Butterfly Valves
Butterfly valves can be used to control certain media in a pipeline. In this type of industrial valve, the fluid flow is changed by means of a rotatable disc (disc). Smaller nominal sizes are operated by hand lever. Larger nominal diameters with gearbox and handwheel. Furthermore, we can also offer the valves by electric actuator, pneumatic actuator or hydraulic actuator.
Butterfly valves from the specialist
A advantage of this type of valve is that the medium in the pipeline can be throttled. Due to the special type of construction, the valve also saves a lot of space. The Valve can be used for high temperatures.
This type of butterfly valve is in metallic sealing design.
Due to the short design, butterfly valves have a lower weight than a comparable gate valve. Butterfly valves offer many advantages. The streamlined design and easy installation in a pipeline make the butterfly valve a versatile all-rounder.
Centric, eccentric, double or triple eccentric design.
Constitutively one distinguishes butterfly valves between eccentric and centric. Centric means when the disc rotates 90 degrees around its axis perpendicular to the flow direction of the medium. The pivot sits in the middle of the flap seat, and thus in the center of the pipeline. Centric designs are generally available with soft sealing liners and are unsuitable for higher temperatures. By contrast, double-eccentric butterfly valves are also suitable for particularly high temperatures because the seat ring is metallic. This represents a clear advantage over the central butterfly valve. A further advantage is the usability even at high pressure in the pipeline, since centric valves are usually suitable only up to 16 bar.
Construction at a glance
✓ Centric flange adapter also called wafer-type. This design is only suitable for clamping in a line. This type of flap is suitable for both gaseous and liquid media. Can be used to control as well as to close or open the pipeline.
✓ Flange Butterfly valve also called Lug-type. The housing of this design has integrated threaded holes. As a result, a simple screwing and unscrewing the flap is made possible to a pipeline.
All housing types can be manufactured with flange connections according to DIN or ANSI standard. Pressure losses are significantly lower with butterfly valves than with other industrial valves such as shut-off valves. In valves, a higher-pressure loss is given by a kind of deflection of the fluid flow. Thus, butterfly valves work much more efficiently than valves.
Sealing element of the butterfly valve
The sealing element, also called seat is one of the most important elements on a butterfly valve. Sealing elements ensure tightness in the pipeline. There are also different materials for diverse customer requirements.
✓ NBR (nitrile butadiene rubber). The rubber material has a high resistance to mineral oils, fats, water, oils or hydrocarbons.
✓EPDM (ethylene-propylene-diene). This rubber material has good resistance to heat, hot water or chemicals.
✓ VITON This elastomer has high thermal and chemical resistance and is therefore suitable for oils, chemicals or other higher temperature media.
✓ METAL SEATED Almost suitable for all common media. Can be used up to more than 500 degrees.