Yongda
Yongda
Engineered to prevent backflow and regulate pressure dynamics in critical municipal, commercial, and HVAC fluid environments.
Founded in 1996 as Yuhuan Yongda Plumbing Co., Ltd. and later renamed to Yuhuan Yongda Fluid Control Co., Ltd., we have anchored ourselves in the "China Valve Capital" – Yuhuan, Zhejiang. For over two decades, our operation has been laser-focused on design, development, high-tier production, and international logistics of top-tier plumbing systems, HVAC equipment, and premium brass valves.
Our strategic operations target medium-to-high-grade market requirements. By utilizing ecological DZR, low-lead, and lead-free brass formulations, we provide critical solutions that harmonize structural efficiency with strict ecological guidelines, earning sustained procurement from key distributors in North America, Europe, and neighboring highly-regulated jurisdictions.
Under our premium brand Cokaren, with the operational commitment of "keep flowing, keep warming", we strive to bring unmatched temperature stability, system safety, and functional durability into homes and commercial facilities worldwide.
A comprehensive white paper on engineering standards, fluid physics, and quality metrics governing automatic air release & check systems.
In closed-loop hydraulic and HVAC networks, entrained air is an active threat to system integrity. Gas enters hydraulic loops via municipal supply refills, fluid temperature spikes (which lower gas solubility according to Henry's Law), and micro-leaks at negative-pressure junctions. Free air bubbles block optimal fluid flow, leading to thermal lockouts, severe cavitation within circulating pumps, and rapid oxidation of interior pipe components.
An automatic vent check valve resolves these issues through a mechanical float-vent architecture. As gas separates from the liquid stream, it pools inside the valve chamber. The accumulation drives down the internal liquid level, forcing the float downward. This float transition opens the exhaust vent orifice to release the trapped gas. Once the gas is released, the fluid level rises again, lifting the float and sealing the vent to prevent liquid escape. The integrated check-valve component prevents external atmospheric air from back-siphoning into the system during periods of thermal contraction or system drain-down.
Our valves are constructed from specialized alloys to prevent zinc loss in soft water environments, protecting structural integrity.
We utilize high-temperature elastomer compounds rated for continuous operational heat cycles up to 120°C without elastomer degradation.
Every single unit undergoes pressurized pneumatic validation to guarantee zero leakage prior to custom packaging and distribution.
| Parameters | Standard Brass Air Vent | Industrial Spring Vent Check | Cokaren HVAC Integrated Vent System |
|---|---|---|---|
| Working Pressure Limits | Up to 6 Bar | Up to 10 Bar | Up to 16 Bar (PN16 rated) |
| Sealing Compound | Standard Nitrile / NBR | High-Temp EPDM | Reinforced Viton / Special EPDM Mix |
| Back-Siphon Mitigation | None (Standard Exhaust) | Basic Mechanical Poppet | Dual-Function Backflow Inhibitor Cartridge |
| Primary Industrial Sectors | Domestic Radiator lines | District Heating & Process Cooling | Multi-Zone Underfloor manifolds & Heat Pumps |
As global energy efficiency directives become more strict, manufacturers must adjust their material strategies. At Yuhuan Yongda, our metallurgical roadmap emphasizes lead-free brass formulations (e.g., CW617N, CW614N, and Lead-Free Alloys compliant with California AB1953) to address growing clean-water mandates. High-precision hot forge machines are used to minimize micro-porosity defects in valve bodies. The valve float mechanism is engineered with lightweight, heat-stable polymers (such as Polypropylene or Polysulfone) to ensure reliable buoyancy and long-term mechanical responsiveness.
We believe that a high-performing product starts with a rigorous production culture. Guided by our corporate core values of being Struggle, Enterprising, Pragmatic, and Innovative and our quality target of "Fine work, no leakage", we maintain a complete management control workflow.
Our quality assurance systems are verified by international testing bodies, conforming to the following frameworks:
We deploy special-purpose testing stations, including high-pressure hydraulic cycles, pneumatic integrity chambers, and chemical composition analyzers, to ensure that all shipments meet performance specifications.
Our HVAC and fluid control product line works together to ensure stable pressure, temperature control, and air-free distribution loops.
The first line of defense in domestic water sanitation, can filter 98% of impurities in the pipeline.
Technical Parameters
Used to control the inflow and outflow of cold water and hot water in the boiler, with Spherical spool.
Technical Parameters
Used to discharge excess air in the air source water heater to ensure stable operation of the equipment.
Technical Parameters
Used to mix cold and hot water in pipes, stabilizing temperature, protect pipeline.
Technical Parameters
Combine all the equipment to adjust the room temperature.
Technical Parameters
Used to filter and discharge impurities in the pipeline, control the switch of the back-end manifold, measure temperature and water pressure.
Technical Parameters
Distribute water flow to various rooms. Combine all the equipment to adjust the room temperature.
Technical ParametersIndustrial Piping Layout Reference Diagram:
Premium options for municipal supply networks, commercial plumbing systems, and underfloor thermal distribution loops.
One of the outstanding features of this valve is its integrated filtration screen, capturing micro-particles.
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Allows manual adjustments for balanced thermal distribution in heating circuits.
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High-accuracy thermostatic mixing element balancing back-end manifold loops.
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Distributes flow rates smoothly to target heating or cooling zones.
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Durable outdoor design resistant to freeze-thaw cycles and stress corrosion cracking.
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Ensures straight-through, low-resistance fluid flow for system isolation.
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Precision-threaded coupling extensions for municipal utility configurations.
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Hose tail connections designed for standard industrial hoses.
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High-integrity diverter core with adjustable pressure control settings.
Nickel-plated anti-corrosion finish for outdoor industrial water taps.
Integrated threaded coupling joint for quick system installations.
Heavy-duty construction rated for residential and municipal main loops.
Overpressure mitigation device for hot water storage cylinders.
Key-locked mechanism for public water systems to prevent unauthorized access.
Constructed with dezincification-resistant brass for long operational lifetimes.
Combination backflow preventer and inline filter screen for clean flow.
Removes solid particulates from flow loops to protect pump seals.
Engineered for pump suction lines, preventing dry start conditions.
Inline backflow preventer designed for simple plumbing systems.
Combines mechanical mixing with circulation control for multi-zone systems.
Dynamic manifold temperature control system designed for domestic heating networks.
Maintains target temperatures across underfloor hydronic circuits.
Relieves excess dynamic pressure while continuously purging air bubbles.
Simple screw-operated venting plug for manifold end connections.
Adjustable venting rate limits for complex industrial fluid loops.
High-capacity air venting components designed for heat source units.
Dual-function exhaust and drain fitting designed for manifold end zones.
High-reliability mechanical joints for PE pipe networks.
Precisely machined ISO-threaded connectors for industrial plumbing.
Expert insights on streamlining supply chains, addressing material compliance, and selecting plumbing components.
Industrial piping designers face strict regulatory frameworks globally. In the United States, the Safe Drinking Water Act (SDWA) limits the lead content on wetted surfaces to a maximum of 0.25%. In Europe, REACH regulations and the UBA positive list control which copper alloys can be used for drinking water systems. These requirements make it essential to verify the metallurgical composition of valves. Yuhuan Yongda works closely with international testing labs to supply certified dezincification-resistant (DZR) and lead-free brass products, helping buyers comply with local regulations.
A vent check valve is most effective when integrated into a well-designed hydronic circuit. As shown in our product catalog, using automated components like the NC Thermal Actuator alongside manual balancing elements like Mixing Shunts and Manifolds creates a balanced system. The mixing shunt stabilizes inlet temperatures, protecting PEX lines from thermal stress, while the automatic air vent continuously expels micro-bubbles that could disrupt heat transfer. This coordinated system maintains stable pressure differentials and reduces energy consumption in commercial HVAC projects.
At Yuhuan Yongda, we combine automated hot forging press lines with high-speed CNC machining centers to ensure tight dimensional tolerances across production batches. Standardized thread forms (BSP, BSPT, NPT) are precision-cut using thread gauges to prevent leaks during installation. Additionally, our automated assembly units perform continuous air-under-water tests to verify that sealing gaskets are seated properly and check-valve spring rates meet specifications.
Detailed explanations to common engineering and sourcing questions from fluid control professionals.
Complete your project sourcing with our range of temperature control valves, smart controls, and reliable connection adapters.
