Yongda
Yongda
Explore our core range of high-precision brass valves, manifolds, and fluid control modules built to withstand extreme dynamic stress.
In the arena of modern fluid dynamics, managing backflow prevention is critical for protecting equipment life and process safety. The diaphragm check valve serves as a reliable inline safety component, allowing unidirectional fluid travel and instantly closing off backflow using elastomeric or spring-assisted sealing mechanisms.
Unlike standard metal-seated check valves, diaphragm check valves operate effectively under extremely low cracking pressures. They provide complete, drip-tight sealing even when differential pressure is minimal. This design is highly valuable in high-sensitivity environments, including water purification systems, HVAC energy loops, zone manifold distributions, and delicate chemical processing lines.
As global clean water standards rise and the demand for energy-efficient heating infrastructures grows, selecting a supplier in China requires looking beyond product volume. It demands verifying advanced manufacturing standards, strict adherence to global certifications (such as ISO 9001 and ISO 14001), and a clear understanding of metallurgy and elastomer performance.
Established in 1996 and situated in Yuhuan, Zhejiang—widely recognized as the "Valve Capital of China"—Yuhuan Yongda Fluid Control Co., Ltd. (formerly Yuhuan Yongda Plumbing Co., Ltd.) has developed into an industry-leading manufacturer of plumbing valves, brass fittings, and HVAC system components.
We focus on design, engineering development, automated manufacturing, and global distribution. By prioritizing environmental sustainability and precision design, our product lines satisfy the strict plumbing and industrial requirements of markets across North America, Europe, and Asia.
Through our dedicated brand Cokaren, we commit to the promise: "Keep flowing, keep warming". This promise guides our engineering work, ensuring that every valve, fitting, and manifold delivers reliable performance to keep water systems running efficiently and safely.
Modern fluid infrastructure requires check valves to handle higher dynamic pressures, minimize water hammer, and maintain strict material purity.
Transitioning to low-lead and lead-free brass (e.g., CW617N, DZR, C37700). This step eliminates heavy metal leaching into drinking water networks, meeting NSF/ANSI 61 and new EU potable water regulations.
Formulating diaphragm polymers using advanced EPDM, FKM (Viton), and NBR compounds. These materials offer improved chemical resistance, stable elasticity from -20°C to 150°C, and excellent fatigue life across millions of cycles.
Using CFD simulations to design flow pathways. This reduces flow turbulence and pressure drop, helping check valves operate at lower cracking pressures while retaining high flow rates.
Embedding micro-pressure and position sensors into check valve assemblies. This enables real-time monitoring of flow rates, backpressure levels, and seal degradation within automated industrial networks.
The modernization of manufacturing in China has reshaped the valve export industry. At Yuhuan Yongda, we run a modern factory with over 45,000 square meters of floor space and an actual usable area of 80,000 square meters. The plant integrates lean manufacturing methods with modern quality control.
Our facility utilizes over 600 sets of production and testing equipment, including 80+ specialized machine tools. This precision machinery ensures uniform valve threads, precise seat tolerances, and high finish quality, keeping reject rates low.
We apply pressure tests to every assembly. Every diaphragm check valve undergoes hydrostatic seal testing and pneumatic seat tests to verify leak-free performance.
By managing raw copper smelting, extrusion, forging, machining, and final testing locally, we control lead content and keep delivery schedules predictable.
Modern fluid systems rely on check valves to act as safety barriers in complex installations. Rather than looking at check valves as isolated components, we design them to integrate cleanly with larger HVAC, plumbing, and distribution systems.
In underfloor heating systems and mixing shunts, diaphragm check valves prevent backflow and unwanted mixing between hot supply water and cold return water. This ensures stable temperature zones and helps smart thermostats regulate home comfort efficiently.
As the first line of defense in home water networks, check valves prevent cross-contamination by stopping non-potable water from siphoning back into main supply lines. Our low-leakage check valves protect residential systems from pressure spikes.
High-efficiency boilers require steady flow direction. Installing diaphragm check valves prevents hot water back-siphoning into cold water supply lines, protecting boilers and reducing heating losses.
We assist global procurement managers, mechanical engineers, and wholesale distributors by providing custom engineering, localized compliance documentation, and rapid prototyping services.
We manufacture valves to match localized specifications globally, including NPT, BSPT, and BSPP thread profiles, alongside compression and press-fit styles. This ensures straightforward installation on site.
We supply material certification sheets detailing copper, zinc, and trace element percentages. This guarantees compliance with lead regulations and proves our products meet strict industrial standards.
For custom projects, we adjust spring tension and elastomer thickness to deliver specific cracking pressures, catering to gravity-fed, low-head, and high-pressure industrial systems.
Our manufacturing facilities comply with international regulations to ensure consistent quality and reliable service.
Quality Management System Certification
Environmental Protection Standards
Occupational Health & Safety Compliance
Our water valves and manifold assemblies control, balance, and distribute heating media across residential and industrial networks.
First line of defense in home plumbing, filtering out 98% of particulate impurities.
Discharges accumulated air from high-temperature loops to optimize heating performance.
Get answers to technical questions about fluid sealing, materials, cracking pressures, and procurement.
Browse our selection of brass fittings, multilayer composite pipes, and thermostats for modern installations.
