Sectional sampler of crude oil storage tank

The invention discloses a sectional sampler for a crude oil storage tank, which comprises a base, an inner cylinder and an outer cylinder, the inner cylinder is an independent sectional chamber formed by sequentially connecting a plurality of cylindrical inner cylinder units through screw threads, the upper part of the cylinder wall of each inner cylinder unit is provided with a liquid inlet hole, the inner cylinder is located on the base, and the outer cylinder is located on the base. A pair of vertical guide rods are arranged on the two opposite sides close to the edge of the upper surface of the base, lifting ropes with scales are arranged at the tops of the guide rods, the outer cylinder is a cylinder with a top cover, the bottom of the cylinder is open, the inner diameter of the cylinder is slightly larger than the outer diameter of the inner cylinder, an outer cylinder lifting rope is arranged at the top of the outer cylinder, and guide rings arranged on the two guide rods in a sleeving mode are arrange