Pall HC7500SDZ4Z Replacement Filter Element — Cross-Reference & Specifications
Hydrafil Part Number: BF-PAL-431599-L4-1MV | Ships same day from Detroit, MI | OEM-equivalent performance
The Pall HC7500SDZ4Z carries the most demanding dual specification in the HC7500 compact form factor: 1-micron ultra-fine glass media combined with Viton (fluorocarbon) seals for precision circuits where both exceptional contamination control and chemical resistance are required simultaneously. This combination — 1µm filtration and Viton seals — is the correct selection for servo valve supply filtration on equipment running phosphate ester fluids (HFD-R, Skydrol-type), high-temperature mineral oil where Buna-N would degrade, or any precision circuit where fluid chemistry and cleanliness requirements converge at the strictest end of the specification range. The compact 6.9 in L4 body maintains a minimal installation footprint for space-constrained servo installations in aircraft ground support equipment, precision test bench systems, and high-performance industrial machinery.
Dimensional Specifications
The SDZ4Z fits the short-body (L4) HC7500 housing only — verify housing length before ordering; 1µm media produces higher differential pressure than coarser elements, and an incorrectly seated element will bypass contamination rather than filter it.
| Specification | Value |
|---|---|
| Outer Diameter (Top) | 5.06 in |
| Outer Diameter (Bottom) | 5.06 in |
| Element Length | 6.9 in |
| Thread Size | 1.5 - 16 |
| Collapse Rating | 100 psid |
Media & Construction
The BF-PAL-431599-L4-1MV pairs ultra-fine microglass fiber media with Viton elastomers — the combination required when both particle size and fluid chemistry demand the highest available specification in this housing family.
- Filtration Media: Microglass Fiber Media — ultra-dense fiber construction required to achieve 1µm Beta-rated capture efficiency; removes sub-micron particles that pass through all coarser HC7500 variants, protecting servo spool/sleeve clearances as tight as 1–4µm from the particles most responsible for valve sticking and internal leakage
- Seal Material: Viton (Fluorocarbon) — rated for phosphate ester (Skydrol, HFD-R), polyol ester, and high-temperature mineral oil to 400°F; mandatory when fluid chemistry would cause Buna-N swelling, dissolution, or seal failure that would bypass ultra-fine filtration and contaminate the servo circuit
- End Caps: Corrosion Resistant Steel — dimensional stability across the elevated temperatures Viton seals are selected for; maintains proper media pack compression
- Center Tube: Corrosion Resistant Steel — structural support critical at 1µm, where flow resistance is highest and cold-start differential pressure can stress the element assembly significantly
Filtration Performance Rating
At 1µm with Viton seals, the SDZ4Z delivers the most stringent specification available in the HC7500 / 50-AT series. Beta 200/1000 values across ISO 16889 multi-pass testing confirm that sub-micron particle capture is consistent, not intermittent — the requirement for protecting servo valves in phosphate ester or high-temperature systems where both a contamination failure and a seal failure would simultaneously damage tight-tolerance components and contaminate the system with degraded elastomer material.
The SDZ4Z’s 1µm Viton compact configuration is the precision-grade specification for servo valve protection in chemically aggressive or high-temperature hydraulic circuits — the only HC7500 variant that simultaneously addresses the sub-micron cleanliness requirements of servo components and the chemical compatibility demands of phosphate ester and high-temp fluid systems.
| Rating | Value |
|---|---|
| Beta Ratio (Bx) | 200 |
| Beta Ratio Bx[c] | 1000 |
ISO Standards Compliance
Manufactured to the full suite of ISO hydraulic filter standards for documented OEM-equivalent performance.
| ISO Standard | What It Tests |
|---|---|
| ISO 2941 | Collapse & burst resistance |
| ISO 2942 | Fabrication integrity & bypass valve function |
| ISO 2943 | Material compatibility with hydraulic fluids |
| ISO 3724 | Flow fatigue characteristics |
| ISO 3968 | Pressure drop vs. flow rate characteristics |
| ISO 16889 | Multi-pass performance (Beta ratio methodology) |
About the Pall HC7500SDZ4Z
The HC7500SDZ4Z is reserved for the most demanding precision hydraulic applications — systems where both servo-valve cleanliness and phosphate ester or high-temperature fluid compatibility are required in the same installation. It is most commonly specified in aircraft ground support hydraulic test equipment using Skydrol-compatible fluid, industrial simulation and test bench systems with strict servo positioning requirements running fire-resistant fluid, and high-performance military or aerospace ground equipment where both 1µm cleanliness levels and Viton chemical resistance are non-negotiable engineering requirements. The compact L4 body makes this the correct choice for space-constrained installations where the full SDZ8Z long-body element would not fit.
Why Order from Hydrafil?
- OEM-equivalent performance at a lower cost per element
- Manufactured and sourced in the USA — Detroit, Michigan facility
- Same-day shipping on in-stock elements
- 200,000+ filter cross-references available
- Technical support: +1 (313) 915-4120
Questions? Call (313) 915-4120 or email sales@hydrafil.com
Pall and HC7500SDZ4Z are trademarks of their respective owners, referenced here solely for cross-reference and compatibility identification purposes.