In the pneumatic transport system, the main equipment is the down silo pump pneumatic
transport plant; the performance can completely reflect nowadays pneumatic
transport technology. The silo pump is featured in simple, compact and reasonable
configuration, to adopt PLC to realize the automate control, it is features as
follows:

Mechanical parts 
Thanks to the venturi ring-form air supplementary apparatus, which helps a lot for
form more harmonious, more smooth conveying. The conveying pressure is low than
0.25MPa.

Electric control part 
Control mode: modular PLC is applied, PLC is procured from Germany SIEMENS Company,
which could be replaced or expanded easily, and sufficient space has been reserved
for modification and supplement. Liquid water of Interface device by the product
of Germany Siemens Company will be applied, which not only is easy to operate,
but also profit the environment. 

Operation mode: 
Operation mode could be switched between auto-operation and manual-operation. For
auto-operation, only "start" button should be pressed, then the system will come
into normal operation procedure automatically, all the work conditions will be
reflected on the operational panel. Manual operation could be performed on the
spot. Auto-control and manual-control will be interlocked. 

Control system 
For the conveying system, there installed monitoring instruments, warning display
and protection measures to supervise/control. The pressure of compressed air,
main valves, motors, and pressure along conveying pipe by receiving and sending
signals to the control system. For some other objects, which have no reactive signals,
all the control will be realized by logical programmer. Malfunctions and failures
will be displayed on the panel, accompanied by sound warning. 

Conveyor will shift automatically to manual operation when failure occurs to be
convenient for servicing and without affect the normal operation of the system.
In order to prevent blocking of conveying material, post-purging procedure will
be done just before the conveying is about to end. During the normal operation
of the system, if blocking trend is detected, then the logical programmer will be
shifted to safeguard process from subroutine immediately to mitigate the blocking.

If power supply for the system is cut by accident, when re-electrified, the system
could ensure all executive objects are in stand by status, which could prevent
to start the system by accident.