HomeIndustriesWater Treatment & WastewaterButterfly Valves
Water Treatment & Wastewater×Butterfly Valves

Butterfly Valves for Water Treatment & Wastewater

Butterfly valves are the dominant isolation and throttling valve for water treatment, water distribution, and wastewater treatment plants — their large bore capability (to DN1200), low pressure drop, and low cost at large bore make them the natural choice. Vajra Industrial Solutions supplies ductile iron and SS 316 butterfly valves with EPDM, NBR, or PTFE seats for potable water, filtered effluent, sludge, and chemical dosing service in water treatment plants.

Get a QuoteBrowse Butterfly Valves →

Key Applications — Butterfly Valves in Water Treatment & Wastewater

Raw Water Intake and Filtration

Large bore butterfly valves (DN300–DN1200) for raw water intake screens, gravity filters, and media filter inlet/outlet isolation. Ductile iron body with EPDM seat and SS 316 disc. Gear actuator or electric actuator for remote operation from SCADA system. Potable water approval (WRAS, NSF 61) required.

DN300–DN1200, PN 10–16, Ductile Iron / SS 316 disc, EPDM seat, WRAS, AWWA C504

Pump Station Discharge and Pressure Mains

Lug-type butterfly valves for pump station discharge isolation. Electric or pneumatic actuator with fail-safe close on power failure. Anti-water hammer closure rate (time delay on close). DN150–DN600 for distribution mains, DN600–DN1200 for transmission mains. Buried service versions with extension stem and surface box.

DN150–DN600, PN 16–25, Ductile Iron, EPDM, electric actuator, BS 5155

Wastewater and Sludge Handling

Rubber-lined butterfly valves for raw sewage, primary sludge (2–8% solids), and digested sludge handling. EPDM or NBR rubber-lined body for solids resistance. Higher torque actuator required for sludge due to increased viscosity. Knife gate valves used for thickened sludge (>8% solids) where butterfly valve disc can foul.

DN100–DN600, PN 6–16, Ductile Iron, NBR full-rubber lining, electric actuator

Chemical Dosing Systems

Small bore (DN15–DN100) SS 316L or PVDF butterfly valves for chemical dosing and feed lines (chlorine, alum, ferric chloride, lime slurry). PTFE-lined for oxidising chemicals (sodium hypochlorite, chlorine dioxide). Pneumatic actuated for automated dosing sequence control.

DN15–DN100, PN 10–16, SS 316L / PVDF, PTFE lined, pneumatic actuator

Potable Water Distribution

Butterfly valves for potable water trunk mains and distribution networks. Must carry WRAS (Water Regulations Advisory Scheme) approval for UK service or NSF/ANSI 61 for USA. Lead-free materials required for potable service. Ductile iron with NSF 61-compliant epoxy coating internally. Full-bore design for minimal pressure drop in distribution.

DN100–DN900, PN 16, Ductile Iron, NSF 61 / WRAS, EPDM, gear operator

Required Certifications

WRAS (Water Regulations Advisory Scheme) — UK potable waterNSF/ANSI 61 — USA potable water contact materialsEN 593 — Industrial butterfly valves (European standard)BS 5155 — Specification for butterfly valves (UK)AWWA C504 / C516 — American Water Works Association (USA water service)API 609 — Petroleum industry butterfly valves (if also used in process)ISO 9001:2015 — Quality management system

Recommended Materials

Ductile Iron GGG-40 / GGG-50 — standard water and wastewater body
SS 316 disc — standard for all water service (corrosion resistance over cast iron disc)
EPDM seat — standard potable water and wastewater service
NBR seat — oil-contaminated water, lubricants, mild hydrocarbons
PTFE seat — chemical dosing, oxidising agents, high purity service
SS 316L body (small bore) — chemical dosing and corrosive water (seawater, brackish)
Epoxy-coated interior (ductile iron) — potable water corrosion protection

Selection Factors

Bore and flow: Large bore (DN300+) butterfly valve is 40–70% cheaper than equivalent ball or gate valve
Mounting: Wafer (in-line), lug (end-of-line or pump isolation), or double-flanged (high pressure, high torque)
Seat material: EPDM (water service); NBR (slight hydrocarbon contamination); PTFE (chemicals, high temperature)
Pressure class: PN 10–16 for most water service; PN 25 for high-head pump stations
Potable: WRAS or NSF 61 certification required for drinking water systems
Actuation: Manual gear for infrequent operation; electric actuator for remote SCADA control; pneumatic for fast-acting applications

Technical FAQs

Do butterfly valves need potable water certification?
Yes — for any application where the butterfly valve contacts drinking water intended for human consumption, certification is required. In the UK, valves must carry WRAS (Water Regulations Advisory Scheme) approval. In the USA, NSF/ANSI 61 certification is required for materials in contact with potable water. EPDM seats, epoxy coatings, and SS 316 discs all need to be certified to the applicable standard. Vajra can supply WRAS and NSF 61 certified butterfly valves for potable water service.
Can butterfly valves handle sewage sludge?
Standard butterfly valves with elastomeric seats handle primary sludge (2–6% solids) and digested sludge (3–5% solids) adequately. For thickened sludge above 8% solids, or for dewatered sludge cake, knife gate valves are the preferred solution — the knife-edge gate cuts through fibrous and thickened material that would prevent a butterfly valve disc from seating cleanly. Always specify NBR or full-rubber-lined (FRL) seats for sewage sludge service.

Other Water Treatment & Wastewater Valve Guides

Gate Valves for Water & Wastewater

Read guide

Check Valves for Water & Wastewater

Read guide

Ball Valves for Water & Wastewater

Read guide

Globe Valves for Water & Wastewater Treatment

Read guide

Butterfly Valves in Other Industries

Butterfly Valves for Oil & Gas

Read guide

Butterfly Valves for Chemical Processing

Read guide

Butterfly Valves for Power Generation

Read guide

Butterfly Valves for Food & Beverage

Read guide

Butterfly Valves for Pharmaceutical

Read guide

Butterfly Valves for Mining & Minerals

Read guide

Butterfly Valves for HVAC & Building

Read guide

Butterfly Valves for Pulp & Paper

Read guide

Butterfly Valves for Marine & Offshore

Read guide

Butterfly Valves for LNG & Cryogenic

Read guide

Get a Quote

Butterfly Valves for Water Treatment & Wastewater

Share your process conditions or valve specification — we'll respond with pricing and compliance confirmation within 24 hours.

Request a QuoteWhatsApp for Quick Quotesales@vajravyuh.com

Browse Products

All Butterfly ValvesWafer Type Butterfly ValveLug Type Butterfly ValveDouble Flanged Butterfly ValveTriple Offset Butterfly Valve

Water Treatment & Wastewater Industry

Water & Wastewater Valve Overview

All Industries

Oil & GasPowerChemical & PharmaWater TreatmentCement & MiningHVACManufacturingEPC