The jaw crushers are common types of rock crushing machines which can be found on the market in a variety of sizes and shapes. These machines are generally used as primary crushers, but the smaller jaw crushers can also serve as secondary crushing machines. As a primary crushing machine, the jaw crusher is used for crushing rocks or ores to a manageable size. In general, a jaw crusher is machine that breaks various hard materials into smaller pieces for further processing. The jaw crushers are most commonly seen in mining or disposal sites. These machines are also used in construction sites and processing facilities where they can be either installed or mounted on a building, or can be portable machines which can be moved easily from one location to another. Furthermore, the jaw crusher can be designed as a bucket extension and used with excavators.
For mining operations, the jaw crusher is used for crushing large chunks of rocks into smaller pieces like gravel. This machine often is used as a part of a system composed of several crushing machines which are all used for reducing the size of large materials into manageable size and shape. The working principle of the jaw crusher is quite simple- large pieces of rocks and ores are placed inside the crushing chamber where they are crushed to small uniform size by applying hydraulic force. The jaw crushers can also be used for crushing trash, making it easy for transportation from one to another location. This is very important because the crushed materials are always easier for transportation, loading and dumping. This machine is heavily used on construction sites where a large amount of hard materials need to be crushed on a daily basis, including stones, rocks, concrete, and other form of debris.
There are several jaw crushers on the market, designed with similar configuration and specifications. The double toggle and the overhead eccentric are the most commonly used jaw crushers. Although similar in configuration, each jaw crusher uses different procedure for crushing rocks and other hard materials. One difference between these two jaw crushers is the location of the pivot point. The pivot point is actually the moving joint where the walls of the crushing chamber are connected one to another. In the overhead eccentric jaw crusher, the pivot point located at the bottom, and a rotating wheel is used to assist the moving parts in the crushing chamber. In the double toggle jaw crusher, the pivot point is at the top. The double toggle jaw crushers are more popular option, simply because they are easy to use and consume less energy when compared with the overhead eccentric jaw crushers.
One important thing that needs to be closely considered when choosing which jaw crusher to be used, is the size and the length of the crushing chamber. The crushing chamber should be large enough to allow the materials to easily enter inside. As a general rule, a jaw crusher with larger crushing chamber has more crushing power. Long crushing chambers are suitable for hard materials that demand more strength.