We were discussing “Hydraulic flow control valves”
in our previous post, where we have seen the basic concept and application
concept of flow control valves in hydraulic units. We have also seen the
pressure compensated flow control valve and non-pressure compensated flow control valve in our previous posts.
Today we will concentrate here the gate valve with
the help of this post. Gate valve is
basically used in fluid pipelines for controlling the flow of fluid. There will
be one gate or wedge in gate valve and it will control the fluid flow. Shape of
gate or wedge of gate valve will be a type of flat circular plate or
rectangular plate. Sometimes, gate or wedge is also termed as disc of gate
valve.
There will be one handle wheel, as shown in figure,
with valve which is used to open and close the gate valve. When handle wheel will
be rotated, it will move the gate or wedge in upward or downward direction across
the line of fluid flow.
Gate
Valve
We can see here the figure of a gate valve, where we
will come to know that there will be two section of gate valve. Bottom section
will be connected with the inlet line and outlet line with the help of flanges
and upper section of gate valve will consist with the gate and steam. Handle
wheel and gate will be attached with this stem with the help of pin assemble or
screw assemble.
Working mechanism of a gate valve
Working of gate valve is displayed here in following
figure. When handle wheel will be rotated in clockwise direction, steam and
gate will move in downward direction across the fluid flow line and gate will
be tightly located between the two seats. Hence there will not be any leakage
of fluid through the valve once valve is closed completely.
Working
of gate valve
When handle wheel will be rotated in anti-clockwise
direction, steam and gate will move in upward direction across the fluid flow
line and valve will be opened from closed position and will permit the flow of
fluid through the gate valve. Once gate valve is completely opened, it will
permit no resistance or very little resistance to the flow of fluid.
We can use gate valve in semi-open condition also
but there will be one issue of erosion of gate as fluid will strike the gate if
valve is partially open. Therefore gate valve should be used in completely
closed or completely open condition.
We will discuss Globe valve working principle in our
next post.
Do you have suggestions? Please write in comment box
Image courtesy: Google
No comments:
Post a Comment