Jaw crusher commonly known as smashed, also known as tiger mouth. The jaw crusher consists of two jaws, a dynamic jaw and a static jaw, to simulate the animal's two jaw movements and complete the crusher for material crushing operations. Widely used in mine smelting, building materials, highways, railways, water conservancy and chemical industries in a variety of ore and large pieces of material broken. The highest compressive strength of the broken material is 320 MPa.
Development Overview
The crushing machinery in modern times was successively created after the power machines such as steam engines and electric motors were gradually perfected and promoted.
In 1806, a roller crusher driven by a steam engine emerged;
In 1858, Black of the United States invented a jaw crusher that broke rocks;
In 1878, the United States developed a gyratory crusher with continuous crushing action, and its production efficiency was higher than that of jaw crusher for intermittent crushing action.
In 1895, William of the United States invented a low-energy impact crusher.
In the 1980s, the large jaw crusher that broke 800 tons of material per hour had a feed particle size of about 1800 millimeters.
Commonly used Jaw Crushers have two types of brackets and single brackets. In the former time, the former only makes a simple circular arc swing, so it is also called a simple swing jaw crusher; the latter also makes a vertical motion while making a circular arc swing.
Domestic jaw crusher manufacturers have very different levels of technology. There are a few manufacturers of products that are basically close to the world's advanced level, and most of the manufacturers' products are far from the world's advanced level. Jaw crusher racks account for a large proportion of overall machine quality (50% for cast racks and 30% for welded racks). Jaw crushers abroad are welded frames and even welded structures are used. Jaw crusher using welding rack is the development direction.
In recent years, with the increasing proportion of open-pit mining, and the adoption of large-scale electric shovels (excavators) and large-scale mining vehicles, the ore block density of open-pit mines transported to crushing plants has reached 1.5 to 2.0 meters; The grade of ore is decreasing, and in order to maintain the original production capacity of the concentrator, the amount of ore mined and the amount of mined ore must be greatly increased. Therefore, the jaw crusher is developing in a large scale. At present, the largest jaw crusher manufactured in foreign countries is: 3000 x 2100 mm (Simple Pendulum), giving a lump size of 1,800 mm, a production capacity of 1,100 tons per hour, and 2100 x 1,670 mm (combination), When the discharge port is 355 mm, its production capacity is 3,000 tons per hour.
With the emergence of impact-resistant large rolling bearings, the use of complex pendulum jaw crushers instead of simple pendulum crushers has become a trend both at home and abroad, because the former has a 30% increase in production capacity compared to the latter in conditions where the conditions are comparable; When the production capacity is the same, the former is 20% to 30% lighter than the latter. However, there are still some problems in the structural aspects of the compound pendulum jaw crusher, which remains to be studied and improved.
It should be noted that in recent years due to the improvement of large rolling bearing materials in China and the need for downhole crushing equipment, the complex pendulum jaw crusher also has a tendency to develop in a large-scale direction. Currently, a 900×1200 compound pendulum crusher is being trial-produced. With the increase in the size of equipment, the adjustment device and safety device of a jaw crusher inevitably adopt a new mechanism. Therefore, another trend in the development of jaw crushers currently is the use of a hydraulic adjustment mechanism for the size of the discharge port, which is not only simple and rapid, but can be adjusted at any time according to needs at any time during operation; at the same time, the overloaded safety device of the machine is also hydraulically applied. The mechanism is to be safe and reliable without damaging the thrust plate, and the machine will immediately resume work after the trouble is removed. This type of hydraulic jaw crusher is being vigorously developed at home and abroad. China has produced a 900×1200 hydraulic pendulum jaw crusher and put it into production at the Laiwu Iron Mine and the Roots Iron Mine. The production practice has proved that the insurance mechanism and adjustment mechanism of the hydraulic jaw crusher have achieved the purpose of safety insurance and convenient adjustment and are in good condition. They are welcomed by post workers.
In addition to improving the crushing efficiency of jaw crushers, apart from improving the structure of the original equipment, for example, increasing the height of the crushing chamber and increasing the production capacity; reducing the number of discharge ports and increasing the crushing ratio; In order to increase equipment production capacity and improve product quality, at present, various countries are researching and testing new types of structure crushers, such as impact jaw crusher, double action jaw crusher and hydraulic transmission jaw crusher.
