| 摘要 |
PURPOSE:To improve sealing properties and durability by forming on the sealing surface of a water sealing packing, many concave parts having prescribed depth in the direction of packing wall thickness in a stated interval with each other. CONSTITUTION:A packing S is expanded by compressed air supplied into a blank space A to perform sealing. Here, many recessed parts M are formed on the sealing surface on the packing S, and the wall thickness measured along the cross section of the packing S is slightly increased at a part where the recessed part M has been provided from the wall thickness Tmin at other part to reinforce the strength. Moreover, the recessed part M is arranged into a zigzag shape along a line set at an angle of 45 deg. to the longitudinal and transverse directions on the sealing surface, and a relation among its diameter D, central pitch P and overlapped part X are set as X=D-0.5P>=0. |
