Fire-fighting steel cylinder marking device

The invention relates to a fire-fighting steel cylinder marking device which comprises a conveying mechanism and a marking mechanism, the conveying mechanism comprises a conveying frame, a plurality of conveying rollers rotationally arranged on the conveying frame and a conveying belt arranged outside the conveying rollers, limiting ring grooves are formed in the conveying rollers, a limiting groove is formed in the middle of the conveying belt, and a steel cylinder to be marked is limited in the limiting groove; the limiting mechanism comprises limiting seats arranged on the two sides of the conveying frame, limiting frames arranged on the limiting seats and a plurality of limiting rollers rotationally arranged on the limiting frames, the two limiting frames relatively slide in the direction perpendicular to the conveying direction of the steel cylinders, and the limiting rollers are distributed in the circumferential direction of the steel cylinders to be marked; the axis of the limiting roller is perpendic