Roller Ball Press
Roller Ball Press
Source: internal company
Roller ball press is divided into low-pressure ball press, medium-pressure ball press and high-pressure ball press because of the characteristics of the applied materials, uses and different pressure sizes. As for the three pressure definition is not yet a unified standard, generally to line pressure (forming pressure is usually the total pressure divided by the roll skin width, called line pressure) size to distinguish. Currently in rotary hearth furnace process on the application of high-pressure ball press.
Roller ball press mainly relies on two opposing rollers, so that the mixture flowing into the gap between the two rollers by pressure molding (see Figure 1). One of them is a fixed roller, the other is a dynamic roller that can move horizontally back and forth, and the pressure is added to the bearing seat at both ends of the dynamic roller. The difference between high, medium and low pressure ball presses is mainly the difference between the pressurization method and transmission mechanism. Low-pressure ball press generally adopts spring pressurization, while medium- and high-pressure ball press adopts high-pressure cylinder pressurization. The two rollers can be opened on the surface of the groove, the number and size of grooves according to the needs of the design, the product can be egg-shaped, pillow-shaped or oval-shaped.
Figure 1 Roller ball press molding principle diagram
High-pressure ball press mainly consists of pre-pressure device, the main body of the ball press, hydraulic support system to form a unit, see Figure 2.
1. Transmission 2. Coupling 3. Pressure roller 4. Pre-pressure device 5. Inlet 6. Support cylinder 7. Frame
Fig. 2 Schematic diagram of high-pressure ball press
Pre-pressure device consists of two parts, one is the speed motor, coupling, reducer and other transmission parts; the second is a single-head or double-head screw and feeding nozzle pre-pressure device. Its role is to pre-compression of fine powdery materials, degassing, to ensure that the pressure of the material supply to improve the weight of the material. For different varieties and sizes of powder materials, the optimal feeding volume (or speed) is not the same, so the pre-pressure transmission device is required to adjust the speed.
The main body of the ball press consists of two oppositely rotating pressure rollers with half grooves, motor, coupling, reducer, double shaft coupling, and frame. One of the two rollers is fixed, the other is movable, to ensure that the ball pressing process to maintain a constant pressure, when there is a hard object into the safety protection. The double outlet shaft coupling must be flexible in order to adapt to the demand of pressure roller movement. It is better to choose frequency conversion motor for the electric motor, so as to adjust the speed of the roller according to the needs of material characteristics. Because the speed is too fast, there will be more hemispheres, reducing the rate of ball formation and quality of ball formation.
The hydraulic support system is mainly composed of oil tank, oil pump, electric motor, hydraulic valve and oil cylinder.
The key component affecting the efficiency of the molding machine is the ball roller, ball roller blanks are divided into: the whole forging and casting, casting density is small, rough structure, but more economical. Forged from the density of large, compact structure, wear resistance, long life, ball groove processing technology, suitable for a variety of materials, and reliable operation, mostly used in high-pressure large-scale molding machine, but the cost is high.