About SNT Butterfly Valves
SNT Machinery (Qingdao) Co., Ltd. boasts a distinctive and innovative design, coupled with cutting-edge processing techniques, and enriched by over a decade of dedicated expertise in the exploration and production of butterfly valves. We are adept at providing tailored solutions for a wide spectrum of complex and demanding service conditions, ensuring our butterfly valves remain powerfully competitive in the market. Our designs align seamlessly with distinguished international standards such as ASME B16.34-2009, GB/T12221-1989, and AP1607-2009. This extraordinary product line finds extensive applications across diverse industries, including petroleum, chemical, light industry, pharmaceuticals, paper manufacturing, metallurgy, and the rubber sector.
Discover the AOC-3812 series triple offset butterfly valve, ingeniously engineered to deliver a bi-directional, bubble-tight shut-off. With its remarkable geometric design, it ensures,
that the disc seal makes contact with the body seat exclusively at the final shut-off position. This prevents any form of rubbing or galling, thereby offering a torque-generative experience,
with a resilient seal equipped with substantial 'wedging' capability to guarantee.
| 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
At the heart of our SNT triple offset butterfly valve lies a sophisticated design that guarantees a bi-directional bubble-tight shut-off. The unique geometry ensures that the disc seal engages the body seat solely at the ultimate shut-off position. This precise alignment eliminates any rubbing or galling, offering a torque-induced resilient seal with optimal 'wedging' action. This innovative mechanism provides an immaculate seal contact that is both dependable and consistent.
The Triple Offset Geometry
Offset 1 - Ingeniously engineered, the shaft is offset behind the seat axis. This design ensures an impeccable sealing contact across the entirety of the seat, delivering a flawless closure every time.
Offset 2 - The shaft centerline is strategically offset from the pipe and valve, enabling interference-free opening and closing of the valve. This precision engineering ensures smooth and seamless operation.
Offset 3 - By offsetting the seat cone axis from the shaft centerline, this design masterfully eliminates friction during both closing and opening phases. It achieves a consistent and compressive sealing effect surrounding the entire seat, ensuring reliability and longevity.
Ingeniously Designed Triple-Eccentric Valves: Engineered to withstand severe service conditions, these valves excel in high temperature and pressure environments while ensuring low leakage. The innovative design allows for frictionless operation and demands minimal torque during opening or closing. Remarkably, as the fluid force increases, the sealing capability enhances, delivering unmatched performance.
Integral Seat Ring and Body Structure: The sealing face is surfaced with high-strength alloy, ensuring exceptional reliability. This robust construction not only fortifies the sealing surface but also significantly extends the valve's life, making it practically maintenance-free.
This design ensures prolonged service life, approaching a state of near non-maintenance, thereby maximizing operational efficiency.
Stepped Sealing for Anti-Blowout Protection: This feature provides unparalleled security. The integral stem, crafted from high-strength material, enhances the valve's capacity to handle allowable pressure drops with precision.
Advanced Stem and Disk Driving Method with Offset Round Pin: By eliminating the need for drilling, the stem's integrity is preserved, significantly boosting the shearing strength and ensuring superior reliability and security.
Stem Sealing Design: Crafted from high-temperature resistant, non-metallic material, the stem seal effectively prevents fluid particles from infiltrating the bearing, thus preventing lockup or jamming, and ensuring smooth operation.
Dynamic Loading and Compensation with Belleville Springs: The packing system employs dynamic loading and compensation using Belleville springs. The packing box hole undergoes rolling and pressing processes, while the stem is meticulously processed to eliminate emissions, adhering to the stringent TA-Luft standards.
Diverse Sealing Options: Select from multi-layer composite seals, multi-layer all-metal seals, or integral all-metal seals, tailored to various service conditions. The multi-layer composite seal offers flexibility for optimal fit between seat and seal rings, meeting ANSI VI leakage class standards.
Thrust Collar Protection: The thrust collar prevents dead angle areas where particles or coking substances might accumulate, thus avoiding stem jamming. When flow reverses, it prevents rational displacement of the stem due to fluid force, thereby reducing the risk of significant leakage.
Effortless Maintenance: The high precision of parts and components ensures seamless on-
site adjustments and replacement of seal rings, enhancing maintenance convenience.
SNT Machinery (Qingdao) Co., Ltd stands as a beacon of innovation and excellence in the production of control valves. As a seamless integration of manufacturing, design, sales, and services, SNT is rapidly advancing with a strong foundation. Strategically nestled in Qingdao, Shandong Province, our expansive 42,000m2 facility boasts state-of-the-art workshops and cutting-edge production equipment. Recognized as a high-tech enterprise, SNT proudly holds independent intellectual property rights and has embraced advanced management and production techniques from around the globe. Our dynamic team exceeds 150 professionals, with 15% dedicated to R&D and 30% holding graduate or higher degrees. Our relentless pursuit of quality and innovation has enabled us to produce a substantial volume of superior valves, catering to industries such as petrochemical, oil, and coal chemical. In 2017, we achieved an impressive sales milestone nearing 100 billion.
SNT has proudly attained the TS Special Equipment Manufacturing Certificate and ISO 9001 certification. We have also secured net qualification certificates from SINOPEC, CNOOC, PETROCHINA, and SINOCHEM, along with several national patents. Our expertise extends to designing and manufacturing a comprehensive range of valves in compliance with ANSI, API, DIN, BS, and JIS standards. By synthesizing the strengths of world-renowned valves with our independent R&D efforts, we've mastered the production of various valves, including GLOBE, High Pressure Boiler Blow-down Valves, High-performance Butterfly Valves, Angle-regulating Valves, Eccentric Rotary Valves, and Three-eccentric Center Butterfly Valves.
Our extensive range also features V Ball Valves, High Wear-resistant Ball Valves, High Pressure Steam Valves, Micro-flow Control Valves, and Self-operated Control Valves, all available with manual, electric, pneumatic, and hydraulic actuation. Crafted from premium materials like A216WCB, A217 WC6/WC9, A351 CF8/CF8M/CF3/CF3M, our valves accommodate specifications from 1/2" to 120" withstanding pressures ANSI 150#~2500# and temperatures from -196ºC to 1100ºC.
Embracing advanced production technology and robust quality assurance systems, SNT Valves are trusted by industries spanning petrochemical, oil, steel & iron, paper manufacturing, and power stations. Our esteemed client base includes giants such as SINOPEC (QILU and Qingdao branches), CNOOC Huizhou Refinery, PETROCHINA (Guangxi and Ningxia branches), and more.
At SNT, we prioritize our clients' success and are committed to creating outstanding quality and a reputable brand. Our rigorous quality assurance and exceptional after-sales systems ensure that SNT valves form enduring partnerships with all our customers, fostering shared prosperity and growth.
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