NFDC-LAN SUN Fully Adjustable Needle Valve Cartridge 350bar

Product Overview

The NFDC-LAN is a SUN Hydraulics fully adjustable needle valve cartridge designed for precise flow regulation. It features a sharp-edged orifice that is infinitely adjustable from fully closed to the maximum orifice diameter. As a non-compensated device, flow is proportional to the square root of the pressure differential across ports 1 and 2. The valve can serve as either a precision flow control or a reliable shut-off valve. Built to original SUN specifications with floating construction and exact cavity/flow-path compatibility (T-5A), it offers 100% drop-in interchangeability and is validated through simulated operating condition testing. The related NCEB-LCN version adds an integral reverse-flow check for unrestricted free flow from port 2 to 1 while retaining the same adjustable needle performance.

Technical Specifications 

• Model: NFDC-LAN (related model NCEB-LCN with reverse-flow check)
• Type: Fully adjustable needle valve
• Capacity: 12 gpm (0.25 inch / 6.4 mm orifice, approx. 45 L/min)
• Cavity: T-5A (Series 2)
• Maximum Operating Pressure: 5000 psi (350 bar)
• Control: L (Standard Screw Adjustment)
• Adjustment: Approximately 5 counterclockwise turns from fully closed to fully open
• Seal Material: N (Buna-N)
• Valve Hex Size: 1-1/8 in. (28.6 mm)
• Installation Torque: 45–50 lbf·ft (61–68 Nm)
• Adjustment Screw Internal Hex: 5/32 in. (4 mm)
• Locknut Hex Size: 9/16 in. (15 mm)
• Locknut Torque: 80–90 lbf·in (9–10 Nm)
• Weight: Approx. 0.60 lb (0.30 kg)
• Seal Kits: Buna 990203007; Viton 990203006 and others available
• Flow Path: Bi-directional (preferred direction port 1 to 2 for interchangeability)

Key Technical Advantages

• Sharp-edged orifice design minimizes flow variations caused by viscosity changes, delivering consistent performance across varying temperatures and fluid conditions.
• Balanced adjustment mechanism allows easy, low-effort regulation even under high system pressure, reducing the risk of binding or damage during setting.
• SUN floating construction compensates for cavity tolerances and installation torque variations, minimizing internal binding and ensuring long-term reliability and interchangeability.
• True zero leakage when fully closed enables dual use as a precision metering valve or positive shut-off valve.
• Precision machining, robust materials, and 100% simulated-duty testing guarantee stable performance and extended service life at 350 bar under repeated adjustment cycles.

Application Areas

Ideal for precise flow metering or shut-off in hydraulic systems, including injection molding and die-casting machine speed control, metal-forming equipment fine speed adjustment, machine-tool feed and clamping circuits, construction machinery auxiliary flow control, test-bench flow setting, packaging and automation equipment speed regulation, and any industrial application requiring infinitely variable flow from closed to maximum orifice.

Expert Maintenance Tips

Ensure the T-5A cavity is clean and free of burrs before installation. Tighten to the specified 45–50 lbf·ft torque only. When adjusting, loosen the locknut, turn the screw counterclockwise to increase opening (approximately 5 turns full range), then re-torque the locknut. Preferred flow direction is port 1 to 2 for maximum interchangeability with other flow-control cartridges. Maintain fluid cleanliness at ISO 4406 18/15 or better and inspect seals periodically. Verify zero leakage in the closed position. Use only recommended seal kits for service. After initial installation, confirm full adjustment range and flow characteristics. Store in a clean, dry environment.