Product configurator

How to select the right butterfly valve — three decisions
Selecting a butterfly valve comes down to three choices that determine performance, service life and compliance. First, match the seat ring to the medium and temperature — this is the most common source of premature failure. Second, choose the connection type based on your pipeline layout and maintenance requirements. Third, decide on manual or automated actuation based on switching frequency and control integration. The sections below walk through each decision. For background on butterfly valve working principles and installation, the Fergo blog covers these topics in depth.
Decision 1 — seat ring by application| Your medium | Recommended seat | Max. temp. | Subcategory |
|---|---|---|---|
| Drinking water, hot water, wastewater | EPDM | +120 °C | DVGW butterfly valves |
| Mineral oil, gas, diesel, greases | NBR | +80 °C | Fergo butterfly valves |
| Solvents, hydrocarbons, aggressive chemicals | FKM (Viton) | +180 °C | Fergo butterfly valves |
| Acids, alkalis, pharma, food | PTFE | +200 °C | PTFE butterfly valves |
| Steam, hot gases, thermal oil | RPTFE / INCONEL 718 | +360 °C | Double eccentric |
Not sure which material suits your medium? Use the resistance check tool to verify compatibility before ordering.
Decision 2 — wafer or lug connection
| Feature | Wafer butterfly valve (AK200) | Lug butterfly valve (AK201) |
|---|---|---|
| Mounting | clamped between two pipeline flanges with through-bolts | bolted to each flange independently via threaded inserts |
| Dead-end service | not suitable — requires flanges on both sides | suitable — can hold pressure on one side while the other is open |
| Pipeline removal | valve drops when one flange is unbolted | valve stays bolted to one flange — downstream pipe removable |
| Weight | lighter (no threaded inserts) | slightly heavier |
| Cost | lower | marginally higher |
| Best for | inline shut-off, HVAC, water treatment | dead-end isolation, tank outlets, maintenance access |
Choose wafer when the valve sits between two permanent flanges and dead-end service is not required. Choose lug when you need to disconnect one side of the pipeline while keeping the other pressurised — for example at tank outlets, filter stations or branch lines.
Decision 3 — manual, pneumatic or electric actuation
Every Fergo butterfly valve carries an ISO 5211 actuator pad for direct quarter-turn actuator mounting. The choice of actuation depends on switching frequency, available energy and control integration.
A hand lever suits infrequent manual operation up to DN150 — it locks the disc in defined positions. A gearbox replaces the lever from DN150 upward for ergonomic high-torque operation. A pneumatic butterfly valve uses a pneumatic quarter-turn actuator for fast switching under 5 seconds — double-acting for process control, single-acting (spring return NC/NO) for fail-safe shut-off. Pneumatic actuation is inherently spark-free and ATEX-suitable. An electric butterfly valve uses a J4C multi-voltage rotary actuator (24 V – 240 V AC/DC) for remote or modulating control via 0–10 V / 4–20 mA — no compressed air required. Fergo assembles every automated butterfly valve in-house — valve, actuator, NAMUR solenoid and limit switch box — tested and shipped ready to install.
Technical data — butterfly valve range
- Nominal size: DN25 to DN1200
- Connection: wafer or lug, PN6/10/16, ANSI Class 150
- Body: ductile iron GGG40/GGG50 (+150 µm epoxy), stainless steel 1.4408, ASTM A216 WCB
- Disc: stainless steel 1.4408, Super-Duplex 1.4469, PTFE-coated, Resicoat R4
- Seat ring: EPDM, NBR, FKM (Viton), PTFE, PTFE+EPDM, RPTFE, INCONEL 718
- Shaft: stainless steel 1.4021/1.4057/F316
- Actuation: hand lever, gearbox, pneumatic (DA/SR), electric (J4C 24–240 V)
- Certifications: DVGW gas (DIN EN 13774), DVGW drinking water, TA Luft, SIL 3, FDA
- Standards:DIN EN 593, ISO 5752, ISO 5211
- Conformity:PED 2014/68/EU
Fergo: Multiple certifications and approvals
Whether you buy a butterfly valve in Germany, Austria, Switzerland, or elsewhere, independent organisations should confirm its suitability. With us, you are always on the safe side. Our products fulfil national and international standards and have the following certifications, among others:
- DVGW Gas (DIN EN 13774): Guarantees the suitability of the valves for use in gas supply systems, compliant with European standards.
- DVGW drinking water: Confirms the safety and hygiene of our industrial butterfly valves for use in drinking water systems.
- TA Luft: Ensures compliance with strict emission limits, ideal for environmentally conscious industrial applications.
- SIL 3: Safety integrity level 3 certified for maximum fail-safety and reliable control in system-relevant installations.
- FDA-compliant: These articles comply with FDA requirements for use in food and pharmaceutical processes.
When to choose a butterfly valve over a ball valve
From DN80 upward, a butterfly valve outperforms a ball valve in weight, space and cost. A DN200 butterfly valve weighs around 15 kg, while an equivalent flanged ball valve weighs over 50 kg. The face-to-face length of a wafer butterfly valve is a fraction of a flanged ball valve at the same DN. Below DN80, or where zero-leakage shut-off and high differential pressure are critical, a ball valve remains the stronger choice. Both types are available with the same pneumatic and electric actuators from Fergo — so switching between them for different pipeline sections is straightforward.
Butterfly valve in stock — 1 136 variants, EU-wide delivery
Fergo stocks 1 136 butterfly valve variants for immediate dispatch across Europe. Standard sizes up to DN600 ship within 2–7 working days via DHL. Sizes DN700 to DN1200 and custom configurations are assembled on request. Each valve ships with datasheet, 3D model download and declaration of conformity. All certificates — DVGW, TA Luft, SIL 3, FDA — are available for download. For deeper technical reading on butterfly valve selection, installation and maintenance, visit the Fergo blog.
FAQ – Your questions, our answers!
Industrial butterfly valves regulate the flow in closed pipe systems. Similar to a gate, a disc inside the valve opens and closes to stop the flow. Their main task is to create one of two states, ‘open’ or ‘closed’, but not to throttle the media. Alternative shut-off valves are designed for this purpose. Our needle valves also allow for very precise control.
The difference lies in how it is fitted to the pipework. A wafer-type butterfly valve is clamped directly between two mating flanges on the pipework without its own flanges and held in place by through bolts – it is compact, lightweight and cost-effective. A flanged butterfly valve (lug design) has its own integral threaded holes at the ends and can be bolted to a flange on one side using stud bolts, allowing for a detachable connection on each side. The lug design is therefore particularly suitable for dead-end service – i.e. wherever one side of the pipeline needs to be isolated from pressure without dismantling the opposite side. Both designs are available from stock at FERGO as part of the Fergo butterfly valve range.
If you want to buy a butterfly valve, guidelines in Germany stipulate a certain performance. From a mechanical point of view, valves today function very similarly. At the centre is a disc that blocks the flow. This is achieved by rotating it transversely to the direction of flow. In a centric design, the pivot point for this is located in the centre. Double eccentric solutions shift this point further along the axis of the pipe and are not aligned with the centre.
The material of the seat ring determines the media resistance and temperature limits of the butterfly valve:
EPDM – For water, hot water, steam, diluted acids and alkalis, as well as media used in water treatment and the food industry. Not suitable for oils. Up to approx. 120 °C.
NBR (nitrile) – For mineral oils, fuels, greases and oil-containing media. Not suitable for hot water or steam. Up to approx. 80 °C.
PTFE – Virtually universal chemical resistance to aggressive acids, alkalis and solvents. The first choice in the chemical and pharmaceutical industries – available as a PTFE butterfly valve.
FKM / Viton® – High resistance to aggressive chemicals, solvents and elevated temperatures up to approx. 180 °C. Ideal for demanding process media.
If you are unsure about media compatibility, the FERGO team will be happy to provide individual advice.
The FERGO butterfly valve range covers a very wide spectrum of nominal sizes and pressure ratings:
Nominal sizes – DN25 to DN1200 (depending on the design; concentric valves up to DN1200, double‑eccentric and DVGW valves up to DN300)
Pressure ratings – PN6, PN10 and PN16 for standard industrial applications; higher pressure ratings (PN25, PN40) for double‑eccentric versions
ANSI/ASME – Class 150 for inch‑standardised piping systems, particularly in the international and American markets
Face‑to‑face length – Wafer type according to ISO 5752 short series; Lug type for dead‑end service
All butterfly valves are available from stock. Use the product configurator to filter specifically by nominal size, pressure rating, seat ring material and body material.
This is generally difficult to answer and depends on the local conditions. As a rule of thumb, you can use the size as a guide: above a certain nominal diameter, we clearly recommend butterfly valves for pipelines. A ball valve, on the other hand, can be ideal for smaller systems. Both types are suitable for flow control and reliably ensure interruptions without leakage. Simply get in touch with us. We will help you find the right product.
That depends on the desired effect. As the name suggests, non-return valves are primarily designed to prevent backflow of media. They operate passively and close automatically when the flow is appropriate. An electric or pneumatic butterfly valve with a drive can also operate automatically, but still switches actively. Depending on the design of your pipes, it may even be worthwhile to use a combination of both valves.
The choice between electric and pneumatic actuation depends on the available energy sources, switching times, and the area of application.
Electric butterfly valves – Ideal for plants without a compressed air supply. Available with 24 V DC/AC, 230 V and 240 V as well as analogue control signals 0–10 V and 4–20 mA for continuous control. Easy integration into PLC, building automation and SCADA systems. Slow to medium switching times (typically 15–60 seconds).
Pneumatic butterfly valves – For plants with an existing compressed air supply. Single-acting (spring-close or spring-open) for safe closing in the event of compressed air failure; double-acting for fast, precisely controlled switching movements. ATEX-compliant versions for hazardous areas. Very fast switching times (under 5 seconds) and robust in harsh industrial environments.
As a rule of thumb: electric for precise control tasks and plants without compressed air – pneumatic for fast switching, high cycle rates and ATEX areas.
Our stainless steel or ductile iron butterfly valves are compact, durable and designed for use in a variety of industries. They are also usually more affordable than comparable gate valves in similar segments. More importantly, however, a butterfly valve that complies with DIN standards performs its task to the utmost satisfaction. The valve blocks the flow reliably and, above all, quickly. The automatic version is particularly impressive.
A double‑eccentric butterfly valve – also known as a high‑performance butterfly valve or double‑offset butterfly valve – differs from a concentric butterfly valve by two geometric offsets of the rotation axis. First, the shaft is offset behind the seat plane, and second, it is shifted laterally from the pipe centre. This causes the disc to immediately swing out of the seat when opening, rather than rubbing against it. The advantages over concentric valves are reduced seat wear, longer service life and the ability to use metal seats. This makes the double‑eccentric design particularly suitable for higher pressures (PN16 to PN40), elevated temperatures, frequent actuation cycles and media that would damage soft elastomer seats – for example steam, hot gases, abrasive media and aggressive chemicals.
DVGW certification is mandatory for gas and drinking water pipes. It ensures that the fitting complies with regulations in terms of both technology and hygiene.
Yes. According to the Drinking Water Ordinance (TrinkwV), all products that come into contact with drinking water must comply with generally accepted technical standards. DVGW certification is proof of this. Without it, you not only risk public health, but also recourse claims.
EPDM is the standard here. It has been tested, is hygienically safe and durable.
For many industrial applications, yes – but not permitted for gas and drinking water. Certification is mandatory in these cases.
These terms often describe similar concepts. The key factor is that in high-quality valves, both the valve disc and the seat ring, and in some cases the interior of the housing, are protected by a thick layer of PTFE. This ensures that all parts that come into contact with the medium are protected against corrosion.
Yes, absolutely. PTFE is FDA-compliant and therefore meets the strict requirements for use in the food and pharmaceutical industries. This guarantees the safety of your manufactured goods.
The continuous operating temperature range of our PTFE butterfly valves is typically between -25°C and +200°C. Some models can also tolerate higher temperatures for short periods.
Of course! Our experienced support team will be happy to advise you individually on housing material, seal type and drive. Simply contact us by telephone or email to find the perfect solution for your application.
Suitable for acids, alkalis, solvents and many oxidising agents, plus high-purity applications in chemical, pharma and food industries. Less suitable for highly abrasive solids/slurries and continuous temperatures above the PTFE limit. Check your medium first in the resistance tool.

















