A loader is a machine with a bucket working device installed on a wheeled or crawler chassis. Loaders before the 1960s had low power and structural strength and were mainly used for loading and moving loose materials. In recent years, loaders have been improved and enhanced in terms of structure, transmission, materials and tires. Many 5 ton wheel loader can be used in projects such as open-pit mines, quarries and tunnels. Loaders can not only carry out earthwork operations, but also become machines such as cranes or forklifts after replacing the working device. At the same time, they can also be used as tractors. They are a kind of engineering machinery with strong adaptability and multiple uses.

The main parameter of a compact wheel loader is the rated load weight. my country has formulated standards for the product series and basic technical parameters of tire loaders.

Loaders are divided into two categories according to the walking device: tire type and crawler type; according to the different frame structures, they are divided into integral type and articulated type; according to the different working device structures, they are divided into bucket bracket type and bucketless bracket type. In addition, according to the unloading method, it can be divided into four types: front unloading, rear unloading, side unloading and rotary. The most common is the tire, articulated, bucketless bracket, reverse six-link mechanism front unloading single bucket loader, such as the ZL50 model.