Yongda
Yongda
Explore our high-grade brass valve assemblies, PEX fittings, and heavy-duty connector networks engineered for commercial and domestic infrastructures.
A whitepaper breakdown of hydrodynamics, material integrity, and operational safety in high-stress fluid distribution environments.
Check valves, also known as non-return valves (NRVs), represent the frontline defense in fluid systems against reverse flow, water hammer, and pump back-pressure. Whether configured in simple residential hot water lines or critical industrial cooling towers, these valves allow fluid to flow in a single direction while mechanically shutting off whenever upstream flow stalls or reverses. Achieving leakage-free sealing and precise cracking pressures demands high-performance metallurgical compositions and rigorous design standards.
A primary factor when buying a flow check valve is the "cracking pressure"—the minimum upstream pressure at which the valve begins to open and allow flow. In typical spring-loaded vertical and horizontal check valves, this value is calibrated via precise spring rates. A low cracking pressure minimizes hydraulic resistance, while a high spring force prevents reverse contamination before it can initiate. System designers must calculate the flow coefficient ($K_v$ or $C_v$) to balance flow rates with potential pressure drop limits across the piping layout.
While cast iron and stainless steel have their niches, brass remains the material of choice for medium-to-high pressure commercial plumbing, heating systems, and water distribution networks due to its exceptional ductility, corrosion resistance, and low friction coefficient. Lead-free alloys are increasingly mandated for potable water systems in North America and Western Europe, leading to the development of specialized Dezincification Resistant (DZR) brass. These alloys prevent the selective leaching of zinc when exposed to aggressive soft water, assuring the structural integrity of the valve over decadal life cycles.
| Valve Type | Common Materials | Cracking Pressure Range | Primary Industrial Application | Standards Compliance |
|---|---|---|---|---|
| Spring-Loaded Vertical Check | CW617N, DZR Brass, SS304 | 0.02 to 0.05 Bar | Domestic Plumbing, Underfloor Heating Manifolds | EN 12165, CE |
| Y-Strainer Check Combo | Nickel-Plated Brass, Bronze | 0.05 to 0.10 Bar | Boiler Inlets, HVAC Heat Exchangers | ISO 9001:2015, WRAS |
| Foot Valve with Strainer | Forged Brass, Stainless Screen | Gravity Activated | Suction Line Pump Protection | SGS Tested, RoHS |
| Piston-Style Inline Check | Lead-Free Brass, EPDM O-Rings | 0.10 to 0.20 Bar | Pneumatic Lines, Closed Loop Solar Thermal | NSF/ANSI 61, CSA |
With decades of experience, we provide high-grade brass valves, fittings, and HVAC system solutions to global markets.
Yuhuan Yongda Fluid Control Co., Ltd. (formerly Yuhuan Yongda Plumbing Co., Ltd.) was founded in 1996 and is strategically located in Yuhuan, Zhejiang—widely recognized as the "China Valve Capital". As a premier fluid control specialist, the company excels in product design, raw material sourcing, forging, machining, assembly, and quality assurance.
Our comprehensive portfolio is structured across three core segments: high-grade brass valves, connection fittings, and specialized HVAC components. Our products are engineered for middle and high-grade segments, highlighting durability, lead-free compliance, and eco-friendly features preferred by demanding engineering firms in North America and Europe.
Our newly established brand, Cokaren, represents our commitment to refined aesthetics and uncompromising performance. Rooted in our brand promise, "Keep flowing, keep warming", Cokaren delivers home comfort and municipal engineering reliability with every connection.
Struggle, Enterprising, Pragmatic, and Innovative.
Fine work, zero leakage, and absolute mechanical safety.
Operating a sprawling manufacturing base with an actual usable area reaching 80,000 square meters, we maintain strict control over our metal casting and forging lines. With over 600 sets of advanced testing machinery—including 80 specialized mechanical toolings—we run high-pressure gas testing and chemical analyzer assessments on every batch of brass.
Yongda has achieved full verification for major management systems, confirming our position as a reliable industrial partner:
Every batch of our brass valves, balance valves, and manifolds undergo extreme pressure cycling and thermal shock validation tests. Our commitment to quality prevents water systems from scaling, cracking, or prematurely wearing down under tough conditions.
Ensuring compliance, high energy-efficiency, and robust physical performance across global municipal and heating markets.
In the United States and Canada, modern code compliance dictates strict lead-free brass formulations for potable water lines (Safe Drinking Water Act guidelines). Additionally, hydronic underfloor heating loops rely heavily on zone valves and air vent systems to balance dynamic pressure waves. Check valves installed in these setups must withstand high-temperature water-glycol mixtures without seal degradation. For local plumbers, we offer OEM support for NPT threads, sweat-to-solder joints, and PEX compression ends.
European heating networks focus on reducing energy consumption through precise balancing. Check valves with integrated strainers play a vital role here, protecting pumps from rust and scale while preventing reverse flow. Our CW617N brass components conform to strict European EN standards (such as EN 12165), offering direct drop-in integration with heat meters, boiler connections, and multi-port floor manifolds.
As building systems become more connected, fluid networks are transitioning to smart infrastructures. The development of our next-generation balancing and non-return configurations focuses on integration with low-pressure drop architectures. By using advanced flow simulations, we are reshaping our valve paths to minimize internal turbulence, which lowers pump energy demands and supports global carbon reduction efforts.
Located in Yuhuan, the heart of China’s brass industry. We maintain continuous production through direct material access and optimized in-house forging.
Equipped with specialized tooling machinery, we prototype, forge, and machine custom designs within weeks, meeting tight project deadlines.
Exporting to more than 20 countries. Our logistics network ensures smooth customs processing and timely deliveries globally.
Operational photos showing our advanced machinery and specialized plant setups in Yuhuan, China.
Clear answers to technical and purchasing questions about check valve systems, material selections, and dynamic performance.
The unit price is driven by three main factors: metallurgical alloy purity (such as CW617N brass vs lead-free brass), the precision of machining (tight tolerances on internal guides), and certified testing requirements (such as 100% pneumatic pressure testing). High-volume runs at our Yuhuan plant lower unit costs by optimizing tool setups and raw material utilization.
Spring-loaded check valves close quickly before reverse fluid flow can occur. This rapid response prevents hydraulic pressure shocks, commonly known as water hammer. The brass body is also highly resistant to the thermal cycles typical in heating networks, ensuring reliable operation over a long service life.
For drinking water applications, ensure the manufacturer complies with ISO 9001 quality systems and offers certified lead-free brass. We verify compliance through international test bodies, providing complete material reports with every bulk shipment.
EPDM seals work well in hot and cold water networks, maintaining flexibility up to 120°C. For systems involving oils or fuels, NBR seals provide superior chemical resistance, while Viton is preferred for high-temperature and harsh fluid environments.
Yuhuan is the brass manufacturing capital of China, grouping raw material supplies, specialized hot forging centers, and logistics providers close together. This local setup cuts transit times, streamlines material handling, and lowers production overhead.
Yes. We machine threads to BS21 (BSP), ISO 228-1, or ANSI/ASME B1.20.1 (NPT) standards, ensuring direct compatibility with European and North American piping connections.
Explore our temperature control components, threaded adapters, and manifold accessories for high-performance buildings.
