SPECIAL FEATURE


THINGS TO CONSIDER:


• Rotary plug diverter made from cast is costly to purchase, install and to maintain.


• Packing of powders between the rotating plug and external housing can cause the plug style diverter to bind.


• Blower should be shut down before shifting ports on a rotary plug diverter, as the actuation will block the conveying line causing system back pressure.


2. Flapper Style Diverters A flapper style diverter uses a


metal flapper that shifts to block one port and divert material and air to the open port. In some models, the flapper seals against a replaceable polyurethane liner. In other models, polyurethane is sandwiched between two metal plates to create a better seal.


BENEFITS:


• Material can be diverted during a stream because both ports are not blocked during the shift.


• Diverter is lightweight, therefore easier and safer to install.


• Valve is inexpensive to purchase and to replace parts.


THINGS TO CONSIDER:


• Flapper seals are exposed to material abrasion requiring seal replacement often.


• Air and fine material leak past worn seals into the closed conveying line resulting in system pressure drops, cross-contamination, and potential line plugs.


• Flapper loses its seal under high vacuum as the flap is “lifted” from the internal sealing surface.


3. Sliding Blade Diverters The sliding blade diverter is fabricated


with an “orifice” machined in the blade, which slides between two hard polymer seal plates. Upon shifting, the orifice aligns with the conveying line selected, while the


3. Sliding Blade Diverters sliding plate blocks the opposite port.


BENEFITS: • Material can be diverted during a stream without the need to shut down system blowers or fans.


• Diverter is lightweight and can be maintained without removing it from the conveying line.


• Design allows for a wide variety of configurations to match unique piping patterns.


THINGS TO CONSIDER:


• Valve limited to dilute phase pneumatic conveying.


• Transition from inlet to outlet creates slight pressure drop.


• Residual amount of material may not purge when shifting of ports resulting in cross contamination.


4. Flexible Tube Diverters A flexible tube or hose style diverter


uses the basic sliding orifice blade design. A tube stub is welded to an orifice style blade, and a flexible hose is then attached to the tube stub. As the diverter blade is shifted, the conveying line, a flexible hose, moves from one port to the other.


BENEFITS:


• Very little pressure drop across a flex tube diverter.


• Purging the conveying line prior to shifting the diverter eliminates material cross contamination.


4. Flexible Tube Diverters


• Material can be diverted during a stream without the need to shut down system blowers or fans.


THINGS TO CONSIDER:


• Severely abrasive applications will wear out the hose quickly.


• Overall stack up height and hose support requires large “footprint”.


• Exposed pinch points create a safety hazard if the hose is not totally encased.


Conclusion Many types of 2-way diverter designs


are available to handle a wide range of materials and application-specific requirements. No diverter can fit all applications, so it is important to do adequate research and check with multiple suppliers before you select which diverter is right for your pneumatic conveying system. www.vortexvalves.com


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