Triple Eccentric Butterfly Valve | Triple Offset | WCB CF8M Duplex | Metal Seat Stellite | API 609 Cat B | Fire Safe | Supplier India

Description

Triple Eccentric Butterfly Valve Supplier India | Triple Offset | WCB / CF8M / Duplex | Metal Seat / Stellite / Inconel | API 609 Category B | Fire Safe | DN50–DN1200 | KELOR

Supplier: Krishna Industries (KELOR) – Ahmedabad, Gujarat, India
Established: 2017 | GSTIN: 24AKLPP6499B1ZT | IEC: AKLPP6499B
MOQ: 10 Nos | Body: WCB / CF8M / Duplex / Super Duplex
Standard: API 609 Category B | Fire Safe: API 607 / API 6FA | Sizes: DN50–DN1200

Triple Eccentric Butterfly Valve Supplier in India

Krishna Industries (KELOR), based in Ahmedabad, Gujarat, is a B2B supplier of Triple Eccentric Butterfly Valves (Triple Offset Butterfly Valves) — WCB, CF8M (SS316), Duplex, Super Duplex body — SS316 metal laminated seat (standard), Stellite hard face, PTFE seat ring, Inconel on request — API 609 Category B — fire safe to API 607 / API 6FA — ISO 15848 fugitive emissions — double flanged, lug, wafer type — DN50 to DN1200 — Class 150 / Class 300 / Class 600 — ASME B16.34 — API 598 tested — GST invoice — MOQ 10 Nos — Pan India dispatch from Ahmedabad.

The triple eccentric butterfly valve is the metal-seated, high-performance butterfly valve for power plant, refinery, petrochemical, steel plant, and offshore service — zero leakage metal-to-metal seating, fire safe construction, cam-action closure with no seat wear throughout the 90° travel, suitable for steam to 450°C, high pressure Class 600, and corrosive process media where conventional rubber or PTFE seated butterfly valves fail.

What Makes It Triple Eccentric — The Three Offsets Explained

The performance of a triple eccentric butterfly valve is entirely defined by its three geometric offsets. Understanding these offsets explains why this valve achieves zero leakage with a metal seat — which no concentric or double eccentric butterfly valve can achieve.

First Eccentricity — Shaft Offset from Disc Centreline

The shaft does not pass through the centreline of the disc — it is offset to one side. When the shaft rotates, only one half of the disc face contacts the seat at any time during the stroke. This halves the seating surface area in contact at any moment, reducing friction and wear compared to a concentric design where the full disc circumference rubs against the seat throughout the entire 90° travel.

Second Eccentricity — Shaft Offset Behind the Sealing Plane

The shaft axis sits behind the sealing face of the disc. As the disc begins to open from the closed position, the sealing face immediately moves away from the seat in an arc, breaking contact cleanly at the start of the opening stroke. Combined with the first eccentricity, the disc virtually lifts away from the seat from the first degree of rotation — no dragging, no scraping.

Third Eccentricity — The Oblique Cone Seating Surface

This is the defining characteristic of the triple eccentric design. The sealing surface is not a simple right-angle cone but an oblique cone — the cone axis is inclined at an angle to the pipe centreline. As the disc closes, its sealing face traces the geometry of this oblique cone and approaches the seat ring in a cam action — contacting the seat only at the very final degree of closure, not during any earlier part of the 90° rotation.

The result: there is no sliding contact between disc and seat throughout the entire 90° travel. Contact occurs only at the final seating moment — like a cone being pressed into a matching socket. This cam action is what makes metal-to-metal seating possible without wear — no elastomer required, no rubbing to erode the seat, no leakage path developing over time.

Triple Eccentric vs Concentric vs Double Eccentric — Comparison

Body and Trim Material Selection Guide

Technical Specifications

Triple Eccentric Butterfly Valve vs Gate Valve — The Replacement Case

Large bore gate valves at DN300 to DN600, Class 150/300 are the traditional isolation valve in Indian power plants and refineries. The case for replacing them with triple eccentric butterfly valves is now well established in Indian EPC project specifications:

• Weight: a DN400 Class 300 TOBV weighs approximately 60–70% less than an equivalent gate valve — reduces pipe support loads and structural steel cost in new plants
• Face-to-face length: a DN400 TOBV double flanged has a face-to-face of approximately 300mm — the equivalent gate valve is 4–5 times longer — significant in congested pipework
• Actuation: quarter turn (90°) operation vs gate valve multi-turn — smaller, lighter actuator for same DN and Class — lower actuator cost
• Maintenance: no stem gland to adjust, no wedge seating surface to regrind, no stem threads to lubricate — maintenance interval significantly longer than gate valve
• Cost at DN300+: TOBV Class 150/300 at DN300 and above is significantly less expensive than equivalent gate valve — the cost crossover point versus standard butterfly valve disappears at large bore high pressure service because gate valve cost escalates sharply

Indian EPC contractors for NTPC, BHEL, IOCL, and HPCL projects increasingly specify TOBV in plant layouts at Class 150 DN300+ where gate valves were previously standard. Enquiries for these projects can specify body material, seat material, Class, size range, and API 609 Category B with fire safe certificate for direct quotation.

Applications in Indian Industries

• Thermal power plants — WCB + SS316/graphite seat — Class 150/300 — auxiliary steam headers, BFP recirculation, condensate extraction, LP/HP heater drain and vent, cooling water isolation — BHEL, NTPC, Adani, Tata Power project specifications
• Oil refineries — WCB + Stellite or SS316 seat — Class 150/300/600 — crude distillation auxiliary headers, hydrocarbon process utility, fire safe required (API 607 certificate) — IOCL, HPCL, BPCL, Reliance, Nayara project specifications
• Petrochemical plants — WCB / CF8M + SS316 or Stellite — Class 150/300 — process utility headers, corrosive chemical process, fire safe hydrocarbon service — ONGC, GAIL, OPAL, RIL specifications
• Steel plants — WCB + Stellite — Class 150/300 — blast furnace gas, coke oven gas, BOF gas — abrasive dusty gas service — high wear resistance needed
• Fertilizer plants — WCB / CF8M — Class 150/300 — ammonia, urea process headers, high pressure synthesis loop — NH3 compatible materials required
• Offshore and marine — Duplex or Super Duplex + Stellite — Class 150/300 — seawater utility, fire water, production fluid headers — fire safe mandatory (API 6FA), chloride resistance mandatory
• LNG terminals — LCB low temperature body — Class 150/300 — cryogenic service — Charpy impact tested for -46°C
• Chemical and pharma large bore headers — CF8M + SS316/graphite or PTFE seat — Class 150 — corrosive process headers where CI body is not acceptable

Related Products — Krishna Industries (KELOR)

• Gear Operated Butterfly Valve — CI/WCB — concentric design, EPDM/PTFE seat — PN10/PN16 — for general industrial service where triple eccentric is not required
• Teflon Lined Butterfly Valve — CI/WCB Body — Class 150 PTFE seat — chemical service at moderate pressure and temperature
• Stainless Steel Butterfly Valve — CF8/CF8M Body — full SS body, EPDM/PTFE seat — food, pharma, DM water, coastal — PN16/Class 150
• Flanged Ball Valve — WCB/CF8M — for smaller bore Class 150/300 on-off isolation where butterfly valve is oversized
• WCB Globe Valve — for throttling service in smaller bore process lines

Frequently Asked Questions

1. What is the difference between API 609 Category A and Category B?

API 609 Category A covers concentric and double eccentric butterfly valves — soft seated (elastomer or PTFE) — generally limited to Class 150/300 and temperatures below 250°C. API 609 Category B covers triple eccentric butterfly valves with metal-to-metal seating — Class 150 through Class 600 — temperatures to 593°C — fire tested to API 607 or API 6FA. Indian refinery, power plant, and petrochemical project specifications that require fire safe butterfly valves will always specify API 609 Category B — this is the standard for any hydrocarbon or high temperature butterfly valve application.

2. Is a triple eccentric butterfly valve fire safe?

Yes — inherently fire safe. In a fire, any PTFE or rubber seat material burns, but the metal body and metal seat ring remain intact. The cam-action metal-to-metal contact continues to provide shut-off after the non-metallic elements have been consumed. Fire safe test certificates to API 607 or API 6FA can be provided. Indian oil and gas and petrochemical project specifications — ONGC, IOCL, HPCL, BPCL, GAIL — require fire safe certification for all hydrocarbon butterfly valves. This certificate distinguishes triple eccentric from any concentric or double eccentric butterfly valve, which cannot pass the fire test with a soft seat alone.

3. Why specify Stellite hard face over standard SS316 seat?

SS316 metal seat is adequate for most clean fluid service up to 400°C. Stellite 6 (a cobalt-chromium alloy, HRC 40+) is specified for erosive or abrasive service — HP steam with entrained moisture, wet steam flash service, high velocity letdown, dirty or particle-laden process streams. In power plant HP heater drain and turbine bypass service, wet steam at high velocity erodes the SS316 seating surface progressively over cycles. Stellite resist erosion and galling far better than SS316 — significantly extending valve service life in these applications.

4. Can triple eccentric butterfly valve replace gate valve on Indian power plant projects?

Yes — and this is increasingly the standard specification for Indian thermal power plant auxiliary services at DN300 and above, Class 150/300. WCB body, SS316/graphite laminated seat, double flanged, gear operated, API 609 Category B, API 598 tested, ISO 5211 pad — this is the standard TOBV specification replacing gate valves on NTPC, BHEL, and private IPP project auxiliary steam, condensate, and cooling water headers. The cost, weight, and space savings at DN300–DN600 are substantial. WhatsApp size list, Class, and service for project pricing.

5. What is the MOQ?

MOQ is 10 Nos total. Power plant or refinery project orders — 20 to 200+ Nos across sizes — with API 609 Category B certification, API 598 test reports, fire safe certificate (API 607 / API 6FA), material test reports (MTR), and GST invoice. Specify body material, disc/seat material, Class, size list, end connection, and actuator requirement for project pricing within 4 hours.

Conclusion

The Triple Eccentric Butterfly Valve supplied by Krishna Industries (KELOR) is the API 609 Category B metal-seated butterfly valve for Indian power plant, refinery, petrochemical, steel plant, and offshore service — WCB, CF8M, Duplex, Super Duplex body — SS316/graphite laminated seat (standard), Stellite hard face, PTFE seat ring, Inconel on request — zero leakage cam-action metal-to-metal closure — fire safe API 607 / API 6FA — ISO 15848 fugitive emissions — double flanged, lug, wafer — DN50 to DN1200 — Class 150 / 300 / 600 — API 598 tested — MTR on request. GST invoice, Pan India dispatch from Ahmedabad. WhatsApp body material, disc/seat, Class, size list, and fire safe certificate requirement for project pricing within 4 hours.