About SNT Butterfly Valves
SNT Machinery (Qingdao) Co., Ltd. stands as an industry leader in the realm of butterfly valves, bringing forth innovation with our uniquely designed, state-of-the-art processing techniques. Backed by over a decade of expertise, we are adept at engineering optimal solutions for even the most complex and demanding service conditions. Our butterfly valves boast unmatched market superiority, adhering to rigorous international benchmarks such as ASME B16.34-2009, GB/T12221-1989, and AP1607-2009. These exemplary products find their essential roles across diverse sectors including petroleum, chemical, light industry, pharmaceuticals, papermaking, metallurgy, and the rubber industry.
The AOC-3812 series triple offset butterfly valve by SNT delivers unparalleled performance with its bi-directional bubble-tight shut-off capability. Its unique geometric design guarantees unparalleled sealing effectiveness,
ensuring that the disc seal engages with the body seat only at the critical shut-off phase. This design eliminates any potential for rubbing or wear, thus providing exceptional torque management and extending the valve's lifespan.
The valve's resilient seal is ingeniously engineered with ample 'wedging' force, securing a reliable and steadfast closure to meet the most rigorous operational demands.
| Body Type |
AOC-3811 |
AOC-3812 |
| Body Size |
3''(80A)-24''(600A) |
3''(80A)-24''(1500A) |
| Body Rating |
ANSI Class 150-600 PN150-600 PN10-PN110 |
| Fluid Temperature |
-196~+500ºC |
-196~+500ºC |
| Connections |
Wafer Type/RF/Lug Type |
RF Flanged |
| Body Materials |
A216 WCB/A351 CF8/A351 CF8M,etc |
| Disc Materials |
A216 WCB/A351 CF8/A351 CF8M,etc |
| Disc Treatment |
Chrome Plated or Stellited |
| Range-ability |
60 degree Opening/25:1; 90 degree Opening/50:1 |
| Flow Characteristiscs |
Approximater Eq%(Inherent Characteristic) |
| Seal Ring Type |
FN |
FV |
CS |
KS |
FM |
M |
| Seal Raing Materials |
R.TFE |
R.TFE |
R.TFE |
Kel-F |
316+Graphite |
316SS |
| Back Ring Materials |
NBR |
VITON |
SUS316 |
SUS316 |
316SS |
316SS |
| Seat Leakage |
ANSI Class IV/V/VI |
ANSI Class VI |
| Actuator Combinations |
Pneumatic Cylinder Actuator/Electronic Actuator/Pneumatic Diaphragm Actuator |
Principle Of Operation
The SNT triple offset butterfly valve is engineered to deliver exceptional performance, featuring a bi-directional bubble tight shut-off that sets a new standard in sealing technology. Its innovative geometry is meticulously designed to ensure the disc seal engages with the body seat exclusively at the final shut-off position. This unique feature eliminates any possibility of rubbing or galling, providing a torque-generated resilient seal. The ingenious 'wedging' mechanism guarantees a uniform seal contact, ensuring unparalleled reliability and durability.
The Triple Offset Geometry
Offset 1 - Ingeniously designed, the shaft is positioned behind the seat axis. This strategic placement allows for a complete and uninterrupted sealing contact around the entire seat, ensuring maximum efficiency and performance.
Offset 2 - The shaft centerline is thoughtfully offset from both the pipe and the valve. This clever configuration provides interference-free opening and closing of the valve, enhancing operational smoothness and longevity.
Offset 3 - The seat cone axis is precisely offset from the shaft centerline. This eliminates friction during the critical processes of closing and opening, achieving a uniform compressive seal across the entire seat, enhancing durability and performance.
Innovative Design with Triple Eccentricity: Our design is meticulously crafted to withstand the harshest service conditions, including extreme temperatures and pressures, while ensuring minimal leakage. Experience the advantage of friction-free operation and low torque during opening and closing. Remarkably, increased fluid force enhances the sealing efficiency, setting a new standard in valve performance.
Robust Integral Structure: Featuring a unified seat ring and body, the sealing face is fortified with a high-strength alloy, ensuring exceptional reliability.
This guarantees the sealing face's durability and extends service life, achieving near-zero maintenance requirements.
Enhanced Safety with Stepped Seal: Designed to prevent blowouts, the robust integral stem, crafted from high-strength material, ensures superior pressure drop resilience and operational safety.
Innovative Stem and Disk Driving Method: By utilizing an offset round pin, we eliminate the necessity of drilling that compromises stem strength. This enhances the shearing strength and reliability of the round pin, ensuring unmatched security and durability.
Advanced Stem Sealing Design: Utilizing high-temperature resistant non-metallic materials, our stem sealing effectively prevents particle-laden fluids from entering the bearing, thus averting any locking or jamming issues.
Belleville Springs for Dynamic Loading and Compensation: Our packing system is equipped with dynamic loading and Belleville springs compensation. The precisely rolled and pressed packing box hole, alongside the meticulously processed stem, eradicates packing emissions, confidently meeting the stringent TA-Luft standards.
Diverse Sealing Options: Choose from a variety of sealing selections, including multi-layer composite, all-metal, and integral all-metal seals. This flexibility allows customization to meet varying service conditions. The multi-layer composite seal provides adaptability, optimizing the fit between seat and sea rings, achieving ANSI VI leakage class compliance.
Thrust Collar Protection: Our stem-protecting thrust collar effectively prevents particle accumulation or coking substances from causing stem jamming. In reverse flow scenarios, it safeguards against rotational displacement due to fluid force, mitigating the risk of increased leakage.
Ease of Maintenance: Precision-engineered parts ensure seamless
on-site adjustment and replacement of seal rings, facilitating effortless maintenance.
SNT Machinery (Qingdao) Co., Ltd. is a distinguished producer of top-tier control valves, seamlessly integrating manufacturing, design, sales, and services under one roof. With a forward-thinking approach and dynamic growth trajectory, SNT thrives in Qingdao, Shandong province, spanning a vast 42,000 m2 area. The facility boasts state-of-the-art workshops and advanced production equipment. A recognized high-tech enterprise, SNT holds independent intellectual property rights, coupled with cutting-edge imported management and production expertise. The workforce exceeds 150 employees, with R&D specialists composing 15%, and 30% holding graduate or higher degrees. Our success stems from a high-quality production management team and pioneering technology R&D, enabling the mass production of premium valves for the petrochemical, oil, and coal chemical sectors. In 2017, we proudly achieved a sales value nearing 100 billion.
SNT proudly holds the TS special equipment manufacturing certificate and ISO 9001 accreditation, complemented by net qualification certifications from industry giants such as SINOPEC, CNOOC, PETROCHINA, and SINOCHEM. Our technological innovation is further validated by numerous National Patents. We excel in designing and manufacturing a comprehensive array of valves adhering to ANSI, API, DIN, BS, and JIS standards. Through blending global valve excellence with independent R&D, we manufacture a diverse spectrum of valves, including GLOBE, High Pressure Boiler Blow-down Valves, High-performance Butterfly Valves, Angle-regulating Valves, and Eccentric Rotary Valves, along with T Three-eccentric Center Butterfly Valves.
Our extensive valve range extends to V Ball Valves, High Wear-resistant Ball Valves, High Pressure Steam Valves, Micro-flow Control Valves, Self-operated Control Valves, and Cryogenic Valves. The driving mechanisms for these valves include manual operation, power-driven, pneumatic, and hydraulic drives. We utilize premier materials such as A216WCB, A217 WC6/WC9, and A351 CF8/CF8M/CF3/CF3M. Specifications range from 1/2" to 120", with a working pressure span of ANSI 150# to 2500#, and operational temperature of -196ºC to 1100ºC.
Thanks to our advanced production technology management and stringent quality assurance systems, SNT Valves have made significant inroads in petrochemical, oil, steel & iron, paper manufacturing, and power station industries. Our distinguished clientele includes SINOPEC QILU branch, SINOPEC Qingdao branch, CNOOC Huizhou Refinery, PETROCHINA Guangxi branch, PETROCHINA Ningxia branch, SINOPEC Qingdao Refinery, and SINOPEC Qingdao branch.
Prioritizing our users' profits, we are unwavering in our commitment to delivering unparalleled quality and establishing a revered brand. Our robust quality assurance and after-sales systems ensure that SNT Valves form enduring partnerships with all our customers, paving the way to collective prosperity.
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