Fox eductor systems have been used for over twenty years to replace belts, bucket elevators, and fork lift traffic, automating the handling of fragile products that many once thought were not capable of being conveyed pneumatically.

The Five Steps to Conveying Fragile Products at Your Plant:

Step 1: Eliminate Airlocks
Rotary valves (airlocks) are simply not suitable for conveying fragile materials. As the rotor sweeps across the product inlet, the inevitable shearing of particulates creates broken pieces and fines. Pneumatic conveying of fragile particulates can rarely be accomplished without the elimination of moving parts.

Step 2: Testing at Fox Valve's Test Facility
There are no theoretical models to predict whether a glass ball, coffee bean, or raisin can be conveyed without damage. Fox has run hundreds of conveying trials at our test lab, which has proven extremely reliable at predicting whether your product can or cannot be conveyed without damage. If the tests are successful, Fox can ascertain what minimum transport velocity is suitable for your product. Customers are always welcome to witness these trials. Our facility is 45 minutes from Newark Airport (EWR.)

Step 3: Limit Conveying Velocity
Minimizing transport velocity is the single most important factor in successfully transporting friable materials. Unlike airlocks, an eductor always rigidly controls how much air enters the transport system from the blower via the motive nozzle orifice. By carefully sizing this orifice, Fox can engineer into our equipment an upper limit on how much air enters the system‹ therefore limiting downstream conveying velocity.

Step 4: Proper Blower Selection
Quiet, maintenance-free Rotron blowers are usually supplied, facilitating a compact installation with a very small footprint. Rotron blowers can be used to drive systems with 1" to 6" convey lines. Fox will, of course, integrate positive displacement blowers into our solution if dictated by throughput or conveying distance.

Step 5: Field Adjustable Equipment: Letting the User Assert Control over Transport Velocity:
Inclusion of the Fox Bleed Valve Assembly
Lab testing is one thing; actual production is something else. And will the product Fox tested last year be the same product you're making next year? Fox conveying systems for fragile products usually include an elegantly simple means for you or your operators to adjust, reduce, or control product transport velocity. The bleed valve assembly permits you to vent off, through a silencer, a portion of the blower output. This enables you to respond to changing conditions in your process and use the highly flexible Fox system to deliver a transport velocity that you can control. If a different product requires lower velocities, you can bleed off more air to convey more slowly. If another product is denser and less prone to damage, you can reduce the bleed and convey at higher velocities with a higher throughput.

Many of our Case Studies illustrate important advantages of conveying fragile products with Fox eductors:

• Snack Foods, Convey without degradation Case Study #63
• Whole Coffee Beans, Convey from bulk bags Case Study #56
• Puffed rice, Convey without degradation Case Study #55
• Pet food, Convey from packing area Case Study #42
• Chewing gum sticks, Case Study #26
• Plastic pellets, eliminate angelhair Case Study #04