DF41X Integrated Low-Resistance Backflow Preventer is a device specifically designed to prevent backflow of pipeline media, suitable for scenarios such as municipal water supply, fire protection systems, and potable water pipelines, effectively avoiding water source contamination.

Core Functions

This device achieves bidirectional check valve functionality through a double-membrane structure. It automatically opens the drain valve when the pipeline pressure difference is less than 0.02 MPa, expelling backflow medium and introducing air to form a barrier, ensuring unidirectional water flow. Its operating principle is based on hydraulic control, using the pressure difference generated by local head loss to maintain the valve in a closed state. In case of abnormal conditions, the drain valve is opened through the联动 of the spring and diaphragm.

Applicable Scenarios

Municipal Water Supply System: Installed on the pipeline between the municipal network and the consumer's water meter to prevent backflow contamination.

Fire Protection System: Ensures emergency water supply safety for fire hydrants or fire outlet pipes.

Drinking Water Pipe: Prevents backflow of non-drinking water (such as fire water) into the drinking water supply system.

‌Industrial Applications: Suitable for pipeline systems with pressure fluctuations or potential water source contamination.‌

Structural Features

‌Dual-membrane design: Consists of two one-way check valves and a hydraulic-driven drain valve, featuring a compact structure.‌

Low Resistance Characteristic: Minimal resistance during normal water supply, without affecting flow efficiency.

Customized Support:法兰 connections and various materials (cast iron, cast steel, stainless steel) supported, adaptable to diverse operating conditions.

Installation Key Points

Pipe cleaning is required prior to installation to ensure no impurities affect the seal.

The valve body arrow direction must align with the water flow, and both ends require the installation of maintenance gate valves and filters.

The drain outlet of the drain valve must be elevated 300mm above the ground, accompanied by a drainage trench.