Marc Brunet May 11, 2012:

Can you determine whether this Kitz product is a guillotine or a bufferfly valve? If it is of the guillotine type, a reference to its "pipe thread edge' could make sense...

David Gibney May 10, 2012:

A google image search ("weir section" + valve) should clarify if you have a diagram in the source.

nhalenguyenanh (asker) May 10, 2012:

I think it may be the section that act as a barrier in a valve (this is a KITZ product). I'm still not sure about that.

cinefil May 10, 2012:

頭部の間違いではないですか？
ねじに堰は、ないでしょう。
あるいは、何かの堰部に取り付けたねじですか？
でもねじは管用なんでしょう？？？
パイプにも堰はないでしょう。
タンク類なら堰は有りますね。