Flow Control Valve

1. Product Overview

The 400X Flow Control Valve, also called constant flow regulating valve, is a pilot-diaphragm type hydraulic control valve, matching your series of ductile iron water valves (500X relief valve / 600X solenoid valve). The valve body is cast from QT450 nodular cast iron with blue epoxy anti-corrosion coating, standard double flange connection, PN10/PN16 pressure rating.

It operates purely by pipeline medium pressure without external power supply, designed to lock downstream flow at a preset fixed value regardless of upstream pressure fluctuation, widely used in municipal water distribution, building HVAC, farm irrigation and industrial circulating water systems.

2. Working Principle

Equipped with a high-precision flow sensing pilot and differential pressure detection structure, the valve monitors real-time flow difference across the built-in orifice plate.

If upstream pressure rises and flow exceeds the set value: The pilot drives the main valve disc to narrow the opening, throttling excess water to stabilize flow.

If upstream pressure drops and flow is insufficient: The main valve automatically opens wider to maintain the target flow rate.

The top red manual needle valve adjusts opening/closing speed to suppress destructive water hammer during flow regulation.

3. Core Features

Precise Constant Flow Locking

Maintains fixed downstream flow steadily even with dramatic upstream pressure changes, avoids pipeline overload and uneven water distribution.

Self-Powered Hydraulic Operation

No electricity, air compressor or actuator required; fully driven by water pressure, low failure rate and energy-saving.

Adjustable Anti-Water Hammer Design

Built-in flow needle valve for slow open/close, eliminates pipeline vibration, pressure surge and pipe burst risk.

Durable Corrosion-Resistant Build

QT450 ductile iron body, brass control tubing, EPDM/NBR soft sealing for zero leakage; epoxy coating resists rust in underground water pipelines.

Easy Installation & Maintenance

Integrated split main valve structure; pilot accessories can be replaced without removing the valve from the pipe network.

4. Main Application Scenarios

Municipal water supply branch pipe flow balancing & limit

High-rise building domestic water & HVAC circulation flow regulation

Farm irrigation main pipeline fixed flow control

Factory cooling water, wastewater recycling flow management

Reservoir water distribution and pump outlet flow protection

5. Standard Technical Parameters (DN100 PN16 Reference)

Model: 400X-16Q

Nominal Diameter: DN50 ~ DN600

Nominal Pressure: PN10, PN16

Body Material: QT450 Nodular Cast Iron

Sealing Material: EPDM Rubber

Connection Standard: GB, ANSI, DIN Flange

Working Medium: Clean tap water, raw water, fire water

Working Temperature: 0℃ ~ 80℃

Flow Adjustment Range: Customizable per client pipeline demand