Pressing methods of soybean
We know oil press can used to process many kinds of oilseeds, such as rapeseeds, sunflower seeds etc. Soybean is a low oil bearing crop. The oil in soybean is 11-20%, and the water content is usually 13-14%. Before pressing, soya beans need be done some pre-treated process such as selecting and impurity removing etc. Moreover, In order to improve the oil output, the soybean also need be crushed, softened, heated before pressing.
Before starting the oil press, the main operation process is selected soybean using sieve machine, and then get rid of the impurity and stone. Crushed the soybean into 2-4 pieces using crushing machine and soften the seeds within 40 minutes. Then open the oil press and make the chamber temperature reach 110-120 degree, then the soybean can be put in the oil press for pressing. The oil output can reach 5% if the soybean can be pre-treated as above processing steps. We call this process is hot pressing.
The oil press divided cold pressing and hot pressing. For cold pressing, soybean is pressed directly, but must pay attention to control water content at 8-10%. The oil press removed empty for a while and then pressed the soybean when the temperature reach 80 degree. For cold pressing, the soybean usually need be pressed 2-3 times in oil press. Moreover, the oil residual is higher than hot pressing.
There are also some problems when pressing the soybean, depending on our experience, there is some main problems such as there is oil return into the hopper, it is because too smaller gap among plates, so please adjust gaps rods with pad, and loosen tightening nut to increase gaps among round plates. Another problem which our customer often meets is sometimes, the machine blocked, the reason is the pressure of oil press is too higher, so please adjust the distance of pressing worm and pressing ring. These are all small problem for new user. It is no problem to operate our oil press if you read our operation manual carefully.