Extruder hopper with water retaining device, extruder feeding device and extruder

The utility model discloses an extruder hopper with a water retaining device. The extruder hopper comprises a hollow hopper main body, wherein the main hollow hopper body is used for charging an extruder; a water retaining device which is used for receiving liquid which flows downwards along the inner wall of the main hopper body from the upper part and preventing the liquid from further flowing downwards is fixedly arranged on the inner wall of the hopper main body; and a water outlet which is used for communicating the water retaining device with the outside is formed in the wall of the main hopper body. The utility model further provides an extruder feeding device and a corresponding extruder. Condensate water in the hopper can be effectively collected and is discharged out of the hopper; the quality problem and reduction of the production efficiency, or even damages to equipment and a production accident caused by blockage of a hopper discharge hole due to cementation of a powder additive caused by dropping of the condensate water are avoided; the extruder disclosed by the utility model is suitable for the feeding device for various plastic processing extruders, is further applied to various plastic extruders, and is applied to plastic processing.