At present, the jaw crusher on the market is mainly divided into two kinds: one is the old machine common in China; The other is based on foreign products to learn and improve the machine. The main differences between the two types of jaw crusher are reflected in the frame structure, the crushing chamber type, the adjustment mechanism of the discharge port, the installation form of the motor and whether it has hydraulic auxiliary adjustment. This paper mainly analyzes the difference between new and old jaw breakage from these 5 aspects.
1. Rack
Welded frame is generally used in small and medium-sized specifications of products, such as the inlet size of 600mm×900mm crusher. If the frame adopts ordinary plate welding, its structure is simple and the cost is low, but it is easy to produce large welding deformation and residual stress. The new type of jaw crusher generally adopts the finite element analysis method, and combines the large arc transition round corner, low stress area welding to reduce the concentrated stress.
The assembled frame is generally used in large-scale products, such as the crusher with the feed port size of 750mm×1060mm, which has high strength and reliability, convenient transportation, installation and maintenance. The front frame and rear frame are cast with manganese steel, which has a high cost. The new jaw crusher generally adopts a modular design to reduce the type and number of parts.
The old jaw crusher frame generally uses bolts to fix the host directly on the base, which often causes fatigue damage to the base due to the periodic work of the moving jaw.
New jaw crushers are generally designed with a damping mount, which absorbs the peak vibration of the equipment while allowing the crusher to generate a small amount of displacement in the vertical and longitudinal directions, thereby reducing the impact on the base.
2, moving jaw assembly
The new type of jaw crusher generally adopts V-shaped cavity design, which can increase the tilt Angle of the elbow plate and make the bottom of the crushing chamber have a larger stroke, thereby increasing the processing capacity of the material and improving the crushing efficiency. In addition, through the use of dynamic simulation software to establish a mathematical model of the moving jaw trajectory and optimize the design, the horizontal stroke of the moving jaw is increased, and the vertical stroke is reduced, which can not only improve the productivity, but also greatly reduce the wear of the liner. At present, the moving jaw is generally made of high-strength cast steel parts, the moving jaw bearing is made of special aligning roller bearing for vibration machinery, the eccentric shaft is made of heavy forged eccentric shaft, the bearing seal is made of labyrinth seal (grease lubrication), and the bearing seat is made of cast bearing seat.
3. Adjust the organization
At present, the adjustment mechanism of jaw crusher is mainly divided into two structures: gasket type and wedge type.
The old jaw crusher generally adopts gasket type adjustment, and the fastening bolts need to be disassembled and installed during adjustment, so the maintenance is not convenient. The new type of jaw crusher generally adopts wedge type adjustment, two wedge relative sliding control the size of the discharge port, simple adjustment, safe and reliable, can be stepless adjustment. The sliding of the adjusting wedge is divided into hydraulic cylinder adjustment and lead screw adjustment, which can be selected according to needs.
4. Power mechanism
The current power mechanism of the jaw crusher is divided into two structures: independent and integrated.
The old jaw crusher generally uses the anchor bolt to install the motor base on the foundation of the independent installation mode, this installation mode requires a large installation space, and the need for on-site installation, installation adjustment is not convenient, installation quality is difficult to ensure. The new jaw crusher generally integrates the motor base with the crusher frame, reducing the crusher installation space and the length of the V-shaped belt, and is installed in the factory, the installation quality is guaranteed, the tension of the V-shaped belt is convenient to adjust, and the service life of the V-shaped belt is extended.
Note: Because the motor’s starting instantaneous current is too large, it will lead to circuit failure, so the jaw crusher uses buck starting to limit the starting current. The low power equipment generally adopts the star triangle buck starting mode, and the high power equipment adopts the autotransformer buck starting mode. In order to keep the output torque of the motor constant during startup, some devices also use frequency conversion to start.
5. Hydraulic system
The new type of jaw crusher usually uses a hydraulic system to assist in adjusting the size of the crusher discharge port, which is convenient and fast.
Hydraulic system adopts motor drive gear pump quantitative system, select small displacement gear pump, low price, small system displacement, low energy consumption. The hydraulic cylinder is controlled by manual reversing valve and the size of discharge port is adjusted. The synchronous valve can ensure the synchronization of the two regulating hydraulic cylinders. Centralized hydraulic station design, strong independence, users can easily choose according to needs. The hydraulic system generally reserves a power oil port to facilitate the supply of power to other hydraulic actuators.
Post time: Nov-14-2024