| 摘要 |
PROBLEM TO BE SOLVED: To provide a scum skimmer capable of more lightly performing the rotational driving of a skimmer pipe. SOLUTION: This scum skimmer has a skimmer pipe which is provided with a bored scum introduction port and is inserted into and passed through a hole formed on the stationary side of the skimmer and also supported through a watertight means so as to be freely rotatable back and forth, wherein on one of the outer periphery of the skimmer pipe side and the inner periphery of the stationary side, a grooved ring having a groove the width of which is gradually narrowed toward the innermost side of the groove, is placed and on the other, an engagement ring capable of being engaged with the inside of the grooved ring through a circular contact surface is placed to form the watertight means with the both rings. |
