翻转式阀瓣止回阀由圆柱形外壳及转动圆盘阀瓣构成。枢轴就位于阀瓣中心上，偏离阀体阀座平面。这种结构使得阀瓣能够进行钟摆式运动。圆盘斜角形阀座和漏斗形阀瓣结合和分离期间都不会出现摩擦或滑动接触。
Tilting Disc Check Valves consist of a cylindrical
housing, with a pivoted circular disc. The pivots are located just above
the center of the disc, and offset from the plane of the body seat. This
design gives a bell-crank action to the disc. The seat is of circular
bevel type and the disc drops in or out of contact without rubbing or
sliding.
特点
Features
止回阀的撞击现象，是由于在流体倒流之前，阀门的阀瓣没有到达关闭位置造成的。翻转式阀瓣止回阀能够迅速关闭，这是由于阀瓣的运行距离很短，因此能够迅速到达阀座位置，从而最大限度减小撞击现象。
Slamming of check valves is the result of failure
of the valve disc to reach its closed position before the fluid flow reversal.
Tilting disc check valves have to close rapidly since the disc has a shorter
distance to travel and therefore arrives at the seat faster...minimizing
a slam.
翻转式阀瓣止回阀适用于防止水平或垂直管路上的流体倒流。在垂直管路，或水平到垂直之间的任何倾斜角度的管路上，这些止回阀仅适用于流向朝上的管路。
Tilting disc check valves are used to prevent
reversal of flow in horizontal or vertical pipe lines. In vertical lines,
or for any angle from horizontal to vertical, they can be used for upward
flow only.
翻转式阀瓣止回阀自动运作。它们在流体流速压力下开启，在重力作用下关闭。阀座密封负载和紧密性与反压力相关。如果流速压力不足于将阀门支撑在敞开的、稳定的位置，则阀瓣和其它活动部件将会持续振动。为了避免出现运动部件的过早磨损、噪音或振动运行，就要根据流体状态选择止回阀的通径。能够将翻转式阀瓣止回阀支撑在敞开的、稳定的开启状态所需的最小流体速度，需要通过下列公式进行计算得出：
Tilting check valves are automatically actuated.
They are opened by velocity pressure, and closed by gravity. Seating load
and tightness is dependent on back pressure. The disc and moving parts
may constantly move if the velocity pressure is not sufficient to hold
the valve in a wide open and stable position. Premature wear and noisy
operation or vibration of the moving parts can be avoided by selecting
the size of check valve on the basis of flow conditions. The minimum velocity
required to hold a tilting disc check valve wide open and stable can be
determined by the formula:
v = 80 
v值表示流速，单位为英尺/秒； 是流体比容积，单位为立方英尺/磅。通过这种方式确定的止回阀通径，可能会出现所确定的止回阀通径小于管道通径，因此在安装时，可能需要安装减缩管。所产生的压降不能大于那些处于部分开启状态的通径较大的阀门，这样将大大延长阀门的使用寿命。这当然还带来额外的好处，那就是通径更小的阀门，成本也相应更低。
The value for v is equal
to flow in feet per second and
is the specific volume of fluid in cubic feet per pound. Sizing swing
check valves on this basis may often result in the use of valves that
are smaller than the pipe in which they are used, necessitating the use
of reducers for installation. The pressure drop will be no greater than
that of the larger valve that is only partially open, and valve life will
be greatly extended. The added bonus, of course, is the lower cost of
the smaller valve.
标准阀体结构配置
Standard body design configurations
阀座，阀瓣和枢轴销构成一个分总成，采用尺寸3英寸或更小的锁环固定在阀体进口一侧。这种结构消除了将枢轴销伸长穿出阀体的必要性。
The seat, disc and pivot pins are combined into
one subassembly secured to the inlet side of the body with a locking ring
in sizes 3" and smaller. This construction avoids the need for extending
the pivot pins through the valve body.
DN100及以上通径的阀门，其阀座采用钴基合金硬面材料制成，装配在阀体进口一侧。支撑阀瓣的枢轴销插在阀体出口一侧的阀帽和垫圈轴承座上。
The seat formed on the end of the inlet body section
by cobalt base alloy hard facing deposit in sizes 4" and larger.
The pivot pins supporting the disc are inserted through capped and gasketed
bearing bosses in the outlet section of the body.
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