In-Line High-Pressure Oil Filter — SLC Series
The SLC in-line pressure oil filter is a compact, die-cast housing for centralized oil lubrication and recirculation circuits. Disposable sintered metal elements (1″ or 3″ depth options) remove solid particles before oil reaches pumps, PDI injectors, bearings, or spindles—extending component life and stabilizing flow through narrow metering orifices.
Filtration: nominal 3, 12, or 25 µm grades (also catalogued as 25 µm and 125 µm coarse protection on some element codes—confirm P/N on quote). Max pressure: 300 psi (~21 bar) continuous service class for this SLC body. Inlet: 1/2 NPT. Bowl removes by hand for quick element inspection without special tools.
Install on pump discharge, return line before reservoir, or branch feed to critical zones. Pair with lube oil pumps, single-line PDI systems, and circulating oil pumps. For grease circuits, use ELS grease filter (150 µm, 25 MPa class)—do not assume SLC oil housing ratings on grease MPa lines without engineering approval.
- SLC Filter Specifications
- What the Filter Protects
- Typical Installation Points
- Element Change Interval
- Oil Filter vs Grease Filter
| Parameter | Specification |
|---|---|
| Element type | Disposable porous / sintered metal |
| Element depth | 1″ or 3″ (two housing sizes) |
| Micron ratings | 3, 12, 25 µm nominal (confirm coarse 125 µm P/N if required) |
| Max pressure | 300 psi |
| Inlet thread | 1/2 NPT |
| Service | Continuous flow or cyclic PDI operation |
| Housing | Die-cast, hand-removable bowl |
- Pump elements — scoring from sand, scale, and wear chips
- Injector nozzles — 0.2–0.6 mm orifices in single-line oil systems
- Bearing surfaces — abrasive particles accelerate fatigue and overheating
- Heat exchangers / coolers — fouling from ingression on open reservoirs
- After pump, before divider/injectors — primary plant protection
- On fill line — when transferring oil from bulk tank to machine reservoir
- Recirculation loop — before oil re-enters bearing gallery on machine tools
Replace when pressure differential rises vs clean baseline, on visual darkening of element, or at PM interval (often 500–2000 h depending on ingression). Finer 3 µm elements protect spindles but clog faster in dirty plants—use 25 µm upstream and fine filter at machine if needed.
| Filter | Media | Pressure class | Circuit |
|---|---|---|---|
| SLC oil (this page) | 3–25 µm sintered | 300 psi | Oil PDI / circulation |
| ELS grease | 150 µm strainer | 25 MPa | NLGI grease progressive / dual-line |
A SLC housing with sintered element installed in the oil line to remove particles before lubricant reaches machine components—part of industrial centralized lubrication, not engine spin-on filters alone.
Nominal 3, 12, and 25 µm elements; quote may list 25 µm and 125 µm coarse codes for specific SLC P/N—confirm on BOM.
300 psi for standard SLC in-line bodies—size circuit accordingly; high-MPa grease lines need grease-rated filters.
1/2 NPT inlet—use compatible pipe and hose and adapters
Based on ΔP, visual inspection, and oil sample—dirty environments need shorter intervals; keep spare 1″/3″ elements on PM cart.
Yes—hand-removable bowl for quick element swap; isolate and depressurize line before opening.
Designed for oil lubrication. Grease circuits use different strainers rated for NLGI and MPa class.
Ingression at breather, refill, and wear debris still circulate—clean oil maintains injector timing and bearing film thickness on PDI systems.