Dual-Flap Explosion Isolation Valve

Fike DFI is a compact, lightweight dual-flap explosion isolation valve which prevents an explosion from propagating upstream into connected equipment.

Here's How It Works

1. Dual flaps are held open by normal process flow.

2. Deflagration pressure reverses the flow and closes the flaps.

3. The locked flaps protect upstream equipment.

Activated by the pressure itself

DFI is considered a “passive” explosion isolation valve because it is activated by the pressure itself and not activated with electronics. Therefore, DFI is commonly paired with other passive devices such as Fike explosion vent panels to provide cost-effective, comprehensive explosion protection on the dusty air intake lines of various applications including dust collectors, cyclones, conveyance systems and more.

Fike DFI has sizes up to 40 inches (DN1000), making it ideal for even larger dust collectors or other industrial applications that horizontally convey organic dust.


Fike DFI is an “explosion isolation valve you can trust” because of its:

Flexible Installation

1. Flexible Installation

Engineered to perform reliably in both horizontal and vertical pipes and close to bends, depending on DFI size. May also be installed closer to a vessel than most other flap valves due to its compact, fast-closing flaps.

Metal Dust Piles

2. Wide Application Range

Withstands high explosion pressures up to 1.5 barg from most dust hazards, including from common organic dusts, light metal dusts and low MIE (minimum ignition energy) dusts.

DFI Stainless Steel (373x250)

3. Stainless Steel Option

Safe for use within food production and chemical plants to protect against rust, paint or other contaminants from entering the product. Available in sizes 4-32 inches (DN100-800).

DFI Real World Testing_20

4. Real-World Testing

Exceeds testing standard EN16447 by simulating conditions it will experience in the field to ensure it will reliably work when called upon. Fike testing proved this to not be true for all other flap valves currently on the market.

» Download Are Flap Valves Safe White Paper

DFI Flexible Installation

“Because it is designed for installation in both vertical and horizontal orientations and protects against a wide range of combustible dust hazards, Fike DFI is suitable for most industrial applications when passive isolation explosion protection is achievable,” said Jim Vingerhoets, Fike Explosion Safety Consultant | Europe.

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