The diameter of the powder conveying pipe should not be too large, as it is not conducive to forming a stable material column. Generally, the diameter does not exceed 100mm, and the commonly used diameter is between 38-75mm. Especially for loose powder, it is difficult to form a material column with a large diameter. The inner wall of the pipeline should not be raised, and it is required to be smooth with low friction coefficient, so thin-walled seamless steel pipes are generally used.

輸送管道的布置

Layout of conveying pipelines

管路布置好采用傾斜和水平形式，因為垂直管道中上面的料柱易落下與下面的料柱合并而產生堵塞，在布置空間允許的情況下彎管愈少愈好，彎管曲率半徑不能太小，至少R/D>10，兩個彎管之間也不能太接近，要做到料柱的移動在離開一個彎管前不受下游另一個彎管的阻礙。

The pipeline layout should be inclined and horizontal, as the upper material column in the vertical pipeline is prone to falling and merging with the lower material column, resulting in blockage. If the layout space allows, it is better to have fewer bends. The curvature radius of the bend should not be too small, at least R/D>10, and the two bends should not be too close. It is necessary to ensure that the movement of the material column is not hindered by another bend downstream before leaving one bend.

在給料罐出口與管道連接處，管道內物料要滿管，因此該處的彎管曲率半徑要大。輸送管道的起始段好有一定長度的水平管段，至少要比一個料柱長，如必須提升需采用很大半徑的彎管，以使一個料杜穩(wěn)定成形后再上升，無論如何不要在料罐出口后立即提升。

At the connection between the outlet of the feeding tank and the pipeline, the pipeline should be filled with materials, so the curvature radius of the bend at this location should be large. The starting section of the conveying pipeline should be a horizontal section with a certain length, at least longer than a material column. If lifting is necessary, a large radius bend should be used to stabilize the formation of a material column and then rise again. In any case, do not lift immediately after the outlet of the material tank.

輸送完畢一般直接進料倉卸料，為了避免卸料時破碎物料，應從料倉側面進料，如果料倉直徑不夠大，會沖到對面的倉壁上，可將進料管從料倉側面水平伸進料倉，在進料管下部開口下料。為進料倉而垂直提升的料管，在保證足夠彎管半徑的前提下，要盡星靠近料倉以避免料柱提前潰散和壓差過早增大。

After the conveying is completed, the material is usually directly fed into the material bin for unloading. In order to avoid crushing the material during unloading, the material should be fed from the side of the material bin. If the diameter of the material bin is not large enough, it will rush onto the opposite wall of the material bin. The feeding pipe can be extended horizontally from the side of the material bin into the material bin, and the material can be discharged through the lower opening of the feeding pipe. The material pipe that is vertically lifted for feeding into the silo should be as close to the silo as possible to avoid premature collapse of the material column and premature increase in pressure difference, while ensuring sufficient bend radius.

物料的輸送距離

Conveying distance of materials

輸送距離增大到一定程度后，輸送壓力就要提高，但輸送壓力太高會不利于料柱的形成，如果用增加氣柱的方法來增加輸送距離則輸送量就要降低，所以目前對某些物料如不中途補氣就很難實現(xiàn)長距離輸送。

After the conveying distance increases to a certain extent, the conveying pressure will increase. However, if the conveying pressure is too high, it will be unfavorable for the formation of the material column. If the conveying distance is increased by increasing the gas column, the conveying volume will decrease. Therefore, it is difficult to achieve long-distance conveying of certain materials without supplementing air midway.

料柱、氣柱的長度

Length of material column and gas column

料柱比氣柱越長，混合比越大，耗氣量越低，但是料柱長了，壓縮空氣的壓力也要提高，而且容易造成堵塞。如果料柱太短了，料柱容易崩潰，尤其松散、流動性好的物料更易出現(xiàn)這種現(xiàn)象。所以，要根據(jù)物料性質和裝置的具體情況來確定料氣柱比和具體的料柱長度。

The longer the material column is compared to the gas column, the higher the mixing ratio and the lower the gas consumption. However, as the material column is longer, the pressure of compressed air also increases, which can easily cause blockage. If the material column is too short, it is prone to collapse, especially loose and flowable materials. So, it is necessary to determine the material to gas column ratio and the specific length of the material column based on the properties of the material and the specific situation of the device.