Spontaneous combustion type fire extinguishing bullet for fire protection

The invention discloses a spontaneous combustion type fire extinguishing bullet for fire protection. The fire extinguishing bullet comprises a sealing cover, external containers and an internal container, wherein the sealing cover adopts a sleeve structure and is divided into an inner ring and an outer ring; threads are arranged on the inner walls of both the inner ring and the outer ring of the sealing cover; a sliding chute is formed in the inner wall of the top end of the external container I; a puncture sharp knife is arranged at the top end of the interior of the external container II; asolution and powdery substance which produces chemical reaction with the solution and produces carbon dioxide are correspondingly contained in the internal container and the external container II respectively; a sealing ring I is arranged at the tail end of the external container II; the sealing ring I adopts a convex structure; the side wall of the upper part of the sealing ring I is fixed on theouter wall of the internal container through a plastic screw. The fire extinguishing bullet is simple in designed structure, easy to carry, easy to operate and high in safety index, cannot cause damage to human body, buildings and other furniture and equipment during explosion, and only achieves extinguishment effect on fire sources.