CACA-LIN Cartridge Valve
Brand: Sun Hydraulics (USA)
Type: 3-port externally vented pilot-operated counterbalance cartridge valve, also known as load control valve or motion control valve.
1. Model Code Explanation (CACA-LIN)
- CAC: Counterbalance valve series, 3-port & externally vented, T-11A cavity
- A: Standard version
- L: Pilot ratio 3:1
- IN: Standard pressure and flow rating
2. Main Technical Parameters
- Cavity: T-11A
- Max flow rate: 60 L/min (15 gpm)
- Max working pressure: 280 bar (4000 psi)
- Pressure adjustment range: 14 – 280 bar; Fully clockwise ≈ 14 bar (200 psi)
- Pilot ratio: 3:1 (Pressure reduction via Port 3)
- Check valve cracking pressure: 1.7 bar (25 psi)
- Drain type: External drain (Port 4 to tank/atmosphere), free from back pressure interference
- Installation torque: 41 – 47 Nm (30 – 35 lbf·ft)
- Weight: Approx. 0.2 kg
3. Port Definition (3 working ports + External Drain Port 4)
- Port 1: Load port (Connect to cylinder or motor)
- Port 2: Directional valve port (Connect to directional control valve)
- Port 3: Pilot control port
- Port 4: External drain port (Independent drain for spring chamber)
4. Operating Principle
1. Forward flow (Port 2 → Port 1): The check valve opens for free flow with low resistance.
2. Reverse flow (Port 1 → Port 2): Main valve remains closed to balance load and prevent load runaway.
3. Pilot control (Port 3): Applied pilot pressure reduces main valve cracking pressure at a 3:1 ratio, enabling smooth load lowering.
4. External drain (Port 4): The spring chamber drains independently. Back pressure at Port 2 will not affect the pressure setting for stable operation.
5. Key Features (Compared with CBGA-LHN)
- Compact size with T-11A cavity; rated flow 60 L/min (CBGA-LHN: 240 L/min)
- External drain design: Setting pressure is not affected by back pressure at Port 2, ideal for circuits with high back pressure
- Zero internal leakage for reliable load holding
- Reset accuracy: ≥ 85% of set pressure for excellent stability
6. Typical Applications
- Construction machinery: Boom of mini excavators, tilt cylinders of forklifts, luffing cylinders of light-duty cranes
- Industrial hydraulics: Lifting platforms, telescopic booms, synchronous servo systems
- Working conditions: Medium-low pressure, medium-low flow, high vibration, precise load balancing and load holding required
7. Installation & Commissioning Guidelines
- Set pressure: No less than 1.3 times the maximum load pressure to avoid pressure drift
- Adjustment: Turn clockwise to decrease pressure; turn counterclockwise to increase pressure
- Back pressure: Back pressure at Port 2 has no impact on pressure setting due to external drain design
8. Interchangeable Models
- CACA-LIN: 3:1 pilot ratio, external drain, T-11A cavity
- CAGA-LIN: 4.5:1 pilot ratio, external drain, T-11A cavity
- CACB-LIN: 3:1 pilot ratio, internal drain, T-11A cavity
