SLIP-ON TYPE TUBE FITTING

PROBLEM TO BE SOLVED: To obtain a slip-on type tube fitting which has an excellent self-seal effect at the same level as the inner water pressure even to the outer pressure of the tube, and operates the function to protect the tip of a spigot normally constantly, so as to maintain the preservation function. SOLUTION: A front send core 31 with the U-shape section which covers and closely contacts the outer peripheral surface 23 and the inner peripheral surface 24 of a spigot including from a spigot projection 21 to a spigot top 22; and an O-ring 32 which swells between the front end core 31 and the spigot projection 21, and exercises the sealing function of the clearance with a socket inner peripheral surface; are connected by a high strength seal 37 to form integrally, so as to compose into a structure furnishing a rubber ring 3 engaged to the spigot outer peripheral surface. While the rubber ring 3 covers the spogot inner and outer surfaces including the spigot tip 22 so as to be engaged and fixed to the spigot outer peripheral surface, it exercises the sealing function by cutting the clearance between the socket and the spigot in the ring form, and furthermore, the heal part generates a backup function to receive the pressure, and a self-seal effect regardless of the direction of the inner pressure and the outer pressure is provided.