It mainly consists of door, hub, opening mechanism, seal ring, tumbler, safety lock plate and pressure relief. The safety lock plate and pressure relief forms the self-locking function (closure self-locking, shake-proof, loose-proof, and with secondary pressure relief). There is no relative rotation between the sealing ring and the seal surface when the closure is locked, the sealing ring is not easy to be damaged so as to protect the sealing system better. The external clamp ring is with three clamps (the contacting area is more than 90%), simultaneous motion with uniform forces when locking. It reduced the length of opening lead screw which makes the opening and closing more flexible and reliable. Meanwhile, it increased the forced area of contacting. It is suitable for natural gas pipeline with high pressure and large diameter. The main pressure parts of quick opening closure are made of integral forged steel without weld assembly.

Band lock type quick opening closure is a kind of mechanical device used for the circular opening of pressure pipeline and pressure vessel. Turning to one side, it can realize quick opening and closing.

Band lock type quick opening closure adopts the inside groove locking band structure, which is designed, manufactured and inspected according to ASME code. It has the characteristics of high machining accuracy, flexible quick opening and closing, safety interlock, compact structure, etc. It is used in petroleum, chemicals, natural gas and other industries. It is widely used in the equipment of pig launcher and pig receiver, filter separator and other pressure vessels.