Low resistance backflow preventer

Backflow preventer is mainly used to prevent the medium in the pipeline from backflow due to pressure inversion, applicable to water, air and non-corrosive liquids, widely used in municipal water supply, building water supply and drainage, fire-fighting and industrial circulation system. Working temperature is generally 0 ℃ to 80 ℃, special materials can withstand higher temperatures. It is suitable for normal pressure to low and medium pressure working conditions. The main function is to realize double protection through the internal non-return and pressure relief structure to prevent backflow of contaminated media. Commonly used materials include copper alloy, stainless steel and ductile iron, compact structure, easy maintenance, to protect the system water quality safety and operational stability.

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products

Low resistance backflow preventer

Model: DH43X

Subtitle：Anti-Reflux Valve

The Low Resistance Backflow Preventer is a highly efficient device designed to prevent backflow and protect water systems from contamination while minimizing pressure drop. With optimized flow paths and advanced sealing technology, this backflow preventer ensures reliable operation and energy savings in potable water, fire protection and industrial systems.

Classification:backflow preventer

Working conditions:construction work, waterwork, water treatment plant

Product Overview

Constructed of stainless steel, bronze or ductile iron, the valve is durable and corrosion-resistant for applications requiring high flow rates and low maintenance. Its low resistance design reduces energy consumption, making it ideal for systems where pressure loss is critical.

Applicable working conditions

Drinking water systems: protect municipal water supply networks from backflow contamination.

Industrial processes: protection of process water systems in the chemical, pharmaceutical and food industries.

Irrigation: prevent fertilizers and chemicals from entering the water supply.

Product Characteristics

Low resistance design: optimized flow path ensures minimum pressure drop (flow coefficient: Cv ≥ 1.5 for DN50). Ideal for high-flow systems such as water supply and fire fighting networks.

Reliable backflow protection: double check valves with intermediate relief chamber ensure zero backflow. Meets ASSE 1013, CSA B64.4 and EN 1717 standards.

Durable construction: Valve body material: stainless steel (316L), bronze (C83600), or ductile iron (EN-GJS-400-18). Internal components: Stainless steel components for corrosion resistance and long service life.

Low Maintenance: Self-cleaning design and easily accessible inspection ports simplify maintenance. Replaceable seals and springs reduce downtime and repair costs.

Compliance: Meets international standards such as ASSE 1013, CSA B64.4 and EN 1717.

Product Advantages

Energy saving: low resistance to flow minimizes pump energy consumption.

Water safety: Double check valves and pressure relief chamber ensure zero backflow contamination.

Space efficiency: Compact design reduces installation space and simplifies piping layouts.

Easy maintenance: self-cleaning design and replaceable components reduce downtime.

Comparison with standard check valves

specificities	Low resistance backflow preventer	Standard Backflow Preventer
flow resistance	Low (Cv ≥1.5 at DN50)	High (Cv ≤1.0 for DN50)
energy efficiency	High (reduces pump workload)	Lower (higher pressure loss)
appliance	High-flow systems (water supply, fire fighting)	Universal water systems
cost-effectiveness	Higher upfront costs, lower life cycle costs	Lower upfront costs

Medium of use

Water/hot water, Sewage/wastewater

working condition

construction work, waterwork, water treatment plant

summarize

The Low Resistance Backflow Preventer is a high-performance solution that prevents backflow and ensures water safety in potable water, fire protection and industrial systems. Its low resistance design, durable construction and compliance with international standards make it ideal for applications where energy efficiency and reliable performance are important. The backflow preventer combines advanced technology with user-friendly operation to ensure long-term system protection and water quality.

Product Parameters

Nominal diameter	DN50 to DN300 ( 2" to 12")
Nominal pressure	PN16 to PN25 (EN 1092) or Class 150 to Class 300 (ASME B16.34)
temperature range	-10°C to 120°C (EPDM seals) / -20°C to 80°C (NBR seals)
Valve Material	Stainless steel (316L), ductile iron (EN-GJS-400-18), WCB
sealing material	EPDM, NBR or PTFE for zero leakage
connection method	Flanges (EN 1092, ASME B16.5)
leakage rate	Class VI (ISO 5208)