Double-channel block valve

The invention discloses a two-channel block valve, and relates to the technical field of block valves. The mechanical iris mechanism is arranged on the outer side of the inner pipe in a sleeving mode and comprises a shell, a plurality of cut-off pieces and an operation ring, the shell is annular, the shell and the inner pipe are coaxial, the cut-off pieces are movably arranged in the shell, and the operation ring is rotationally connected with the shell; when the operation ring rotates relative to the shell, the multiple cut-off pieces can be driven to move in the direction close to the inner pipe till making contact with the outer wall of the inner pipe. The inner pipe is arranged in the cut-off valve, only the peripheral space of the inner pipe is cut off during cut-off, material circulation in the inner pipe is kept, and the use requirement of partial cut-off is met. 本发明公开了一种双通道截断阀，涉及截断阀技术领域，包括：内管；机械虹膜机构，套设于内管的外侧，机械虹膜机构包括壳体、多个截断片和操作环，壳体为环形，壳体与内管同轴，截断片可移动地设置在壳体内部，操作环与壳体转动连接，操作环相对于壳体转动时能够带动多个截断片向靠近内管的方向移动直至与