Extended Stem Butterfly Valve Supplier India | Underground Buried Valve Pit Insulated Pipe | CI DI Body SS304 SS316 Disc | Gear Lever Operated | DN50–DN300 | KELOR

Description

Extended Stem Butterfly Valve Supplier India | Underground Buried / Valve Pit / Insulated Pipe | CI / DI Body | SS304 / SS316 Disc | Gear & Lever Operated | DN50–DN300 | PN10–PN16 | KELOR

Supplier: Krishna Industries (KELOR) – Ahmedabad, Gujarat, India
Established: 2017 | GSTIN: 24AKLPP6499B1ZT | IEC: AKLPP6499B
MOQ: 10 Nos | Body: CI IS 210 / DI ASTM A536
Disc: SS304 / SS316 | Extension: 200mm–3000mm — specify at order

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Extended Stem Butterfly Valve Supplier in India

Krishna Industries (KELOR), based in Ahmedabad, Gujarat, supplies Extended Stem Butterfly Valves — standard butterfly valve body with extension spindle and column for inaccessible installations — CI (IS 210) and DI (ASTM A536) body — SS304 / SS316 disc — EPDM / NBR / PTFE seat — gear operated and lever operated — extension length 200mm to 3000mm — DN50 (2″) to DN300 (12″) — PN10 / PN16 — GST invoice — MOQ 10 Nos — Pan India dispatch from Ahmedabad.

An extended stem butterfly valve is a standard butterfly valve fitted with an extension spindle — and typically an extension column for longer lengths — that raises the operating point (handwheel, gearbox, or lever) from the valve body to an accessible location. Furthermore, this configuration is required wherever the valve body is inaccessible after installation — underground buried pipelines, submerged valve pits, thermally insulated chilled water piping, and fire-insulated HVAC risers. Consequently, the correct extension length must be measured and specified at order stage — it cannot be adjusted after manufacturing.

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When Is an Extended Stem Butterfly Valve Required?

Installation Type	Why Standard Stem Is Insufficient	Extension Arrangement	How to Measure Extension Length
Underground Buried Pipeline	Valve buried 0.5m–2m below ground — standard stem too short to reach surface — operator cannot access valve without excavation	Extension spindle + column from valve to surface — CI or GI kerb box (surface box) at ground level — T-bar or kerb key operation at surface	✅ Measure from valve centreline to ground surface level — this is the extension length — add 100mm for kerb box operating nut height above ground — typical range: 600mm–2000mm
Valve Pit (Underground Chamber)	Valve installed in concrete pit — pit has access cover at surface — valve body inaccessible without entering pit — operator access from surface required	Extension spindle from valve top to pit access cover level — gearbox or lever at top of extension — operator turns valve from surface through pit access opening	✅ Measure from valve stem top to pit cover operating level — typical range: 500mm–1500mm — confirm pit cover opening size is adequate for gearbox handwheel or lever at top of extension
Thermal Insulation — Chilled Water Pipe	Chilled water pipe insulated with Armaflex or closed cell foam after valve installation — insulation covers standard stem — valve not operable without cutting insulation	Short extension spindle raising operator interface beyond insulation face — insulation applied around extension column — operator accesses lever or gearbox above insulation surface	✅ Measure insulation thickness at valve location (typically 25mm–100mm depending on pipe size and ambient design) — add 50mm operating clearance beyond insulation face — typical extension: 75mm–150mm total
Fire Insulation — HVAC Riser	HVAC riser pipework in building fire shaft protected with mineral wool fire insulation — insulation 50mm–150mm thick — standard stem buried after insulation application	Extension spindle through fire insulation — fire-rated extension column or ceramic fibre packing at insulation penetration — gearbox or lever above insulation surface	✅ Measure fire insulation specification thickness from the building fire protection drawing — add 50mm operating clearance — typical extension: 100mm–200mm total — confirm fire insulation penetration detail with project fire consultant

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How to Specify Extension Length — The Critical Ordering Step

Extension length is the most important parameter on an extended stem butterfly valve order. Moreover, it is the parameter most frequently left unspecified or incorrectly estimated. Since the extension spindle is manufactured to a specific length, the valve cannot be adjusted on site after installation.

Step-by-Step Measurement Guide

For underground buried valves: Measure the depth from the top of the pipeline (valve centreline) to the finished ground surface level. Add 100mm for the kerb box operating nut height. This total is the extension length to specify.

For valve pit installations: Measure from the top of the valve stem to the pit cover operating level. Confirm that the gearbox handwheel or lever at the top of the extension clears the pit opening before ordering.

For insulated piping: Check the insulation specification on the mechanical drawing for insulation thickness at the valve location. Add 50mm clearance above the insulation face. This total is the extension length to specify.

If extension length is uncertain: Always round up — a slightly longer extension is manageable; a short extension cannot reach the operating point and requires a new valve. Furthermore, provide a site sketch or photograph with the WhatsApp enquiry — we advise on correct extension length based on site conditions.

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Extension Stem Configuration Options

Component	Specification	When Required
Extension Spindle	SS304 or SS316 rod — connected to valve stem at bottom — to operator at top — length as specified	All extended stem applications — standard component of every extended stem configuration
Extension Column / Standpipe	MS GI or SS tube surrounding spindle — provides mechanical protection and alignment guidance for spindle	Required for extensions above 500mm (buried and deep pit) — protects spindle from soil load and bending — guides spindle for reliable operation at depth
Kerb Box / Surface Box	CI or GI IS 3950 surface box — installed at ground level over extension column — protects from traffic and ground load — standard municipal water board spec	Underground buried valve — surface access for T-bar or kerb key operation — standard for Indian municipal water supply buried butterfly valves
Gearbox at Extension Top	Worm gear gearbox mounted at top of extension — handwheel operation — reduces operating torque for large bore valves	DN150 and above — or any size where manual lever torque is high — standard for pit and buried installations at DN150+
Lever at Extension Top	Lever handle at top of extension — quarter turn open/close — with locking positions	DN50–DN150 where gearbox is not required — insulation extension valves where compact operator is preferred

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Technical Specifications

Parameter	Specification
Valve Body Type	Concentric disc butterfly valve — wafer type (standard) / lug type (dead-end service)
Body Material	CI IS 210 FG260 / DI ASTM A536
Disc Material	SS304 (CF8) / SS316 (CF8M)
Seat Material	EPDM (water, HVAC) / NBR (oil, fuel) / PTFE (chemical, high temp)
Stem / Shaft	SS304 / SS316
Extension Spindle	SS304 / SS316 / MS — specify material at order
Extension Column	MS / GI / SS tube — required for extensions above 500mm
Extension Length	200mm to 3000mm — specify exact length at order — measured on site before ordering
Operator at Extension Top	Lever (DN50–DN150) / Gearbox with handwheel (DN150+ or high torque)
Kerb Box	CI IS 3950 — on request for underground buried valves
Size Range	DN50 (2″) to DN300 (12″)
Pressure Rating	PN10 / PN16
Temperature Range	-10°C to +120°C (EPDM) / -10°C to +150°C (PTFE)
Testing	Hydrostatic shell test / seat leakage test / operator function test
MOQ	10 Nos
HSN Code	84818090

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Applications in Indian Industries

Municipal Water Supply — Underground Distribution Pipelines

CI body SS304 disc EPDM seat gear operated DN150–DN300. Buried zone isolation valves on municipal water distribution networks — valve body buried 0.8m–1.5m below road surface — CI kerb box at surface for T-bar operation by municipality maintenance staff. Furthermore, IS 3950 kerb box standard for Indian municipal water board projects — specify at order stage. Extension column in GI for corrosion protection in buried service.

Building Services — Valve Pit Installations

CI body SS304 disc EPDM seat gear operated DN100–DN200. Main water supply isolation valves installed in underground concrete pits below building entrance or plant room — pit depth 800mm–1500mm — gearbox at extension top for operation from pit access cover level. Consequently, valve maintenance and operation without confined space entry into the pit. Standard for Indian commercial building and hotel basement water supply isolation.

HVAC Chilled Water — Insulated Pipework

CI body SS304 disc EPDM seat lever operated DN50–DN150. Branch isolation valves on insulated chilled water piping in HVAC plant rooms and risers — 50mm–100mm Armaflex insulation — lever extended 100mm–150mm beyond insulation face for manual operation. Moreover, extension prevents insulation cutting and resealing every time the valve is operated for maintenance or commissioning balancing.

HVAC Riser — Fire Insulated Pipework

CI body SS304 disc EPDM seat lever or gear operated DN80–DN200. Fire isolation valves on HVAC riser pipework protected with mineral wool fire insulation in building fire shafts — insulation 75mm–150mm thick — stem extension brings operator above fire insulation face. Furthermore, extension column penetrates insulation cleanly without creating an uninsulated thermal bridge or fire protection gap.

Industrial Underground Pipelines

DI body SS316 disc EPDM seat gear operated DN100–DN300. Buried cooling water, process water, and fire water distribution valves at chemical plants, refineries, and power plants — buried depth 1.0m–2.0m — extension spindle to grade level with surface box. DI body for heavy soil load on large bore buried valves where CI body mechanical strength is insufficient at depth.

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Related Products — Krishna Industries (KELOR)

• Gear Operated Butterfly Valve — standard above-ground gear operated BFV without extension stem — for accessible above-ground installations
• Lever Operated Butterfly Valve — standard lever BFV without extension — for accessible above-ground DN50–DN200
• Electric Actuated Butterfly Valve — for remote operation where manual extended stem is not practical — HVAC BMS integration
• Single Plate Wafer Check Valve (NRV) — install on pump discharge in the same underground and pit-mounted systems
• Double Flanged Butterfly Valve — for large bore underground installations where wafer type between flanges is not suitable and integral flanges are required

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Frequently Asked Questions

1. How do I measure the correct extension length for an underground buried valve?

Measure the depth from the valve centreline (pipeline centreline) to the finished ground surface level. Add 100mm for the kerb box operating nut height above ground. This total is the extension length to specify at order. For example, if the pipeline centreline is 1.0m below ground and the kerb box nut sits 100mm above ground, the extension length is 1,100mm. Always measure on site from the actual pipeline layout drawing — do not estimate from memory. Furthermore, if the depth is uncertain at order stage, round up by 100–200mm — a slightly long extension is manageable on site, but a short extension requires a replacement valve.

2. Can I specify the extension length after ordering?

No — extension length is manufactured into the valve assembly. Therefore, it must be confirmed before order placement. The extension spindle is cut and fitted to the specified length during assembly — it cannot be extended after manufacturing. If the extension length is unknown at order stage, delay the order until the depth is confirmed on site. Krishna Industries can advise on correct extension length if you provide a site sketch or photograph showing the installation depth.

3. What is the difference between an extension spindle and an extension column?

The extension spindle is the rotating SS rod that transmits rotation from the operator at the top down to the valve disc at the bottom. The extension column is a protective MS or GI tube surrounding the spindle — it provides mechanical protection from soil pressure and physical damage and guides the spindle for reliable rotation at depth. For short insulation extensions (under 200mm), spindle only is typically sufficient. For buried and pit extensions above 500mm, both spindle and column are required — the column protects the spindle from soil load bending and ensures reliable long-term operation without binding.

4. What body material should I specify for a buried underground butterfly valve?

Specify ductile iron (DI ASTM A536) for DN150 and above in buried service. DI has significantly higher tensile strength and impact resistance than cast iron — important for resisting soil loads, backfill compaction loads, and traffic loads on buried large bore valves. For DN50–DN100 in buried service, CI IS 210 body is generally adequate. In addition, specify an external fusion-bonded epoxy (FBE) coating or bitumen coating on the body for corrosion protection in buried service — confirm coating requirement at order stage.

5. What is the MOQ?

MOQ is 10 Nos. Municipal water supply and building services project orders — 10 to 200+ Nos across sizes — with hydrostatic test certificate, operator function test, and GST invoice. Specify extension length (mm), operator type (lever or gearbox), disc material (SS304 or SS316), seat material (EPDM or PTFE), and extension spindle material at order stage. WhatsApp installation type (buried / pit / insulated), size list, extension length, and quantity for project pricing within 2 hours.

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Conclusion

Krishna Industries (KELOR) supplies Extended Stem Butterfly Valves for underground buried pipeline isolation, valve pit installations, thermal insulation on chilled water piping, and fire insulation on HVAC risers — CI IS 210 and DI ASTM A536 body — SS304 and SS316 disc — EPDM, NBR, and PTFE seat — gear operated and lever operated — extension spindle and column 200mm to 3000mm — specify exact extension length at order — DN50 to DN300 — PN10 / PN16 — wafer and lug type — GST invoice — Pan India dispatch from Ahmedabad. WhatsApp installation type, size, extension length, and quantity for project pricing within 2 hours.