1.Principle of trough chain conveyor. Trough chain conveyor is a continuous conveying equipment, which can transport bulk materials, like powder small particles and pieces, horizontally and vertically. When conveying materials, the chain of scraper is buried in the materials, and the internal friction and side pressure characteristics of the bulk materials are used to drive the materials forward, so it is called Trough/Drag Chain Conveyor. When conveying horizontally, the material is pushed forward by the scraper chain. When the internal friction between the material layer is greater than the external friction between the material and the slot wall of the machine, the material moves forward with the scraper chain and forms a continuous whole material flow with the scraper chain. When conveying vertically, the material is pushed upward by the scraper chain, the friction caused by the lateral and lateral pressure, and the push from the lower part to the upper part. Which is greater than he external friction between the material and the slot wall and its own gravity, the material moves upward with the scraper chain. At the same time, in the vertical transport, the material will arch, the material arch with the scraper chain vibration in motion will destroy scattered, forming material than scraper chain lag phenomenon.
 

2.Type selection of Trough /Drag Chain Conveyor
2.1According to material characteristics, the operation efficiency of the Trough/Drag Chain Conveyor is closely related to material characteristics. For high temperature materials, such as steam and fried softening materials, expanded materials, billet and finished meal, the shell should choose high temperature resistant material. For strong leakage, inflammable and explosive materials, such as soluble wet meal, a stable joint should be equipped. For wear strong materials, such as soybean, rapeseed raw materials, should choose wear-resistant conveyor, machine groove should be added wear-resistant lining plate, bend arc road to do wear-resistant treatment. Double-layer trough chain conveyor should be adopted for a multiply crushers, embryo rolling machine, expansion machine, oil press’s feed to prevent tail return or storage. For materials with good dispersion, such as soybean meal, the scraper with large enveloping coefficient and complex shape should be selected. For major materials, such as soybean raw materials, choose a wide slot, high strength and stiffness of the scraper; when Conveying for the viscosity of the material, such as softening material, expanded material, simple structure scraper is selected to facilitate cleaning and unloading. When conveying fragile materials and reducing noise, choose non-toxic abrasion resistant plastic scraper.
2.2According to the technological requirements. After defining the material characteristics, according to the position of the inlet and outlet, a reasonable layout form of Trough/Drag Chain Conveyor is selected to determine the length and inclination Angle of the buried scraper conveyor. Then the model of Trough/Drag Chain Conveyor is determined according to the width, height and speed of scraper chain.
3.Common situation of Trough/Drag Chain Conveyor vegetable oil plant. When the process equipment is arranged, the installation foundation, support and maintenance platform shall be arranged reasonably according to the site conditions. When the buried scraper conveyor is installed outdoors, the motor drive position shall take rainproof measures to prevent the motor from being affected with moisture. If it is installed in the pit, the space for maintenance should be spared. The scraper chain is deformed and elongated in the process of use, and the chain becomes loose. The granular material enters the bottom of the scraper chain, making the chain float on the material and compressing the height of the machine groove. In serious cases, the chain will be stuck in the scraper, reducing the conveying efficiency.Sleeve roller chain should be selected as scraper chain for materials that are easy to generate floating chain
This paper provides references for designers, constructors and managers who are in contact with this type of conveying equipment in the plant oil plant for the first time through the introduction of principle, type selection and common problems of trough chain conveyor.