HF4P Series
Inline Filters
5000 PSI • Up to 120 GPM

Hydac_HF4P Series Filter


  • Meets HF4 automotive standard.
  • Non-welded housing design reduces stress concentrations and prevents fatigue failure.
  • Inlet/Outlet port options include SAE straight thread O-ring boss, BSPP and subplate mounting to allow easy installation without costly adapters.
  • O-ring seals are used to provide positive, reliable sealing. Choice of O-ring materials (Nitrile, Fluoroelastomer, EPR) provides compatibility with petroleum oils, synthetic fluids, water-glycols, oil/water emulsions, and high water base fluids.
  • Screw-in bowl mounted below the filter head requires minimal clearance to remove the element for replacement, and contaminated fluid cannot be washed downstream when element is serviced.

Technical Details

Mounting Method 4 Mounting Holes
Port Connection SAE-24, 1-1/2˝ BSPP, 1-1/2˝ SAE
Flange Code 61, 1-1/2˝ SAE Flange
Code 62, Manifold Mount
Flow Direction
Inlet: Side Outlet: Side
(opposite each other)
Construction Materials
Head, Cap

Ductile Iron
Flow Capacity


50 gpm   (189 lpm)
100 gpm (378 lpm)
120 gpm (454 lpm)
Housing Pressure Rating
Maximum Operating Pressure
Proof Pressure
Fatigue Pressure
Burst Pressure

5000 psi      (345 bar)
7500 psi      (517 bar)
5000 psi      (345 bar) @ 1 million cycles
15,000 psi (1040 bar)
Element Collapse Pressure Rating

3000 psid (207 bar)
150 psid     (10 bar)
Fluid Temperature Range -22° to 250°F (-30° to 121°C)
Fluid Compatability
Compatible with all petroleum oils and synthetic fluids rated for use with Fluoroelastomer or Ethylene Propylene seals. Contact HYDAC for information on special housing and element constructions available for use with water glycols, oil/water emulsions, and HWBF.
Indicator Trip Pressure
ΔP = 29 psid (2 bar) - 10% (optional)
ΔP = 72 psid (5 bar) - 10% (standard)
ΔP = 116 psid (8 bar) - 10% (optional on bypass)
Bypass Valve Cracking Pressure
ΔP = 43 psid (3 bar) + 10% (optional)
ΔP = 87 psid (6 bar) + 10% (standard)
Non Bypass Available