Fox Valve is the leading global supplier of venturi
eductors and venturi transport systems for pneumatic
conveying of powders, pellets, and bulk solids. They
enable the use of low pressure air ( below 14 psig or
1 bar) to be used to move powders, pellets, and bulk
solids with no moving parts. Fox has sold venturi eductors
continuously since our first sale, in 1963, of a stainless
eductor for use in transporting plastic pellets with
air at 4 psig.
- No Maintenance
- No Blow-Back
- Minimal Product Degradation
Fox Venturi Eductors - What are they?
Fox Venturi Eductors convert the output of a blower
into suction that can be used to entrain and feed powders,
pellets, and bulk solids into a pneumatic conveying
system. Because they have no moving parts, they can
operate almost entirely maintenance-free.
The eductor acts to compress the air/solids mixture
to a pressure adequate to overcome losses in the downstream
convey line. The eductor has three connections:
- Motive Air
- Suction or Product Inlet
How are they used in pneumatic conveying systems?
Fox Venturi Eductors are used to feed bulk solids,
such as powders, pellets, flakes, and particulates,
into positive, dilute-phase conveying systems. They
are commonly used in place of rotary valves where airlocks
simply cannot perform adequately.
For detailed information on eductors - Download Bulletin
301 or request that we mail you a full color, hard copy
of Bulletin 301.
Why are eductors used in pneumatic conveying
- Fox Venturi Eductors have No Moving Parts - allowing
for maintenance-free feeding of bulk solids. In applications
involving fine, abrasive, or irregularly-shaped products,
this is an enormous advantage. Replacement of existing
rotary airlocks with venturi eductors makes for simpler,
more reliable conveying systems. Designing with eductors
from the beginning ensures the most reliable product
- No Blowback - All rotary airlocks have blowback.
If the product conveyed is fine or abrasive, blowback
can cause extreme wear problems. Even with free-flowing
products, blowback can be a problem, causing bridging
and housekeeping problems, or even an explosion hazard.
When installed beneath baghouses, screw conveyors,
or dust collectors, airlocks can be a major source
of fugitive dust emissions, which are eliminated after
a retrofit to Fox eductors.
- No mechanical shearing - Eductors minimize the
shearing, smearing or degradation of product common
with rotary airlocks. And, of course, safety is simply
not a concern with Fox eductors.
How are they designed? How are they tested?
Are they guaranteed to work?
Fox's eductor designs have been exhaustively tested
with different materials, line lengths, motive air flows
and pressures - yielding the most complete set of performance
data ever accumulated. This data has been transformed
into computer algorithms which allow our engineers to
rapidly and precisely predict eductor performance with
almost any product in your system. Moreover, we have
over thirty years of hands-on industrial experience
and feedback to draw upon. This enables Fox to performance
guarantee every quotation and every eductor that leaves
our factory. New or challenging materials can be tested,
if necessary, in our in-house conveying test rig. Interested
parties are always welcome to visit and witness tests.