Butterfly valves are industrial valves for restricting the flow of media such as water, gas or steam in a pipeline. A butterfly valve is closed by turning a disc. Normally the butterfly valve is operated by a hand lever. In the case of large nominal diameters, a gear ratio is required. Pneumatic actuators can be used to automate the butterfly valves. If a pneumatic application is not possible, electric actuators are also possible. Actuators move the centrally mounted valve disc open and closed. Common sealing materials for soft-seated butterfly valves are EPDM, NBR or VITON. The bodies can be made of stainless steel, cast iron and cast steel. Butterfly valves can be supplied with ATEX negative certification, TA-Luft approval and DVGW gas approval, depending on the medium.
Butterfly valves are available in wafer type and lug type. An example for an intermediate flange butterfly valve is the ACI butterfly valve series 22. For butterfly valves with threaded eyes the ACI butterfly valve series 23. The wafer type butterfly valve must be mounted between two flanges. The lug type butterfly valves are equipped with holes to match the flange internal thread. These butterfly valves are suitable for installation at the end of the pipeline without having to install a second flange. Due to the installation without counterflange, this allows easy emptying of the pipelines. Butterfly valves are characterised by their short design. The space required in pipelines is therefore is very small. The low weight of the butterfly valve should also be mentioned. This is especially useful where there are few or no possibilities to intercept the piping. A soft-sealing butterfly valve means that no additional seal is required for installation. Metal-sealing butterfly valves are also possible.
Common sizes for wafer-type butterfly valves and lug type butterfly valves are the nominal sizes DN 25 to DN 600, but large nominal sizes such as DN 1500 are also possible. The hole patterns can be designed to fit flanges to DIN EN 1092-1 or ASME. Possible pressure ratings depend on the design of the butterfly valves and are between PN 6 and PN 100. For high-pressure variants, a stainless steel body with stainless steel disc is generally recommended.
Optional versions such as limit switches for a pneumatically or electrically controlled rotary actuator are also part of our repertoire.
We will be happy to assist you in selecting the right butterfly valve for your process. Contact us for a suitable offer or if you require further information on butterfly valves.