Pile casing for round gravel layer pile foundation construction

The utility model discloses a pile casing device for gravel layer pile foundation construction, and relates to the field of pile foundation construction pile casings, the pile casing device comprises a lower pile casing and an upper pile casing, the lower pile casing is located at the bottom end of the upper pile casing, a plurality of fixing reinforcing ribs are installed on the periphery outside the lower pile casing and the upper pile casing in a welding mode, a groove is formed between every two adjacent fixing reinforcing ribs on the two sides, and the grooves are communicated with the lower pile casing and the upper pile casing. Movable reinforcing ribs are embedded in the grooves, movable mounting grooves are formed in the upper ends of the sides, close to the grooves, of the fixed reinforcing ribs on the two sides, and arc-shaped clamping blocks are arranged at the ends, close to the grooves, of the interiors of the movable mounting grooves. The anti-pressure capability of the upper pile casing and th