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flap gate - seating and unseating head
i am trying to get a clarification on this two terms (seating head and unseating head) as it relates to the design of a flap gate.
appreciate your help. thanks.
check out our whitepaper library.
as i understand it, the seating head is the pressure head required to close the flap valve and maintain the seal. so for head levels less than this the valve is not water tight and allows water in. think of a flap valve on the end of an outfall pipe in a tidal region. as the tide rises the flap valve is there to prevent water entering the pipe.
the unseating head is the pressure head required to lift the weight of the flap and break a seal. think when you have a flap valve on a very shallow pipe. if the depth of water required to open the valve is too high then the line may back up and cause problems upstrema.

2009-09-09, 12:19 PM	#1
huangyhg 超级版主注册日期: 04-03 帖子: 18592 精华: 36 现金: 249466 标准币资产: 1080358888 标准币	flap gate - seating and unseating head flap gate - seating and unseating head i am trying to get a clarification on this two terms (seating head and unseating head) as it relates to the design of a flap gate. appreciate your help. thanks. check out our whitepaper library. as i understand it, the seating head is the pressure head required to close the flap valve and maintain the seal. so for head levels less than this the valve is not water tight and allows water in. think of a flap valve on the end of an outfall pipe in a tidal region. as the tide rises the flap valve is there to prevent water entering the pipe. the unseating head is the pressure head required to lift the weight of the flap and break a seal. think when you have a flap valve on a very shallow pipe. if the depth of water required to open the valve is too high then the line may back up and cause problems upstrema. __________________ 借用达朗贝尔的名言：前进吧，你会得到信心! [url="http://www.dimcax.com"]几何尺寸与公差标准[/url]