Name: Pneumatic Butterfly Valve Wafer Type
Brand: Supreme Valves India
SKU: pneumatic-butterfly-valve-wafer
Availability: InStock
Rating: 4.8 (82 reviews)

Question 1

What is the difference between wafer and lug-type pneumatic butterfly valves?

Accepted Answer

Wafer valves are held between pipeline flanges by bolts that pass through the valve body - they cannot stand alone and require flanges on both sides. Lug valves have threaded inserts on the body that allow them to be bolted to a single flange and stand alone in the pipeline (useful for dead-end service). For general on/off service with flow in both directions, wafer valves are more cost-effective. For applications requiring the valve to seal one end of the pipe (tank isolation, dead-end service), lug valves are mandatory.

Question 2

What is the pressure rating of pneumatic wafer butterfly valves?

Accepted Answer

Standard wafer butterfly valves are rated ASME Class 150 (PN10/PN16 depending on size), suitable for working pressures up to 285 PSI at ambient temperature. Larger valves (above 12-inch) may be rated lower. For higher pressures, special designs or double-flanged valves are required. Always check the pressure-temperature rating chart for your specific liner material - EPDM ratings decrease significantly above 120 deg C.

Question 3

Can pneumatic butterfly valves be used for throttling (partial opening)?

Accepted Answer

Yes, pneumatic butterfly valves can be used for throttling, but with caveats. The flow characteristic of a butterfly valve is generally quick-opening, meaning a small stem rotation produces a large change in flow. For precise throttling, consider: selecting a charactered disc (offset disc design) for improved controllability; using a positioner on the pneumatic actuator for precise setpoint control; and ensuring the valve is sized so the operating point is in the 30-70% open range where control is best. For critical throttling, a globe valve may be a better choice.

Question 4

What liner material should I select for my butterfly valve?

Accepted Answer

Liner selection depends on media and temperature: EPDM (Ethylene Propylene) is best for water, dilute acids/alkalis, and food service - not compatible with petroleum oils. NBR (Nitrile) is designed for petroleum products, hydraulic oils, and fuel service - not for ketones or esters. PTFE is chemically inert for aggressive acids/alkalis but has lower pressure ratings and higher cost. Always verify chemical compatibility with the liner material before ordering.

Question 5

How do pneumatic butterfly valves compare to pneumatic ball valves?

Accepted Answer

Butterfly valves are generally lower cost and lighter weight than ball valves, especially in sizes above 6-inch. Butterfly valves require less torque to operate at high pressure because the disc rotates through the flow path (not against it), making them more efficient. However, ball valves provide tighter shut-off (bubble-tight vs. slight seepage for butterfly) and are better for on/off service. Butterfly valves are preferred for large water lines, HVAC, and throttling; ball valves for process shut-off and critical service.

Question 6

What are common applications for pneumatic wafer butterfly valves in India?

Accepted Answer

In India, pneumatic wafer butterfly valves are extensively used in: water distribution and HVAC systems in commercial buildings; effluent treatment plants in Gujarat and Tamil Nadu industrial zones; cooling water circuits in power plants; chemical process lines in pharmaceutical and textile manufacturing; fire protection systems; and marine ballast water management. Their compact wafer design makes them ideal for retrofitting in existing pipeline systems.

Component	Material Specification
Body & Bonnet	Ductile Iron (ASTM A536 / EN-GJS-400-15)
Stem / Spindle	SS 410 / SS 420
Seat / Trim	EPDM / NBR / Bronze

Parameter	Specification / Standard
Manufacturing / Design Standard	EN 1171 / AWWA C509 / BS 5163
Testing Standard	API 598 / EN 12266-1
Pressure Rating	PN16 / PN25

S.N.	Parts Name	Material
01	BODY	WCB ,CF8 ,CF8M
02	DISC	WCB ,CF8 ,CF8M
03	MOULDED SEAT	EPDM , PTFE , NBR , VITON
04	STEM	AISI 410 , AISI 316 , AISI 304
05	LEVER	M.S , S.S

Inch	MM	A	ØD	H1	H2	ØE	ØM	N	PCD
1.1/2"	40	40	80	54.0	120.0	40	15.9	4	98.5
2"	50	43	95	68.0	130.0	50	19.1	4	120.5
2.1/2"	65	46	108	77.0	138.0	65	19.1	4	140.0
3"	80	46	124	84.0	157.0	80	19.1	4	152.4
4"	100	52	150	105.0	170.0	100	19.1	8	190.5
5"	125	56	186	120.0	186.0	125	22.2	8	216.0
6"	150	56	205	135.0	200.0	150	22.2	8	241.0
8"	200	60	258	183.0	237.0	200	22.2	8	298.4
10"	250	68	321	223.0	286.0	250	25.4	12	362.0
12"	300	78	368	255.0	314.0	300	25.4	12	431.8
14"	350	78	438	280.0	340.0	350	28.6	12	476.2
16"	400	102	490	310.0	378.0	400	28.6	16	539.8
18"	450	114	602	350.0	400.0	450	31.8	16	577.8
20"	500	127	700	380.0	440.0	500	31.8	20	635.0
24"	600	154	695	448.0	510.0	600	34.9	20	749.3

Pneumatic Wafer Butterfly Valve | Lug & Wafer Type

Key Specifications

Materials of Construction (MOC)

Technical Specifications

Material of Construction

Testing Details & Standards

Dimension Tables