How to make tube feeder uniform emission from the flat-bottomed silos bulk solids
Most of the world industrial sector should be carried out bulk solids storage and handling. These operations the system plays an important role, and thus they should be
efficient and economical. Powder and bulk solids Branch during transport, accompanied by mixing, blending, grinding, fluidization
And so on.
From the storage structure (silo) nesting often problematic. Powder at the outlet of the silo will Chengke arch or bridge, so that the feed stream is interrupted. Sometimes, the
powder formed in the silo unloader central sulcus. This is called funnel flow silo, the silo of the material stored in the material flow depends on the pressure head. As
If the silo pressure head is insufficient, the material flow deteriorated even stop, so that the material stored in the silo in the central branch grooves becomes bore, usually Telescoping conveyors
called rat hole. Silo generate mouse hole, actually make subsequent job completely stopped, brought the cost is very large.
On the other hand, it may be designed such that the powder hopper on any uniform flow cross section. This flow pattern is called the group stream. Determines the general shape
of material flow angles of the walls of the funnel. If this angle is steeper than the critical value, then the group flow, otherwise, is funnel flow.
Few group flow silo high volumetric efficiency, and the problems are often indiscriminately natural ignorance. Therefore, the industrial sector still seems to want to use a high
volumetric efficiency funnel flow silo. In fact, the highest volumetric efficiency is flat-bottomed silos, but the condition is to be able to completely empty silo. Tube to
Feeder hopper used in conjunction with this, you can receive the best results.
A common illnesses
Most of the required performance stable process, so the system should be designed to meet the above requirements. To powder and bulk solids segregation, for example, joining the
silo, the material will depend particle size distribution. If using central feeding device, the heap will analyze large particles when rolled edge silo
And small are concentrated in the middle. If in this case the use of a funnel flow silo, the discha rge will first of the fine, the rear output and large, the discharged powder
uneven quality of the final product will change. gravity skatewheel conveyor
On the other hand, if the group flow branch positions, then the powder discharged from the silo entire cross-section, so that the segregation of the material remix.
On the silo, especially for group flow branch positions, designed feeder or the exhaust branch equipment is expensive. Because the design of this machine should make the whole
to a feed hopper outlet in order to maintain a uniform activation of the material flow, in this case, the material stored in the silo positive effect on the feed unit.
Naturally, should be designed
Large motor to overcome this peak load. Peak load is caused by the stress distribution in the powder, called the living area or peak stress caused. There are several ways this
can be changed to the arched stress stress zone area. Determine the peak load is not an easy task, in most cases
The motor feeder is designed to give bigger. If the design of the motor is too small, feeder the fault is common.
On the other hand, the powder hopper change form feed stream is also very common. While hordes of silo can design flow, but after the placement of the feeder hopper funnel form
part of the material flow is not necessarily the group flow mode. Powder not start with the front end portion of the discharge hopper funnel, is from the rear
Discharge stream longer group flow. This often results in the formation of rat hole in the warehouse compound, material flow tends to funnel flow. To remedy this situation, we
must consider the feeder hopper and the matching problem, so that the whole system to a whole work. As described below, and tube feeding function in a whole new way
Bulk solid materials to solve problems drag material.
Second, when the silo wall material flow stress
When the bin is full first, then only the discharge, the material flow stress zone created in the cylinder walls. The material flow stress level depends on the size of the
number of material flow patterns and the aspect ratio of the silo. If the material flow patterns slight contraction, the general will stress increases. If the aspect ratio of>
5, the effective transition
Upper part of the deformation energy can follow Jenike theory or group flow hopper design Janssen theory.
Third, the experimental station
Test rig is mounted on a tubular silo feeder. Silo diameter 3.9m, height 1m (if necessary be increased to 3.5m). Tube feeder is located at the bottom of the silo, the captain
1.95m, diameter 0.324m.
A series of pipes called "active device" Slots, Slots flow of material through the tube, the length of these slots to a gradual increase around the silo, which is for the powder
to a uniform cross-section along the flow of the entire silo considered . Tube with screw conveyor used to transport the material hopper
Heart. Located in the bottom center of the silo chute, conveyor belt into the material.
Tube around its own axis only and to be swept at the same time turn the silo. Tube has two drives, one for rotation about its own axis, and one for lateral movement of the
entire section on the bottom of the silo swept rpm. In addition, the screw conveyor has its own drives. Driving
The gear device in the silo center, and drive means itself in the side of the feed chute.
Tubular Division machine to be used in conjunction with axisymmetric silo can well solve many bulk solid materials transported operational problems. Tube feeding function from a
silo or funnel flow trough plane of the carriage of bulk solids.
1 uniform drag material
For bulk solids silos to achieve uniform drag material. Currently, the group is in need of a uniform flow silo drag material that will group flow hopper with belt or screw
feeder, etc. combined and achieve uniform drag material is very difficult, unless the feeder and hopper outlet junction Make the appropriate design, but
This issue silos and tube feeder can be solved with the use.
(2) Minimum segregation
Uniform material also means less drag segregation problem, namely to reduce the powder particle size by separating went to the warehouse wall to avoid the rough and fine focus
on the feed point. With the central segregation in the feeding point is common.
3 crushed less
Because the tube is smooth, while rotating the tube with the surrounding solid material than the dynamic friction screw feeder is small, so transportation is not severe pellets,
4 high energy efficiency
Energy required for transporting bulk solids than the corresponding screw feeder is much less, saving about 70%.
5 rows of uniform quantity
Powder can be stably discharged from the hopper, discharge quantity by changing the rotational speed of the pipe to be controlled. Optimum sweep speed of the tube taken about
the slot geometry Shaanxi; for a given combination of materials and the slot shape, the optimal sweep speed should be constant.