Hydraulic Oil Filter Elements – Models 21FC1421-140×400/14 & 21FC5121-110×160/10

Two high-performance pleated hydraulic oil filter elements from the same 21FC industrial filter family, engineered for pressure-line, return-line, and lubrication-circuit duties across steam turbines, metallurgical rolling mills, injection molding machines, compressor lube systems, and mobile hydraulic equipment. The model coding denotes dimensional envelope and micron grade: 21FC1421-140×400/14 = 140 mm OD × 400 mm length, 14 µm grade; 21FC5121-110×160/10 = 110 mm OD × 160 mm length, 10 µm grade . Both use imported glass-fiber media qualified to ISO 16889 multi-pass testing, delivering 98 % filtration efficiency and 2000 h service life in standard hydraulic duty .

Key Features

• 21FC1421-140×400/14: 140 mm OD × 400 mm length, 14 µm grade, glass-fiber media, 98 % efficiency, 2000 h service life, larger dirt-holding capacity for extended service intervals

  
  

• 21FC5121-110×160/10: 110 mm OD × 160 mm length, 10 µm grade, glass-fiber media, 98 % efficiency, 2000 h service life, compact envelope for space-constrained housings

  
  

• Both: pleated (fold-style) construction, galvanized carbon steel end caps, carbon steel perforated core, spray-net protective layers

  
  

• Configurable media: glass-fiber, HV filter paper, stainless steel wire mesh

  
  

• Configurable micron grades: 1 / 3 / 5 / 10 / 15 / 20 / 25 / 40 / 50 / 80 / 100 / 150 / 200 µm

  
  

• NBR seals standard; Viton (FKM) optional

  
  

• Collapse pressure rating 21–210 bar (1.0 / 2.0 / 16.0 / 21.0 MPa structural options)

  
  

• Working medium: mineral hydraulic oil, phosphate ester, emulsion, water-glycol

  
  

• Operating temperature: -30 °C to +110 °C (hydraulic trim); 0–100 °C typical

  
  

Technical Specifications

Application Guidance

21FC1421-140×400/14 – Large-format pleated element for pressure-line and return-line filtration on steam turbine lube systems, rolling-mill hydraulic stands, and heavy industrial power units . The 140 × 400 mm envelope and 14 µm grade deliver high dirt-holding capacity, extending service intervals in continuous-process industries (thermal power, nuclear power, metallurgy) where unplanned shutdown is costly . Also deployed in textile polymer melt filtration, compressor protection, and compressed-gas oil-water separation .

21FC5121-110×160/10 – Compact pleated element for return-line, pressure-line, and bypass filtration where housing space is limited . The 110 × 160 mm envelope with 10 µm grade suits auxiliary hydraulic loops, lubrication system bypass circuits, and mobile equipment hydraulic returns . Configurable to finer grades (1–5 µm) for servo-valve protection or coarser grades (20–40 µm) for pre-filtration .

📌 FC-Series family note: The 21FC prefix denotes a fold-style (pleated) cartridge element for hydraulic and lubrication systems — covering bypass, inline (suction, pressure, return), and fill filtration . The numeric suffix encodes OD × length / micron grade. Both elements are widely applied across steam turbines, rolling mills, injection molding machines, compressor lube circuits, and industrial hydraulic power units .

Fluid Compatibility

• Mineral hydraulic oil (ISO HM, HV)

  
  

• Phosphate ester (HFDR) — Viton seals recommended

  
  

• Emulsions and water-glycol (HFC) — NBR acceptable; Viton recommended

  
  

• Turbine lube oil, gear oil, compressor oil

  
  

• Not for strong solvents or corrosive chemicals

  
  

Installation & Service

1. Shut down the equipment; relieve system pressure to 0 bar and isolate the filter housing.

   
   

2. Open the housing cover, withdraw the spent cartridge by its center tube.

   
   

3. Inspect the housing interior, bypass spring (if fitted), and seal grooves.

   
   

4. Seat the new element — confirm flow direction (Outside → Inside). Renew all O-rings / seals.

   
   

5. Close the housing, torque bolts evenly. Bleed air at the bleed port.

   
   

6. Restart and check for leaks at operating pressure.

   
   

7. Replace per clogging indicator (terminal ΔP 0.35–0.5 MPa) or 2000 h service interval . In high-contamination environments, monitor via differential pressure gauge and replace when the indicator triggers.

   
   

⚠️ Glass-fiber and paper elements cannot be cleaned — always replace with new; only stainless steel mesh elements may be soaked and blown clean. A clogged element left in service causes accelerated wear, overheating, and abnormal actuator response. Over 70 % of hydraulic system failures originate from fluid contamination.

Quality Assurance

• ISO 16889 – Multi-pass filtration performance (β-ratio, dirt-holding capacity, ΔP)

  
  

• ISO 2941 – Collapse/burst resistance (21–210 bar)

  
  

• ISO 2942 – Manufacturing integrity (bubble point)

  
  

• ISO 2943 – Media/fluid compatibility

  
  

• ISO 3968 – Differential pressure vs. flow rate

  
  

• ISO 9001 – Quality management system certified manufacturing

  
  

Ordering

Specify 21FC1421-140×400/14 (140 × 400 mm, 14 µm) or 21FC5121-110×160/10 (110 × 160 mm, 10 µm) together with:

• Required micron grade (1 / 3 / 5 / 10 / 15 / 20 / 25 / 40 / 50 / 80 / 100 / 150 / 200 µm)

  
  

• Media type (glass-fiber / HV paper / stainless steel mesh)

  
  

• Collapse pressure class (21 / 60 / 160 / 210 bar)

  
  

• Seal material (NBR / Viton)

  
  

• End cap material (carbon steel / stainless steel / aluminum / nylon)

  
  

Provide your existing element's dimensions or the host machine model and current OEM part number for cross-reference confirmation. Custom dimensions and media grades are available on request.

All values nominal; 21FC1421-140×400/14 documented at 140 × 400 mm, 14 µm, glass-fiber, 21 MPa working pressure, -30 °C to +110 °C, general hydraulic oil / phosphate ester / emulsion / water-glycol . 21FC5121-110×160/10 documented at 110 × 160 mm, 10 µm, glass-fiber, 98 % efficiency, 2000 h service life . Both elements belong to the 21FC fold-style cartridge family for hydraulic and lubrication filtration . Confirm OD, length, ID, end-cap pattern, and seal interface against your existing element or housing drawing before installation. Select micron grade to match circuit position: 1–5 µm for servo valves, 5–10 µm for high-pressure piston pumps, 10–25 µm for general hydraulic, 20–40 µm for return-line coarse filtration.