Views: 6 Author: Site Editor Publish Time: 2022-11-18 Origin: Site
Introduction of Grab Bucket Overhead Crane
 | Basic Information Of Grab Bucket Overhead Crane |
Grab bridge cranes are widely used in power plants, freight yards, workshops, docks, etc., for loading and unloading of bulk materials. The cranes are heavy-duty working systems, and the working level is A6. All mechanisms are operated in the cab. The directions for entering the platform door of the driver's cab are: end entry, side entry, and top entry. The rated lifting capacity includes the grab bucket's own weight. There are two types of grab opening directions: parallel and vertical to the main beam. The pick-up device is a four-rope grab bucket with two drums, which has a simple structure and reliable operation. The grab can be opened and closed at any height. Grab buckets are only suitable for bulk materials in a natural accumulation state. When grabbing underwater materials or special materials, it must be specified when ordering. The crane can be used indoors or outdoors, and a rain cover device is added for outdoor use.
 | Structure And Working Principle Of Grab Bucket Overhead Crane |
The grab bridge crane is mainly composed of box-shaped bridge frame, grab trolley, cart running mechanism, driver's cab and electrical control system. The fetching device is a grab bucket capable of grabbing bulk materials. The grab bridge crane has an opening and closing mechanism and a lifting mechanism, and the grab is suspended on the opening and closing mechanism and the lifting mechanism by four steel wire ropes. The opening and closing mechanism drives the grab bucket to close to grab materials. When the bucket mouth is closed, the hoisting mechanism is activated immediately so that the four steel wire ropes are evenly loaded for lifting work. When unloading, only the opening and closing mechanism is activated, and the mouth of the bucket opens immediately to tilt the material. Except for the different lifting mechanism, the grab bridge crane is basically the same as the hook bridge crane.
 | Grab Characteristics |
Grab Type | Light | Medium | Heavy | Extra Heavy |
Bulk Density/t·m | 0.8~1.2 | >1.2~2.0 | >2.0~2.8 | >2.8 |
Self-Weight to Material Weight Ratio | 0.75~0.8 | 0.9~1.0 | 1.2~1.4 | 1.5~1.6 |
Applicable Materials | Medium Lump Coal, Coke, Slag, Water Mud | Limestone, Bulk Coal, Peat, Sand in Water, Flaky Iron Oxide Scale | Iron Ore, Fine Ore, Heavy Clay, Rod-shaped Iron Oxide Scale | Bulk Ore, Bulk Manganese Ore |
| Precautions For Grab Bridge Crane |
(1) Check the opening and closing mechanism of the grab and the tightness of the jaw plate closure before each shift, and check the fixation of the jaw plate, the hinged condition of the strut and the lubrication status of each point of the grab.
(2) Check the condition of the guide wheel of the grab opening and closing rope and the fastening and connection of the grab hanging rigging.
(3) Empty test run, check the correctness and reliability of the grab closing mechanism.
(4) It is not allowed to use grab buckets to grab whole objects, and it is not allowed to use grab buckets to lift and unload feeding equipment and railway vehicles.
(5) When the grab is unloading, the height from the hopper shall not be greater than 200mm.
(6) When lifting the grab bucket, the speed of the closing rope and the hoisting rope are equal, and the force on the wire rope is even.
(7) The upper limit position of the grab when it is lifted is that the top of the grab is ≥1m away from the upper limit switch, and when it is lowered, the distance between the bottom of the grab and the hopper and the carriage is ≥0.1m.