进口铸钢法兰截止阀

德国巴赫进口铸钢法兰截止阀概述：Overview of cast steel flanged stop valves imported from Germany by Bach:

进口铸钢法兰截止阀属于强制密封式阀门，所以在阀门关闭时，必须向阀瓣施加压力，以强制密封面不泄漏。当介质由阀瓣下方进入阀六时，操作力所需要克服的阻力，是阀杆和填料的磨擦力与由介质的压力所产生的推力，关阀门的力比开阀门的力大，所以阀杆的直径要大，否则会发生阀杆顶弯的故障。

Imported cast steel flanged stop valve belongs to forced sealed valve, so when the valve closes, pressure must be applied to the valve, so as to force the sealing surface not to leak. When the medium into the valve six from the bottom of the valve, the operating force required to overcome the resistance, is the stem and the packing friction and pressure generated by the media thrust force than the valve off the valve opening force, so the diameter of the valve stem, otherwise it will bend the stem top of the fault.近年来，从自密封的阀门出现后，法兰截止阀的介质流向就改由阀瓣上方进入阀腔，这时在介质压力作用下，关阀门的力小，而开阀门的力大，阀杆的直径可以相应地减少。同时，在介质作用下，这种形式的阀门也较严密。截止阀的流向，一律采用自上而下。
截止阀开启时，阀瓣的开启高度，为公称直径的25%～30%时，流量已达到非常大，表示阀门已达全开位置。所以截止阀的全开位置，应由阀瓣的行程来决定。本类阀门在管道中一般应当水平安装。

进口铸钢法兰截止阀的定义：Definition of cast steel flanged stop valve:   

1、截止阀结构比闸阀简单，制造与维修都较方便。
2、密封面不易磨损及擦伤，密封性好，启闭时阀瓣与阀体密封面之间无相对滑动，因而磨损与擦伤均不严重，密封性能好，使用寿命长。
3、启闭时，阀瓣行程小，因而截止阀高度比闸阀小，但结构长度比闸阀长。
4、启闭力矩大、启闭较费力，启闭时间校长。
5、流体阻力大，因阀体内介质通道较曲折，流体阻力大，动力消耗大。
6、介质流动方向：公称压力PN≤16MPa时，一般采用顺流，介质从阀瓣下方向上流；公称压力PN≥20MPa时，一般采用逆流，介质从阀瓣上方向下流．以增加密封件能。使用时，截止阀介质只能单方向流动，不能改变流动方向。
7、截止阀全开时阀瓣经常受冲蚀。

2、The definition of imports valve:

3、1, the valve structure is simpler than the gate valve, manufacturing and maintenance are more convenient.

4、2, the sealing surface is not easy to wear and abrasion, good sealing, open and close the valve flap and the valve body sealing surface between the relative sliding, so wear and abrasion are not serious, good sealing performance, long service life.

5、3, open and close, the valve flap stroke is small, so the valve height than the gate valve is small, but the length of the structure than the gate length.

6、4, opening and closing torque is large, open and close more laborious, open and close time principal.

7、5, fluid resistance, due to the valve body in the media channel more twists and turns, fluid resistance, power consumption.

8、6, medium flow direction: nominal pressure PN is less than 16MPa, generally use the media from the valve downstream, under the direction of flow; nominal pressure PN = 20MPa, using reflux, medium from the valve on the downstream direction to increase the seal. When the utility model is used, the valve can only flow in one direction and can not change the flow direction.

9、7, the valve is fully open when the valve flap is subject to erosion.

进口铸钢法兰截止阀技术参数：Technical parameters of imported cast steel flanged stop valve: