High-temp PALL replacement filter – cost-effective, equivalent performance.

1. Product Overview

Industrial hydraulic systems form the backbone of steel production and thermal power generation. 

From hot rolling mills and continuous casting lines to turbine lubrication and electro-hydraulic control systems, 

these operations depend on reliable fluid power to maintain continuous, efficient production. At the heart of

 these systems lies a critical but often overlooked component – the hydraulic filter element.

The quality and performance of this component directly influence equipment reliability, maintenance intervals,

 and operational costs. Contaminated hydraulic fluid, if left unfiltered or improperly filtered, accelerates wear on

 servo valves, pumps, and actuators, leading to unplanned downtime, costly repairs, and production losses.

Our Glass Fiber Folded Replacement Filter Element, engineered as a direct interchange for PALL HC/UE series 

filters (including HC9600, HC8300, UE319, and UE619 series) , addresses these challenges through advanced 

media technology, rugged construction, and precise dimensional compliance. This product is specifically

 designed for the demanding environments found in steel mills and power plants – where high temperatures, 

abrasive contaminants, and continuous operation place exceptional stress on filtration systems.

As an independent aftermarket manufacturer, we offer these replacement elements at 40%–60% of the cost of

 genuine PALL parts, without compromising filtration efficiency, service life, or system compatibility. 

Each element undergoes stringent quality control, ensuring that plant operators receive a reliable,

 cost-effective solution for maintaining hydraulic fluid cleanliness and protecting critical assets.

2. The Challenges of Steel & Power Plant Hydraulic Systems

Hydraulic systems in steel and power generation facilities operate under some of the most severe conditions

 encountered in industrial applications. Understanding these challenges is essential to selecting the correct

 filtration solution.

Elevated Operating Temperatures: Continuous oil temperatures in hot rolling mills and power plant EH systems

 typically range from 90°C to 120°C, with instantaneous thermal spikes reaching 130–150°C due to furnace radiation, 

load surges, or cooling system limitations. At these temperatures, standard filter media may experience resin 

degradation, fiber embrittlement, and accelerated aging – leading to premature failure and contamination bypass.

Complex Contaminant Profiles: Hydraulic oil in these environments accumulates a diverse range of 

pollutants – iron oxide particles from pipe scale, metal wear debris from pumps and valves, 

varnish and oil sludge from thermal degradation, sulfide corrosive byproducts, and fine rust fragments from 

moisture ingress. This mixture of abrasive, adhesive, and corrosive contaminants places exceptional demands 

on filter media structure and chemistry.

Pressure Fluctuations and Flow Shocks: Cyclic pressure variations, intermittent high-flow impacts, and load-induced 

surges create mechanical stress on filter elements. Media with insufficient structural strength may collapse,

 pleats may deform, and seals may fail under these dynamic conditions.

Stringent Cleanliness Requirements: Modern hydraulic systems incorporate precision components such as servo valves,

 proportional valves, and high-response actuators, which require oil cleanliness maintained to ISO 4406 

standards (typically ≤16/13/10) . Even brief excursions above recommended cleanliness levels can cause scoring 

of valve spools, sticking of control elements, and loss of positioning accuracy.

Conventional single-layer paper elements or low-grade glass fiber media cannot reliably withstand these conditions. 

They exhibit rapid differential pressure rise, premature clogging, media delamination, and sealing failure – ultimately 

allowing contaminants to pass through and damage system components. Only advanced multi-layer composite media,

 coupled with high-temperature accessories and precision construction, can provide the durability and performance 

required in these severe service applications.

3. Advanced Media Technology – Multi-Layer Gradient Glass Fiber (Upgraded)

The filtration performance of any element is primarily determined by its media. Our upgraded replacement 

filter elements utilize multi-layer gradient borosilicate glass fiber media, engineered specifically for high-temperature, 

high-contaminant industrial applications.

Gradient Pore Structure: The gradient pore structure operates on a stepwise filtration principle:

· Outer coarse fiber layer (280–350g/m²): Captures large metal debris and particulate contaminants (>20μm), 

preventing rapid surface blinding.

· Intermediate transition layer (200–260g/m²): Adsorbs oil sludge, oxidized colloids, and fine suspended material.

· Inner dense fine layer (180–240g/m²): Intercepts micron and sub-micron particles down to the rated size, 

ensuring filtration precision is maintained throughout service life.

Performance Advantages: This layered architecture distributes contaminant loading across the entire media

 depth rather than concentrating it on the surface. As a result, the element achieves:

· Higher dirt-holding capacity: 1,500–2,100 g/m² (20%–30% higher than previous generation)

· Lower initial differential pressure: ≤0.025 MPa at rated flow

· Extended service intervals: Up to 50% longer than conventional single-layer media

· Beta ratio: βₓ ≥ 2000 (≥99.95% efficiency at rated size) per ISO 16889

Quality Compliance: All media formulations comply with ISO 16889 multipass filtration test standards and 

ISO 3724 flow fatigue test requirements. The borosilicate composition offers excellent chemical stability, 

resisting degradation from water ingress, acidic oxidation byproducts, and additive depletion commonly 

encountered in long-service hydraulic systems.

Qualification Testing: Each media grade is subjected to rigorous qualification testing, including high-temperature 

aging (1000+ hours), tensile strength retention measurement (>90% retention), and filtration efficiency verification 

before and after thermal exposure. This ensures predictable performance and reliable contaminant control 

throughout the rated service life.

4. Temperature-Graded Selection – Matching Media to Working Conditions (Upgraded)

Recognizing that steel and power plant applications cover a wide range of thermal conditions, 

we offer three temperature-graded media options. This allows plant engineers to select the filter element 

best suited to their specific operating parameters, optimizing both performance and service life.

---

Grade 1 – Standard Medium-Temperature Media

Parameter Specification

Continuous operating temp. ≤100°C

Peak tolerance 105°C (instantaneous)

Media structure 3-layer gradient borosilicate fiber

Resin type Low-temperature cross-linked phenolic

Resin thermal deformation 112°C

Beta ratio (βₓ) ≥200 (99.5% efficiency)

Dirt holding capacity 1,300–1,500 g/m²

Effective filtration area 3–4× flat sheet media

Seals NBR nitrile rubber

Support core Galvanized carbon steel

End-cap adhesive Polyurethane

Typical applications Cold rolling auxiliary stations, low-load power plant lube circuits

---

Grade 2 – Reinforced High-Temperature Media (Upgraded)

Parameter Specification

Continuous operating temp. 100°C – 120°C

Peak tolerance 130°C (≤30 minutes)

Media structure 4-layer thickened gradient borosilicate

Resin type High cross-linking heat-resistant phenolic

Resin solid content 14%–16%

Resin thermal deformation 138°C

Safety margin 18°C above continuous limit

Beta ratio (βₓ) ≥1000 (99.9% efficiency)

Dirt holding capacity 1,700–2,000 g/m² (+25% vs. Grade 1)

Strength retention (1000h cyclic 110–130°C) ≥91%

Efficiency attenuation (same period) ≤1.8%

Surface treatment Calendered dense isolation layer

Seals Standard FKM fluororubber

Support core 304 stainless steel (≥1.2mm)

End-cap adhesive Fluorine-epoxy hot-melt (peel strength ≥50N/cm)

Typical applications Hot rolling mills, conventional power plant EH systems

Market coverage ≈90% of steel & power main hydraulic stations

---

Grade 3 – Ultra-High Temperature Custom Media (Upgraded)

Parameter Specification

Continuous operating temp. ≤140°C

Peak tolerance 150°C (≤20 minutes)

Media structure Modified high-temp glass fiber + PTFE isolation film

Surface treatment Full fluorination anti-acid, anti-oxidation

PTFE stability <260°C (effectively isolates acidic byproducts)

Beta ratio (βₓ) ≥2000 (99.95% efficiency)

Dirt holding capacity 1,900–2,200 g/m² (+45% vs. Grade 1)

Strength retention (1200h at 140°C in oxidized oil) ≥96%

Embrittlement/perforation None detected

Seals Modified full-fluorine FKM

Support core 316L stainless steel (molybdenum-bearing, corrosion-resistant)

End-cap High-temp integral injection-molded

Typical applications Furnace-front cylinder systems, heavy roughing mills, boiler main actuator stations

Required measures Auxiliary cooling, average temp ≤130°C, 30% shorter replacement interval

5. Complete High-Temperature Accessory Matching (Upgraded)

A filter element is only as reliable as its weakest component. In high-temperature applications, seals, adhesives,

 support structures, and bypass valves must all perform at the same level as the media itself. Our replacement 

elements ensure all accessory components are matched to the selected media grade, eliminating weak points 

that could compromise system reliability.

Sealing Systems – Three Seal Grades:

Grade Seal Material Continuous Range Peak Tolerance Key Feature

Grade 1 NBR nitrile rubber -40°C ~ +100°C 110°C Cost-effective for standard service

Grade 2 Standard FKM fluororubber -20°C ~ +120°C 130°C Volume swell <3% after 1000h

Grade 3 Modified full-fluorine FKM -20°C ~ +140°C 150°C Anti-oxidation molecular chain structure

End-Cap Bonding:

Grade Adhesive Type Max Continuous Temp. Peel Strength Performance Note

Grade 1 Polyurethane 110°C ≥40 N/cm Standard heat resistance

Grade 2 & 3 Fluorine-epoxy hot-melt 145°C ≥50 N/cm Stable under cyclic thermal shock, no de-bonding

Support Cores:

Grade Material Wall Thickness Construction Corrosion Resistance

Grade 1 Galvanized carbon steel ≥1.0mm Seamless rolled Standard

Grade 2 304 stainless steel ≥1.2mm Seamless rolled integral Excellent

Grade 3 316L stainless steel ≥1.2mm Seamless rolled integral Superior (chloride-resistant)

Bypass Valves:

· All elements incorporate stainless steel spring valve cores

· Valve gaskets temperature-matched to selected seal grade

· Standard 3bar ±10% set point (fully aligned with original PALL parameters)

· FKM valve gaskets maintain stable opening pressure across -10°C to 130°C range

6. Application Selection Guidelines (Upgraded)

---

Application A – Cold Rolling Auxiliary Hydraulic Station

Parameter Specification

Oil temperature ≤100°C continuous, peaks ≤105°C

Recommended media Grade 1 (3-layer, 1,300–1,500 g/m² capacity)

Seals NBR nitrile rubber

Support core Galvanized carbon steel

Compatible filters PALL HC/UE series (HC9600, HC8300, UE319)

Additional measures Heat insulation baffles, weekly tank bottom water drainage

---

Application B – Hot Rolling Mill or Power Plant EH System

Parameter Specification

Oil temperature 100–120°C continuous, 125–130°C peaks (<30 min)

Recommended media Grade 2 (4-layer, 1,700–2,000 g/m² capacity, βₓ≥1000)

Seals Standard FKM fluororubber

Support core 304 stainless steel (≥1.2mm)

Compatible filters PALL HC series pressure filters

Coverage ≈90% of steel & power main hydraulic stations

Additional measures Cooling system monitoring, differential pressure recorded per shift

---

Application C – Furnace-Front or Boiler Actuator Station

Parameter Specification

Oil temperature 120–140°C continuous, 140–150°C peaks

Recommended media Grade 3 (PTFE-coated, 1,900–2,200 g/m² capacity, βₓ≥2000)

Seals Modified full-fluorine FKM

Support core 316L stainless steel (≥1.2mm)

Compatible filters PALL UE series high-pressure units

Additional measures Auxiliary coolers mandatory, average temp ≤130°C, 30% shorter replacement interval

7. Economic Benefits Summary

Benefit Area Advantage

Procurement cost 40%–60% savings vs. genuine PALL parts

Filtration performance Equivalent or superior (βₓ≥2000, NAS 5–6 cleanliness)

Service life Extended by 20%–50% via high-capacity gradient media

Delivery lead time 7–15 working days vs. 8–12 weeks for genuine parts

Interchangeability 100% 1:1 dimensional compliance – no housing modification

Customization OEM/ODM supported (logo, media, dimensions)

Documentation Full EN 10204 + ISO 16889 test reports for export

8. Conclusion

The selection of replacement filter elements for steel and power plant hydraulic systems must be based on 

three core operating parameters: oil temperature, system flow rate, and upstream contamination load.

Correct matching of media grade (Grade 1/2/3), sealing materials (NBR/FKM/Full-FKM), and structural

 components (galvanized/304/316L support cores) to actual operating conditions ensures:

· Oil cleanliness maintained at ISO 4406 ≤16/13/10 (NAS Class 5–6)

· 1:1 direct interchangeability with original PALL housings – no modifications required

· 40%–60% cost savings with equivalent or superior performance

· Extended service intervals and reduced unplanned downtime

Choose the right grade for your application and secure your hydraulic system reliability at a lower cost.