OverviewThe eccentric hemisphere valve (also known as half-ball valve) is a high-performance quarter-turn industrial valve, designed with a double-eccentric hemispherical core and metal-to-metal or soft seal. It provides bubble-tight shutoff, low torque operation, and excellent resistance to abrasion, scaling, and harsh media. Widely used for on/off and throttling control in pipelines handling water, sewage, slurry, steam, gas, oil, and corrosive fluids.
Key Advantages
Zero-Friction Opening & Closing, Long Service LifeDouble-eccentric design enables the hemisphere to detach from the seat first then contact only at the final closing stage, eliminating seal face friction during operation. Service life is 3–5 times longer than conventional ball valves, gate valves, or butterfly valves.
Bubble-Tight Bi-Directional SealingEccentric wedge principle plus elastic seat design delivers bi-directional zero leakage (bubble-tight). Ideal for toxic, flammable, or valuable media such as natural gas, chemicals, and hazardous wastewater.
Low Operating Torque & Energy SavingRequires only 1/3 the torque of traditional valves. Works with smaller actuators (manual, gear, electric, pneumatic), reducing equipment cost and power consumption.
Full Bore Flow, Minimal Pressure LossStraight-through full bore design ensures zero head loss when fully open, no media deposition in the cavity, and smooth flow even for high velocity or large solid particle media.
Self-Cleaning & Anti-ScalingThe hemispherical core has a shearing edge that scrapes off scale, dirt, or fibers during closing. Prevents jamming and keeps the seal face clean, perfect for slurry, pulp, and scaling media.
Wide Temperature & Pressure Rangemetal-seated type withstands -29°C to 560°C, pressure from PN16 to PN250 (Class 150–1500). Available in carbon steel, stainless steel (304/316), alloy steel, and special alloys for corrosion/abrasion resistance.
Applications
Water & Wastewater Treatment: Municipal water supply, sewage, sludge, desalination.
Power Plant: Fly ash, slag removal, FGD (flue gas desulfurization), steam lines.
Standards: API 6D, ISO 9001, CE, fire-safe API 607
Technical Parameters
The following are the standard technical parameters of our eccentric hemisphere valve, which can be customized according to your specific working conditions and design requirements.
Item
Specification
Valve Type
Eccentric Hemisphere Valve (Half Ball Valve)
Nominal Size
DN50 - DN1400 (2” - 56”)
Nominal Pressure
PN16/25/40/64/100/160/250 (Class 150 - 1500)
Working Temperature
-29°C ~ +425°C (Metal seal up to 560°C)
Body Material
WCB, A351 CF8/CF8M, Ductile Iron (DI), Alloy Steel
Customization is available for special pressure, temperature, material and connection requirements. Please contact us for detailed customized solutions.
Eccentric Hemisphere Valve - Manufacturing Process Display
We adhere to strict manufacturing standards and sophisticated production processes to ensure each eccentric hemisphere valve has excellent performance, stable quality and long service life. The following is the detailed display of our core manufacturing process, from raw material selection to finished product delivery, every link is strictly controlled.
1. Raw Material Selection & Inspection
High-quality raw materials are the foundation of valve quality. We select WCB carbon steel, CF8/CF8M stainless steel, ductile iron and special alloy materials that meet API 6D and ISO standards. Each batch of raw materials will go through strict chemical composition testing, mechanical performance testing and flaw detection to ensure no impurities, cracks or defects, laying a solid foundation for subsequent production.
2. Precision Casting / Forging
According to the valve size and working conditions, we adopt precision casting or forging process:
Precision casting: Suitable for medium and large size valves (DN100-DN1400), with high dimensional accuracy, smooth surface and complete internal structure, avoiding shrinkage, porosity and other defects.
Forging: Suitable for high-pressure, high-temperature valves (PN100-PN250), the forging process enhances the density and mechanical strength of the material, making the valve more resistant to pressure, wear and impact.
3. CNC Machining & Precision Grinding
The valve body, hemisphere core, valve seat and stem are processed by high-precision CNC machine tools, with machining accuracy up to ±0.01mm. Key parts such as the hemisphere sealing surface and valve seat are subjected to precision grinding and polishing treatment, ensuring the flatness and smoothness of the sealing surface. The double-eccentric structure is accurately positioned by professional fixtures, ensuring the concentricity and eccentricity error meet the design requirements, laying the foundation for zero leakage and low torque operation.
4. Sealing Surface Treatment
The sealing performance is the core of the hemisphere valve. We adopt two advanced sealing surface treatment processes:
Metal-to-metal seal: Stellite hardfacing is applied to the hemisphere and valve seat sealing surface, with hardness up to HRC60-65, which is wear-resistant, high-temperature resistant and corrosion-resistant, suitable for harsh working conditions such as high pressure, high temperature and abrasive media.
Soft seal: High-quality PTFE, EPDM or NBR materials are used for the valve seat, which has excellent sealing performance and can achieve bubble-tight zero leakage, suitable for medium and low pressure, non-abrasive media.
5. Assembly & Debugging
The assembly process is carried out in a clean workshop to avoid dust and impurities affecting the valve performance. Professional technicians assemble the valve body, hemisphere, stem, seat, actuator and other parts in strict accordance with the assembly process. After assembly, each valve is subjected to manual or automatic debugging, testing the opening and closing flexibility, torque size and sealing performance, ensuring that the valve operates smoothly without jamming, and the sealing meets the standard.
6. Strict Quality Inspection
Before leaving the factory, every hemisphere valve must go through a series of strict quality inspections, including:
Pressure test: Hydrostatic test and air tightness test are carried out to ensure no leakage under rated pressure.
Flaw detection: Ultrasonic flaw detection, radiographic flaw detection and magnetic particle flaw detection are used to check the internal and external defects of the valve.
Dimensional inspection: Recheck the key dimensions such as flange size, eccentricity and sealing surface flatness to ensure consistency with the design drawing.
Operation test: Test the opening and closing torque, stroke accuracy and actuator performance to ensure stable and reliable operation.
7. Packaging & Delivery
Qualified valves are packaged with anti-rust treatment, wrapped in waterproof and shockproof materials, and packed in wooden cases or cartons to avoid damage during transportation. Each valve is accompanied by a quality inspection report, material certificate and operation manual, ensuring that customers can use it with confidence.
Our manufacturing process adheres to the concept of "quality first, precision first", and has passed ISO 9001 quality management system certification. Each step of production is traceable, ensuring that every eccentric hemisphere valve delivered to customers meets the highest industry standards.
Application Project Cases
1. Thermal Power Plant
Our eccentric hemisphere valves are widely used in power plant ash slurry, slag water, flue gas desulfurization (FGD) and circulating water pipelines.With anti-abrasion, self-cleaning and bubble-tight sealing performance, they solve the problems of easy jamming, serious wear and leakage of traditional gate valves and butterfly valves in ash handling systems. Long service life and low maintenance cost.
2. Municipal Water & Sewage Treatment
Applied in municipal water supply, drainage pipeline, sewage sludge and raw water transmission project.The valve has full flow channel, no medium deposition, and bi-directional tight shutoff. It is suitable for long-distance water transfer and sewage treatment pipeline on-off and regulation.
3. Mining & Metallurgy
Used for mineral slurry, tailings pipeline, metallurgical ash water and high concentration slurry conveying.The hemisphere cutting edge can shear fiber and solid particles automatically, avoid blockage effectively. Metal hard seal design resists strong abrasion from ore slurry.
4. Oil & Gas / Refinery
Suitable for crude oil, natural gas, petroleum chemical medium and high temperature steam pipeline.Bi-directional zero leakage, fire-safe design, high pressure and high temperature resistance. Meet API 6D standard, safe for flammable and explosive media.
5. Chemical Industry
Applied in corrosive liquid, crystalline medium, high viscosity chemical fluid pipeline.Optional stainless steel and special alloy material. Anti-corrosion, anti-blocking, ideal for chemical process piping on-off control.
6. Pulp & Paper Industry
Perfect for pulp, fiber-containing medium and black liquor conveying pipeline.Self-cleaning structure prevents fiber from sticking to sealing surface, no stuck phenomenon during long-term operation.
点击图片查看原图
官方公众号
官方小程序
发表用户评论，可得5积分，积分可兑换“100元天猫卡”等实物好礼；更有机会成为“星级评价官”，享受专属权益，快来积极参与吧！
共0条