The KOFLOC CR-400B is a high-precision mechanical constant flow valve from the renowned CR Series manufactured by KOFLOC (Kojima Instruments Inc., Japan). It is specifically engineered to resolve flow instability problems caused by continuous supply pressure (primary pressure) or load pressure (secondary pressure) fluctuations across gas delivery channels.

The instrument integrates an ultra-sensitive diaphragm differential pressure compensation mechanism with an internal precision needle valve. When system pressure fluctuates, the internal diaphragm automatically modulates valve opening to balance differential pressure, maintaining instantaneous flow rates strictly at the preset value. Fully self-operated without electrical power requirements, the CR-400B offers intrinsic safety and outstanding reliability for semiconductor cleanrooms, optical purge setups, gas chromatography analysis, and industrial inert blanketing.

• Manufacturer: KOFLOC (Kojima Instruments Inc.)
• Brand Origin: Japan
• Full Model Designation: CR-400B
• Product Classification: Precision Constant Flow Valve / Differential Pressure Flow Regulator
• Regulation Principle: Automatic compensation for secondary/primary pressure fluctuations to guarantee constant output flow
• Applicable Fluids: Clean Compressed Air, Nitrogen (N2), Argon (Ar), Helium (He), CO2, and non-corrosive industrial gases
• Controllable Flow Range: Selectable flow spans from micro ranges (0.5 – 5 L/min) up to standard ranges (10 – 30 L/min)
• Maximum Primary Supply Pressure: 0.7 MPa (approx. 7 bar / 100 psi)
• Proof Pressure: 1.0 MPa (10 bar)
• Minimum Required Differential Pressure: 0.05 MPa – 0.1 MPa (Required across IN/OUT for stable governing)
• Flow Control Stability: Flow variation ≤ ±1.0% F.S. against pressure changes
• Flow Adjustment Mechanism: Built-in precision micro needle valve with multi-turn fine adjustment knob
• Process Connections: Rc 1/4" female threaded ports (Optional 1/4" NPT industrial standard)
• Flow Direction: Unidirectional flow indicated by body flow arrow (IN → OUT)
• Body Material: Stainless Steel (SUS303/SUS304/SUS316) or high-grade nickel-plated brass
• Diaphragm Material: High-elasticity FKM / Viton or synthetic NBR elastomer
• Sealing & O-Ring Material: Chemical- and heat-resistant FKM (Viton)
• Operating Temperature Range: 5°C to 60°C (Fluid and Ambient)
• Installation Style: Inline piping mount or instrument panel mount
• Typical Applications: Carrier gas flow stabilization in gas chromatography, inert purging for vacuum furnaces, heat treatment atmosphere control, leak rate test benches, and analytical laboratory manifolds