Ductile Iron Electric Butterfly Valve

Size 50mm to 600mm
Body FBE Coated Ductile Iron
Seat EPDM
Disc 316 Stainless Steel
Pressure Up to 16 BAR (depending upon size)
Actuation Electric

• What is an Electric Wafer Butterfly Valve?

  An electric wafer butterfly valve is a butterfly valve that is designed to clamp between two flanges without the need for the bolts to go through threaded holes on the body of the butterfly valve. It has a direct mounted IP67 electric actuator fixed to the valve which conducts its 90 degree turn (open/close). The valve body sits like a 'wafer' between the flanges and therefore fit multiple flange standards unlike lugged which will be designed to fit only one standard. In this case we are talking about ductile iron (similar to cast iron but better advantages in terms of strength, elongation & life) center line wafer butterfly valves. The center line refers to the location of the disc and shaft in relation to the body (there are other kinds of butterfly valves such as double & triple offset) where it is precisely in the middle. These valves can have different seat materials but the most common would be EPDM but others such as FKM, NBR or PTFE are also used. The actuator comes with extra limit switches for voltage free end of stroke open/close feedback and a visual indicator.

• How does an Electric Wafer Butterfly Valve work?

  A butterfly valve works by the shaft rotating 90 degrees which will take the position of the disc in the flow from open to close (or vice versa). When it is closed a seal will be formed between the disc and the seat effectively stopping the flow of the media. When it is opened again the disc comes away from the seat and when it is fully open sits side (smallest surface area facing) on to the direction of the upstream flow. This 90 degree turn is conducted by an electric actuator which is connected to a shaft which in turn is mated to the disc by a spline. When the actuator is operated by an external relay the shaft will be rotated effectively turning the disc, switching it to its other state (either open or close). It will take anywhere from 8 to 20 seconds for a cycle depending upon the actuator size (it generally gets longer as the actuator size increases with required torque). Once it rotates its required 90 degrees a microswitch on a cam is triggered and power to the motor is shut off. It will then wait for the relay to be switched and the valve will do the same thing in the other direction.

• How long will my Electric Wafer Butterfly Valve last?

  Like any valve this depends upon the usage case of your butterfly valve, its environment, media and how many times it is cycled. For instance if it is on a clean wet media, in a clean environment and not cycled regularly the life will be decades. If it is on a corrosive media and in a dry application with a high cycle rate the life will be much shorter. We conduct regular lab testing and 6,000 cycles is a reasonable life cycle depending upon the application. One advantage of this design is that the seat is replaceable and available as a repair kit. The actuator's life will depend upon how clean the environment is, its correct installation, its duty cycle and electrical supply. Being CE certified they have been tested to 6,000 life cycles for general purpose applications but can last much longer. One common mistake we see is an incorrectly rated cable gland being installed. Our actuators are IP67 which gives you great water ingress protection but it will only be as good as the cable gland installation. You need to bear in mind the duty cycle of the actuator model you are using and do not exceed that eg. (if it is 75% you can use the actuator for 75 seconds with a 25 second down time out of 100 seconds). If you do it can lead to premature failure of the actuator.

• How do I install an Electric Wafer Butterfly Valve?

  These wafer butterfly valves are designed to clamp between two flanges. The bolts will pass through from one flange to the other to give the clamping force on the valve and keep it in position. The seat of the valve also forms the gasket on the flanges so there is no need for a secondary gasket. The bolts should be tightened in a diagonal shape to avoid over tightening in one area. For a full list of instructions please visit our butterfly valve installation & maintenance guide. The electric actuator must be wired in accordance with the wiring diagram which is on the front of the actuator and also inside the housing. This varies between models and voltages so if there is any doubt please consult us.

• What are typical uses of an Electric Wafer Butterfly Valve?

  These are very common in the water industry especially because most of our models hold a Watermark and Standards mark approval. They are also used for general purpose applications as long as the media, temperature and pressure are compatible. As it has an electric actuator it is usually used in applications where a reliable air source is not present (as it is cheaper and faster to use a pneumatically actuated ball valve). Also if the actuator loses power it will fail in the position it is in (even if it is part way through a cycle eg. half open etc) so they are not used in fail safe applications. Here a spring return pneumatic or spring return electric actuator would be used (spring return electric is expensive).

• How long will my product take to get to me? 

  This depends upon where you are based and the freight method chosen. If the express freight option is selected it is usually next day delivery to metropolitan areas in Australia for under 5kg. If free freight has been selected it will go by road freight which can be anywhere from 1 to 10 days depending upon your location. It usually averages 3 days.

• What warranty do I get?

  All of our products come standard with a 12 month warranty. The good news is we have very strict quality controls and all valves leave our warehouse tested (full material and testing certificates to API 598 are available) and inspected so there are rarely any issues. Also once your valve is in and operating it will most likely continue to do so for a very long time.