About SNT Butterfly Valves
SNT Machinery (Qingdao) Co., Ltd. boasts a remarkable combination of unique design and advanced processing methodologies, supported by over a decade of expertise in the exploration and manufacture of superior butterfly valves. Our commitment allows us to deliver innovative solutions tailored to the most challenging and severe service conditions. Our butterfly valves not only hold significant market competitiveness but also strictly adhere to revered international standards such as ASME B16.34-2009, GB/T12221-1989, and AP1607-2009. These exceptional products are extensively utilized across a multitude of industries including petroleum, the chemical sector, light industrial applications, pharmaceuticals, paper production, metallurgy, and rubber manufacturing.
Experience the cutting-edge AOC-3812 series triple offset butterfly valve, designed to deliver impeccable bi-directional bubble-tight shut-off. This advanced geometry guarantees flawless performance.
It ensures that the disc seal comes into contact with the body seat exclusively at the final shut-off position, eliminating any risk of rubbing or galling. This feature ensures a consistently reliable and efficient torque operation.
The valve's design incorporates a torque-generated resilient seal, ingeniously crafted with ample 'wedging' to secure an unequivocal and enduring seal.
| 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 for excellence, delivering a bi-directional, bubble-tight shut-off that you can rely on. The ingenious geometry of this valve ensures that the disc seal seamlessly contacts the body seat exclusively at the final shut-off position. This design eliminates any potential for rubbing or galling, allowing for a torque-generated resilient seal. The result is a robust 'wedging' action that guarantees a consistently uniform seal contact, elevating operational efficiency and reliability.
The Triple Offset Geometry
Offset 1 - Ingeniously designed, the shaft is positioned offset behind the seat axis, facilitating complete and flawless sealing contact around the entire seat. This precision ensures the valve's unparalleled sealing efficiency.
Offset 2 - Uniquely engineered, the shaft centerline is offset from the pipe and valve, providing interference-free operation for both opening and closing. This guarantees smooth performance without compromise.
Offset 3 - The seat cone axis is strategically offset from the shaft centerline. This sophisticated design eliminates friction during both closing and opening phases, ensuring uniform compressive sealing around the entire seat, for unmatched efficiency and durability.
Innovative Design of Triple-Eccentric: Engineered for the most demanding conditions, our triple-eccentric design effortlessly withstands high temperatures and pressures, ensuring minimal leakage. With its frictionless operation and low torque requirement during opening or closing, the valve excels in performance. The greater the fluid force, the more exceptional the sealing efficiency becomes, offering unparalleled reliability in challenging environments.
Robust Integral Structure of Seat Ring and Body: Crafted with a high-strength alloy surfacing on the sealing face, this design guarantees long-lasting reliability. The integrity of the sealing face is preserved, significantly extending the service life of the valve, and thereby approaching a state of near non-maintenance to deliver consistent performance.
and durability, reducing the need for frequent maintenance.
Advanced Stepped Sealed for Anti-Blowout: Designed to ensure maximum safety, this feature uses a high-strength integral stem to enhance pressure drop tolerance, providing robust security and reliability in diverse applications.
Offset Round Pin Stem and Disk Drive Method: This innovative approach prevents the weakening of the stem's strength due to drilling, enhancing the shearing strength and overall reliability of the round pin. This not only boosts reliability but also secures the valve's function, ensuring optimal performance.
High-Performance Stem Sealing Design: Utilizing high-temperature resistant non-metallic materials, this sealing design effectively prevents particulates from infiltrating the bearing, reducing the risk of lock-up or jamming. This ensures smooth and uninterrupted operation even in particle-laden environments.
Dynamic Loading and Compensation with Belleville Springs: Incorporating Belleville springs for dynamic loading and compensation, our advanced packing system meets TA-Luft standards. The packing box is meticulously crafted using rolling and pressing techniques, and the stem undergoes precision processing to eliminate emissions.
Versatile Sealing Options: Choose from multi-layer composite sealed, all-metal sealed, and integral all-metal sealed options based on specific service conditions. The multi-layer composite sealed option offers flexibility for superior fit between seat ring and sea ring, achieving ANSI VI leakage class compliance for optimal sealing.
Protective Thrust Collar: Designed to thwart particle accumulation or coking substance buildup, the thrust collar prevents dead angles and potential stem jamming. In reverse flow, it protects against stem displacement due to fluid force, effectively minimizing leakage risk and enhancing reliability.
Convenient Maintenance and Precision Parts: Achieve high precision
with on-site regulation and simple replacement of seal rings, ensuring minimal disruption and maximum efficiency.
SNT Machinery (Qingdao) Co., Ltd. is a premier producer of top-tier control valves, seamlessly integrating manufacturing, design, sales, and services. Positioned for rapid growth from a high starting point, SNT is situated in Qingdao, Shandong province, sprawling across 42,000m2. Our state-of-the-art facilities boast modern workshops and cutting-edge production equipment. As a high-tech enterprise with proprietary intellectual property rights, we leverage imported advanced management and production methodologies. Our dynamic team comprises over 150 skilled employees, with R&D specialists representing 15% and 30% holding graduate or higher degrees. Dedicated to excellence, our high-quality production management team and innovative research propel us to deliver high-performance valves for the petrochemical, oil, and coal chemical sectors, achieving nearly 100 billion in sales value in 2017.
SNT proudly holds the esteemed TS special equipment manufacturing certificate and ISO 9001 accreditation. We are also a certified supplier for SINOPEC, CNOOC, PETROCHINA, and SINOCHEM. Our commitment to innovation is reflected in our numerous national patents. We design and manufacture a comprehensive range of valves in adherence to ANSI, API, DIN, BS, and JIS standards. By synthesizing the strengths of globally renowned valves with our own R&D, we produce an extensive array of valves, including GLOBE, High Pressure Boiler Blow-down Valves, High-performance Butterfly Valves, Angle-regulating Valves, and Eccentric Rotary Valves, 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, Cryogenic Valves, and more. Our driving mechanisms range from manual to power-driven, pneumatic, and hydraulic options. Key materials include A216WCB, A217 WC6/WC9, and A351 CF8/CF8M/CF3/CF3M, with specifications from 1/2" to 120", supporting working pressures of ANSI 150# to 2500#, and temperatures ranging from -196ºC to 1100ºC.
Leveraging advanced production technology and a robust quality assurance system, SNT Valves are trusted across industries such as petrochemical, oil, steel & iron, paper manufacturing, and power generation. Our esteemed clientele includes SINOPEC QILU branch, SINOPEC Qingdao branch, CNOOC Huizhou Refinery, PETROCHINA Guangxi branch, PETROCHINA Ningxia branch, SINOPEC Changling branch, and Jinan branch, attesting to our commitment to quality and reliability.
At the core of our philosophy is prioritizing user profitability. We are dedicated to establishing an outstanding reputation for quality and brand excellence. Our robust quality assurance and after-sales service systems ensure that SNT valves not only meet but exceed customer expectations, fostering prosperous partnerships for mutual success.
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