as a key contributor to performance issues and excessive maintenance.

This case study shows how upgrading to Donaldson Hy-Pro filter elements significantly improved hydraulic fluid cleanliness and system reliability. On-line particle counting confirmed up to a 75% reduction in damaging particles across critical size ranges, resulting in cleaner oil and reduced wear on sensitive servo components. The improved cleanliness translated into fewer filter replacements, more stable operation, and enhanced confidence in a mission-critical hydraulic system—demonstrating the impact of advanced filtration in high-pressure steel mill applications.
VUD Vacuum Dehydrator Steel Mill Lube Oil

A steel rolling mill was experiencing excessive water contamination in an 8,000-gallon lubrication system, with water levels reaching nearly 3% (29,000 ppm). To keep the system operating, the mill was decanting water daily—along with significant amounts of oil—resulting in annual oil consumption of more than 72,000 gallons. This practice increased operating costs, created environmental handling challenges, and contributed to leakage around roll stand gearbox seals, all while putting bearing reliability at risk .

This case study demonstrates how installing a Donaldson Hy-Pro Vacuum Dehydrator (VUD) rapidly transformed oil condition and operating economics. Water levels were reduced from over 29,000 ppm to below 400 ppm within two weeks, eliminating the need for daily decanting and stopping seal leakage. As a result, oil consumption was cut by approximately 35%, saving more than $200,000 annually while improving system reliability and reducing environmental impact. The outcome highlights the powerful role of vacuum dehydration in extending oil life, preventing failures, and delivering immediate, measurable cost savings in steel mill lubrication systems .