Patent ID: 10029154

Abstract:
A two-layer leak-proof ball comprises a sheath layer (1), an intermediate body layer (2), a winding yarn layer (3), an inner body layer (4) and a two-layer protective layer (5). The intermediate body layer (2), the winding yarn layer (3), the inner body layer (4) and the two-layer protective layer (5) are tightly set successively at the inside of the sheath layer (1). Also disclosed is the manufacturing method of the two-layer protective layer (5) of the two-layer leak-proof ball. High air-sealed bromide butyl mucilage is injected at the inside of the inner body layer (4), and vulcanized at low temperature, thus a glue film is formed at the inner wall of the inner body layer (4). The inner bag of the two-layer leak-proof ball has high tightness and long service life.