The twin shaft concrete mixer is a mainstream concrete mixer while the single shaft concrete mixer is the early kind. What are their differences? Let’s have a look together.
The mixing process of the twin-shaft mixers not only occurs in the radial direction, but also in the axial direction. The main mixing zone is located in the circumferential direction of the mixing body. During the entire mixing process, the energy value along this direction reaches the maximum, so the mixing space can be fully utilized, so that the aggregate, cement and water get fully mixing.
The mixing principle of a single-shaft mixer is basically similar to that of a self-falling mixer. The rotation of the mixing shaft (blade) is to raise the concrete to a certain height and then make it fall freely to complete a mixing process. Therefore, when the single-shaft mixer is in use, the effective working volume is smaller than the theoretical design volume, and the height of the whole machine is much larger than that of the double-shaft mixer.
The mixing principle of the twin shaft mixer ensures that most of the materials to be mixed are accumulated between the two mixing shafts, which reduces the wear between the mixing arm and the blades and the bottom liner.
It has been proved that only 25% of the blades are worn in the non-main mixing zone, and there is only slight or even no wear in the main mixing zone. The liner of the twin-shaft mixer can be selected from ordinary steel plate or wear-resistant cast iron according to the operating conditions.
Due to the higher circumferential speed of the mixing blade and the rotation track of the blade, the wear of the single-shaft mixer is greater than that of the twin-shaft mixer. Therefore, the blades of the single-shaft mixer uses special steel.
Because the concrete is basically piled up near the discharge gate when the China twin shaft concrete mixer completes the mixing, the discharge takes a short time. The opening degree of the discharge door controlled by the electrical device can be adjusted so that the discharge door will not be stuck when closed. During the unloading process, the blades rotate at a low speed, which is beneficial to remove the concrete remaining in the mixing tank and can effectively avoid the parabolic phenomenon during unloading.
Due to the limitation of the system structure, the opening size of the discharge door of single-shaft mixer is difficult to adjust, which will have a greater impact on the discharge of different proportions of concrete. In addition, the discharge door is easy to be stuck during the closing process, especially in the emergency closing situation.