Hydraulic Multi-Pass Test Bench
Category：Filter Cartridge Filtration Tester
Introduction
Application
The Hydraulic Multi-Pass Test Bench is a precision testing system designed to evaluate the filtration performance of hydraulic filters, oil filters, fuel filters, and other fluid filtration materials.
It adopts the online particle counting method to determine filter efficiency (filtration accuracy), contaminant holding capacity (dirt capacity and service life), and pressure drop characteristics under continuous contamination conditions.
In simple terms, the system injects test dust into the filter oil circuit continuously, and real-time particle counters measure upstream and downstream contamination levels to evaluate filtration performance dynamically.
Applicable Standards
The system complies with both international and Chinese filtration performance standards, including:
GB/T 18853 — 2002 Hydraulic filters — Multi-pass method for evaluating filtration performance
ISO 16889 — 2007 Hydraulic filters — Multi-pass method for evaluating filtration performance
ISO 4548-12 — 1997 Full-flow lubricating oil filters for internal combustion engines — Part 12: Filtration efficiency and contaminant capacity by particle counting
ISO/DIS 19438 — 2000 Diesel and gasoline fuel filters — Filtration efficiency and contaminant capacity by particle counting
Test Objects
Hydraulic filters
Engine oil filters
Fuel filters
Hydraulic and oil filtration media
Test Items
Filtration efficiency (filtration precision)
Contaminant holding capacity (dirt capacity / service life)
Flow-pressure drop characteristics
Technical Parameters
| Parameter | Unit | Value / Specification |
|---|---|---|
| Test medium | – | YH-15 or equivalent oil, or customer-specified oil |
| Medium viscosity | mm²/s | 13.2 at 40°C |
| Flow range | L/min | 1 – 100 |
| Flow section 1 | L/min | 1 – 10 |
| Flow section 2 | L/min | 10 – 30 |
| Flow section 3 | L/min | 30 – 100 |
| Minimum system pressure | MPa | 0.6 |
| Maximum system pressure | MPa | 2.0 |
| Maximum differential pressure | MPa | 1.6 |
| Differential pressure sensor | KPa | 0 – 200 |
| Contamination injection flow rate | mL/min | 50 – 300 adjustable (standard 250) |
| Online dilution ratio | – | 1:10 (sampling flow 20 mL/min) |
| Temperature control | °C | 40 ± 2 |
| Test oil tank volume | L | 50 (dual cone design) |
| Contaminant injection tank | L | 40 |
| Auxiliary tank | L | 100 |
| Particle counter | – | KZD-3A (Tianjin), 32 channels (16 upstream + 16 downstream) |
| Control mode | – | Fully automatic programmable control |
| Heating method | – | Silicone rubber electric heating |
| Cooling method | – | Refrigeration unit |
| Frame material | – | Aluminum profile, stainless steel panels |
| Pipeline material | – | 304 stainless steel |
| Filter media fixture | cm² | 200 per set |
| Spin-on filter fixture | – | One set |
| Rated power | kW | 28 |
| Power supply | – | 3-phase AC 380V / 50Hz |
| Test bench dimensions (L×W×H) | mm | 3200 × 1500 × 2000 |
| Control cabinet dimensions (L×W×H) | mm | 800 × 700 × 1800 |
Measurement Accuracy and Test Conditions
| Parameter | Unit | Reading Accuracy (±) | Permissible Variation (±) |
|---|---|---|---|
| Pressure drop | kPa | 5% | – |
| Upstream contamination concentration | mg/L | – | 10% |
| Injection flow rate | mL/min | 2% | 5% |
| Test flow rate | L/min | 2% | 5% |
| Sensor flow rate | L/min | 1.5% | 3% |
| Temperature | °C | 1°C | 2°C |
| Time | s | 1s | – |
| System volume | L | 2% | 5% |
Note: The total flow deviation between two sensors (including sensor drift) shall be within 10%.
Functional Advantages
Fully Automated Control: PLC-based automatic testing with real-time monitoring and report generation
High Measurement Accuracy: Integrated online particle counter ensures reliable filtration efficiency evaluation
Comprehensive Testing Capability: Covers efficiency, dirt capacity, and pressure drop in one integrated platform
Precise Thermal Management: Automatic heating and cooling system maintains constant oil temperature
Robust Construction: Stainless-steel pipeline and aluminum frame for long service life and contamination-free operation
Modular Design: Adaptable fixtures for both filter elements and spin-on filters
