About SNT Butterfly Valves
SNT Machinery (Qingdao) Co., Ltd. is a leader in the butterfly valve industry, known for its unique designs and advanced manufacturing techniques. With over a decade of expertise, we specialize in crafting high-quality butterfly valves that tackle complex and harsh service conditions with ease. Our valves stand out in the global market with their robust competitiveness, adhering to international standards such as ASME B16.34-2009, GB/T12221-1989, and AP1607-2009. This prestigious series is extensively utilized across various sectors including petroleum, chemical, light industry, pharmaceuticals, paper production, metallurgy, and rubber industries, showcasing our versatility and reliability.
The AOC-3812 series triple offset butterfly valves are engineered to deliver exceptional performance, featuring a bi-directional bubble-tight shut-off capability. The innovative design ensures flawless operation,
where the disc seal precisely engages with the body seat only during the final shut-off phase, minimizing wear and tear for an enduring lifespan, contributing to a reliable and efficient torque.
This results in a dynamically generated resilient seal, enhanced by optimal 'wedging' action to guarantee secure closure and prevent leaks, even in the most demanding applications.
| 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
SNT's innovative triple offset butterfly valve delivers a bi-directional, bubble-tight shut-off. Its unique geometry ensures that the disc seal interacts with the body seat exclusively at the final shut-off position, eliminating rubbing or galling. This design offers a torque-induced resilient seal with ample 'wedging,' guaranteeing consistent and uniform seal contact.
The Triple Offset Geometry
Offset 1 - Ingeniously designed, the shaft is positioned behind the seat axis, enabling thorough and complete sealing contact around the entire seat. This meticulous design ensures optimal performance and reliability.
Offset 2 - The shaft centerline is strategically offset from the pipe and valve, facilitating interference-free opening and closing of the valve. This design enhances operational efficiency and prolongs the valve's lifespan.
Offset 3 - The seat cone axis is cleverly offset from the shaft centerline, removing friction during closing and opening. This ensures a uniform compressive seal around the entire seat, promoting seamless operation and durability.
Ingeniously engineered with a triple-eccentric design, this valve excels in enduring the most extreme service conditions, including high temperature and pressure, while ensuring minimal leakage. Its unique opening and closing mechanism is characterized by non-friction movement and low torque, seamlessly enhancing sealing performance as fluid force increases.
The seat ring and valve body are meticulously crafted as an integral structure. This design features a high-strength alloy surfacing on the sealing face, ensuring unparalleled reliability and durability.
This superior construction significantly extends the service life, approaching a state of near-zero maintenance requirements.
To counteract blowout risks, a stepped seal design is employed. This guarantees safety, while the robust integral stem, constructed from high-strength materials, enhances the valve's capacity to withstand substantial pressure drops.
Employing an offset round pin for the stem and disk driving method, this design cleverly avoids the weakening of the stem's strength due to drilling. It bolsters the shearing strength of the round pin, ensuring heightened reliability and security.
Stem sealing is expertly designed using high-temperature resistant, non-metallic materials, preventing particle-laden fluids from entering the bearing. This effectively avoids the risk of seizing or jamming.
With dynamic loading and compensation provided by Belleville springs, the packing system is state-of-the-art. Utilizing rolling and pressing techniques in the packing box hole, combined with meticulous stem processing, this design eliminates packing emissions, meeting the stringent TA-Luft standard.
Offering a variety of sealing options, including multi-layer composite, all-metal, and integral all-metal seals, this valve is adaptable to diverse service conditions. The multi-layer composite seal is particularly flexible, ensuring an impeccable fit between the seat and seal ring, achieving ANSI VI leakage class standards.
The thrust collar ingeniously safeguards the stem by preventing particle or coking substance accumulation in the dead angle area between stem and body. In reverse flow scenarios, it adeptly prevents rational displacement of the stem due to fluid force, averting large leakage incidents.
Convenient maintenance is assured through the high precision of parts, allowing for seamless on-
site adjustment and replacement of seal rings, ensuring the valve's performance remains consistently optimal.
SNT Machinery (Qingdao) Co., Ltd is a distinguished manufacturer specializing in control valves. We seamlessly integrate manufacturing, design, sales, and services to offer a robust solution for your needs. Strategically located in Qingdao, Shandong province, our expansive 42,000m² facility is outfitted with cutting-edge workshops and state-of-the-art production equipment. As a high-tech enterprise, we boast independent intellectual property rights and leverage international best practices in management and production. Our team comprises over 150 skilled professionals, with 15% dedicated to R&D and 30% holding graduate or higher degrees. With a focus on superior production management and pioneering technology, we excel in producing high-quality valves extensively applied in petrochemical, oil, and coal chemical industries. In 2017, we achieved a remarkable sales value nearing 100 billion.
SNT is proud to hold the TS Special Equipment Manufacturing Certificate and ISO 9001 certification, alongside net qualification certificates from industry giants like SINOPEC, CNOOC, PETROCHINA, and SINOCHEM. Our technological innovations have garnered numerous national patents. We expertly design and manufacture a comprehensive range of valves adhering to ANSI, API, DIN, BS, and JIS standards. By synthesizing global valve advantages with our independent R&D efforts, we produce a wide array of valves, including GLOBE, High-Pressure Boiler Blow-down Valves, High-Performance Butterfly Valves, Angle-Regulating Valves, and Eccentric Rotary Valves.
Our product line also features T Three-Eccentric Center Butterfly Valves, 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 forms encompass manual operation, power-driven, pneumatic, and hydraulic options. The primary materials used are A216WCB, A217 WC6/WC9, A351 CF8/CF8M/CF3/CF3M, etc. Specifications range from 1/2" to 120", with working pressures of ANSI 150# to 2500#, and operating temperatures from -196ºC to 1100ºC.
Underpinned by advanced production technology and a rigorous quality assurance system, SNT valves are integral to sectors including petrochemical, oil, steel & iron, paper manufacturing, and power stations. Our esteemed clientele includes SINOPEC QILU, Qingdao branches, CNOOC Huizhou Refinery, PETROCHINA Guangxi and Ningxia branches, among others.
We prioritize our users' profitability, committing ourselves to exemplary quality and brand excellence. Our comprehensive quality assurance and after-sales service systems ensure that SNT valves forge prosperous partnerships with all our valued customers.
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