Designing New Systems with Venturi Eductors:
As with any conveying system, the three basic questions are: What product? How much? How far? Send us a completed data sheet and Fox engineers will prepare a Performance-Guaranteed quotation on an eductor or a complete conveying system. The quotation will include all relevant operating data.

Limitations:

• For Rates up to 15-20,000 lb/hr
• For Distances up to 300 ft

Fox Venturi Eductors can convey most dry bulk solids, but the following conditions must be met:

• Solids must be gravity fed into the eductor.
• Downstream piping can never be reduced.
• Eductors can never be used in series. All elbows should be wide-radius. Flex hose lengths must beunder 5 - 10 ft.
• Conveying line length must be below 400 ft.
• Adequate venting/dust collection at destination.
• Eductors are almost never used for truck, barge, or railcar unloading.

A Single positive displacement blower is used to drive three 2" Fox Eductors located beneath a three-cell collector at foundry.

Fox Eductors for Rotary Valve Venting
Fox Rotary Valve Venting Eductors enable a retrofit of badly leaking rotary airlocks that cannot be replaced by eductors. Retrofit with venting eductors can eliminate blowback, reduce required maintenance, and can increase - sometimes significantly - throughput from existing rotary valves. Ask for Bulletin 360

Retrofitting Existing Equipment

Retrofitting existing systems with Fox eductors can result in very significant improvements. These may include:

• Eliminate airlock wear
• Reduce product damage/degradation
• Avoid dust emissions and leakage
• Facilitate clean-outs if cross-
   contamination is critical
• Reclaim otherwise discarded product

Please note that retrofitting existing pneumatic conveying systems with eductors can have some technical and commercial challenges:

• Technical - Airlocks may experience wear and excessive blowback when the downstream convey line and/or blower is undersized for the given application. A simple replacement of the airlock with an eductor in this circumstance in possible, but unlikely.
• Commercial - In order to successfully retrofit an existing system, Fox would need to analyze and understand the existing blower, existing pipe geometry, existing dust collection, characterize the material to be conveyed and understand the rate requirement. Fox cannot then guarantee the operation of the entire system if our Scope of Supply is limited to just a replacement venturi eductor.

Retrofitting Dust Collectors and Baghouses with Fox Eductors
Eductors are frequently installed beneath dust collectors, often replacing screw conveyors which collect dust from multiple outlets. Screw conveyors are primary sources of fugitive dust , often need repair, and require that all modules of a baghouse are shut down if one outlet is clogged or need repair. Multiple eductors enable all outlets to operate while one is accessed for maintenance.

Multiple Eductors Driven by One Blower: Eductor systems often use one blower to drive many eductors, making for surprisingly simple systems when handling material from multiple outlets, as is common with dust collectors.