Grain-damage-free corncob internal gas explosion spalling pre-threshing test bed

The invention discloses a kernel-damage-free corncob internal gas explosion spalling pre-threshing test bed, and aims to solve the problems that when an existing corn threshing device breaks the natural and tight arrangement and building state of corn kernels on clusters, external force applied to the surfaces of the corn kernels is large, and kernel damage is difficult to avoid. The pre-threshing device comprises an air pump, a mounting table and a pre-threshing assembly. The air pump is an air supply device of the whole gas explosion spalling pre-threshing test bed, and the tail end of an air supply pipe extending outwards is connected to the tail part of a connecting pipe in the pre-threshing assembly; the pre-threshing assembly is located above the mounting table and fixed to the upper face of a mounting plate in the mounting table through bolts. A spalling pipe in the pre-threshing assembly is inserted into a corn ear mandrel, high-pressure gas is introduced to realize cracking of corn ears, and the natu