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Дисковые затворы

4.4 / 5 (26 reviews)
API 609BS EN 593
Size Range
2" - 60"
Pressure Class
Class 150 - 600
Standards
API 609, BS EN 593
Materials
Carbon Steel (A216 WCB), Stainless Steel (A351 CF8M), Duplex (A890 4A)

Product Range

Select a series for detailed specifications, downloads and technical data.

Дисковый затвор с тройным эксцентриситетом и металлическим уплотнением

Дисковый затвор с тройным эксцентриситетом и металлическим уплотнением

2" – 48" (DN50 – DN1200)

2" - 48"Class 150 - 1500
Пневматический дисковый затвор с центральным расположением диска

Пневматический дисковый затвор с центральным расположением диска

Размеры: 2" – 24" (DN50 – DN600)

Class 150, PN10,PN16
Межфланцевый дисковый затвор с проушинами (центрический)

Межфланцевый дисковый затвор с проушинами (центрический)

Размеры: 2" – 24" (DN50 – DN600)

Class 150, PN10,PN16
Межфланцевый дисковый затвор с двойным эксцентриситетом

Межфланцевый дисковый затвор с двойным эксцентриситетом

2" – 48" (DN50 – DN1200)

2" - 48"Class 150 - 1500
Дисковый затвор с тройным эксцентриситетом и многослойным уплотнением

Дисковый затвор с тройным эксцентриситетом и многослойным уплотнением

Размер: 2" – 48" (DN50 – DN1200)

2" - 48"Class 150 - 1500
Дисковый затвор с кованым корпусом и металлическим уплотнением

Дисковый затвор с кованым корпусом и металлическим уплотнением

Размер: 2" – 12" (DN50 – DN300)

2" - 48"Class 150 - 1500
Межфланцевый дисковый затвор стяжного типа (Lug) с многослойным седлом

Межфланцевый дисковый затвор стяжного типа (Lug) с многослойным седлом

Размер: 2" – 24" (DN50 – DN600)

2" - 48"Class 150 - 1500
Эксцентриковый дисковый затвор под приварку встык

Эксцентриковый дисковый затвор под приварку встык

Quick Specs Size: 2" - 24" (DN50 - DN600) Pressure: Class 150 - 600 / PN 10-100 Standard: ASME B16.34, API 609, ISO 15848 Body Materials: A216 WCB, A182 F316 (forged for smaller sizes), A351 CF8M Seat: Metal-to-metal (Stellite 6 overlay) or multi-layer composite seat (metal base + flexible graphite) Design: Butt-weld end connections (beveled per ASME B16.25), double eccentric or triple eccentric geometry No Flanges, No Gaskets, No Leak Paths Every flanged connection has two failure points: the gasket and the bolts. Gaskets age and compress unevenly. Bolts relax under thermal cycling, lose preload, and the gasket drops below sealing compression—now you've got a leak path you can't see until it shows up as emissions or a drip on the floor. At Class 600+, flanged connections require heavy bolting and thick gaskets, and they're still the weakest seal in the line. Butt-weld ends eliminate both. Valve ends are beveled per ASME B16.25. Weld them directly to the pipe. No gasket between valve and pipeline. No bolt pattern to maintain. No external leak path. Once the weld is made, inspected, and accepted, that connection is permanent. It doesn't age. It doesn't relax. It doesn't leak. This matters in three scenarios. Class 600+ high-pressure lines where every flange is a maintenance item and emissions source. Buried or submerged installations where bolt retorquing requires excavation. Fire-safe systems where gaskets burn—welded joints don't. Welded In Means Permanent The tradeoff is straightforward. A butt-welded butterfly valve cannot be removed without cutting it out. When you weld this valve into the line, it becomes a permanent pipeline component. That's why some installations specify butt-welded ends. Underground vaults, submarine crossings, high-pressure fire-safe lines where you want minimum external leak points—permanent installation is the correct engineering choice. You plan for it to stay for the life of the pipeline. If your installation requires periodic valve removal, specify flanged ends. Butt-welded is for permanent service. Eccentric Geometry Protects Both Seat Types Cam-action disc rotation from double or triple eccentric geometry lifts the disc off the seat immediately instead of sliding. For the Stellite 6 metal-to-metal seat, that means no grinding across the hard facing every cycle—the overlay survives abrasive and high-temperature service. For the multi-layer composite seat, the graphite layer isn't scraped away during rotation—bubble-tight performance holds across thousands of cycles. Lower seat friction also reduces operating torque. Smaller actuators, easier manual operation. On a valve permanently installed in an underground vault, lower torque means no oversizing—less weight, less maintenance in inaccessible locations. FAQ A: Zero external leak path at the valve-to-pipeline connection. No gasket, no bolts, no mechanical seal that relaxes over time. The welded joint is permanent and code-compliant. A: Only by cutting the welds. This is a permanent installation valve. If the application requires periodic removal, specify flanged ends. A: Metal-to-metal Stellite 6 for high-temperature, abrasive, or cycling service above 500°F where fire-safe certification is required and ambient leakage tolerance is acceptable. Multi-layer composite when you need both fire-safe and bubble-tight at ambient in the same valve. A: Valve ends are beveled per ASME B16.25. Welding procedures, filler materials, and PWHT must comply with ASME B31.3 or applicable project code. WCB uses standard carbon steel procedures. F316 requires stainless filler and controlled heat input. A: Yes. Butt-welded ends are preferred for buried and submerged piping—no gaskets to leak, no bolts to corrode. Specify external coatings per project requirements for the body material in that environment.

2" - 48"Class 150 - 1500

Technical Overview

Butterfly valves rotate a disc 90° inside the flow path to open or close—the simplest quarter-turn mechanism in industrial valve design. That simplicity is the reason butterfly valves dominate water, HVAC, and general process isolation: one moving part, one 90° stroke, one sealing interface, minimal space envelope, lowest cost per diameter inch of any shutoff valve type. FLOWKS manufactures eight butterfly valve configurations spanning three sealing philosophies and three body connection formats. Concentric (centerline) designs align the shaft, disc, and body on the same axis—the disc slides across the seat surface during rotation, simple and cheap but limited in pressure rating and cycle life. Double eccentric (high-performance) designs offset the shaft in two planes so the disc cam-lifts off the seat during opening, reducing rubbing and extending elastomer seat life by 3-5x. Triple eccentric designs offset the shaft in three planes so the disc only contacts the seat at the final 2-3° of closing—frictionless travel that enables metal-to-metal seating for high-temperature and fire-safe service. Seat types range from resilient elastomer liners (EPDM, NBR, Viton—bubble-tight, low-cost, temperature-limited) through metal seats (Stellite 6 overlay—fire-safe, high-temperature, slight ambient leakage) to multi-layer composite seats (metal base ring + flexible graphite layer—bubble-tight at ambient AND fire-safe under fire conditions). Body connections include wafer (sandwich between flanges, slimmest, cheapest), lug (threaded ears, one-side isolation capability), and butt-weld (permanent welded-in installation, zero external leak paths). Pneumatic, electric, hydraulic, and manual actuation options cover the full range of process automation requirements.

FLOWKS butterfly valves provide quarter-turn shutoff across the widest range of process conditions—from HVAC water isolation at Class 150 to petrochemical high-pressure high-temperature service at Class 900. Concentric centerline butterfly valves with resilient elastomer liners deliver cost-effective bidirectional sealing for water, wastewater, and light-process applications. Double eccentric high-performance butterfly valves reduce seat friction through cam-action disc rotation, extending elastomer cycle life and enabling Class 150-300 service with tighter shutoff. Triple eccentric butterfly valves with metal-to-metal Stellite seats eliminate elastomer entirely—rated for 350°C+ continuous temperature, fire-safe per API 607, ISO 15848 low-leakage fugitive emission compliant. Multi-layer composite seats combine bubble-tight ambient sealing with fire-safe metal backup for petrochemical installations that demand both capabilities. Wafer bodies offer the slimmest installation footprint between pipeline flanges. Lug bodies enable dead-end service and one-side isolation through independent threaded flange ears. Butt-welded ends eliminate flange gaskets entirely for permanent high-pressure and buried installations. Forged body construction provides casting-free pressure boundary integrity for severe service at small sizes. Pneumatic, electric, hydraulic, and manual gear actuation available across all configurations.