Overhead loader

Overhead loader - overhead loaders are quite popular in polish mining industry. Their construction is known for a long time and derived from dredge loaders, which after many changes and reconstructions, adapting to the underground conditions, they changed to current form. Overhead loaders are used for loading hard rocks(stone) in a wide range of paving works; predicting lane haulage. They are also used for loading conveyors. Overhead loaders are built in many varieties: - wheeled chassis on a tracks - wheel and tire chassis - caterpillar chassis. Overhead loaders with wheeled chassis on a tracks are the most popular in a polish mining industry.

Advantages and disadvantages:

- simple and compact design, which undoubtedly affects their relatively low price,

- easy operation and maintenance, which provides low exploitation cost

-high certainty of movement.

Disadvantages of overhead loaders:

- high haul of mining bucket, conditioning the height of a pit

- high coal crushing that restricts application to loading hard rocks(stone)

- small front loading space

- large air consumption for a pneumatic loaders.

How it works: Overhead loader mimics the manual cart loading. Mining bucket is equivalent of the shovel and gearing mechanism of mining bucket is equivalent to a worker's muscles, but loading process is similar and consists of three phases: -hammering the mining bucket into a winning -drawing out and haul -unloading. Mining bucket frontally collects a, then during continuous movement and with suitable speed, moves the winning over the loader and sends it to the cart outside the loader. That is why we call them "overhead" loader.

Bibliografia

Górnicze ładowarki chodnikowe, Andrzej Broen, Wydawnictwo "Śląsk" Katowice