| 摘要 |
PROBLEM TO BE SOLVED: To provide the tank of a septic tank enabling to open a vent hole with an extremely simple method, and an attachment method of the vent pipe to the tank of the septic tank, in the case that the vent pipe is required to be attached to the tank. SOLUTION: The tank of the septic tank consists of polynoryl norbonen resin, and in the tank, a fragile part 16a for fixing a cap part 18a for forming an vent opening enabling to connect with the vent pipe as necessary to the tank, is formed so as to enable to remove the cap part 18a from the tank. The fragile part is formed at least on the outer periphery of the cap part 18a, and it is preferred to be a groove 16a having 40-80% depth D1 with respect to sheet depth (t) of the septic tank and being formed continuously or disconnectly.
|
