ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

离心泵是如何工作的 – 译学馆
未登录,请登录后再发表信息
最新评论 (0)
播放视频

离心泵是如何工作的

How does a Centrifugal pump work ?

Centrifugal pumps are the most preferred
在液压领域的泵送装置中
pumping devices in the hydraulic world.
离心泵得到广泛应用
In this video, we will have a conceptual overview
在这个视频中 我们将对离心泵的工作原理
of working of centrifugal pumps.
做一个简要概述
At the heart of the system lies the impeller.
系统的中心是叶轮
It has got a series of curved vanes,
叶轮由一系列弯曲叶片组成
fitted inside shroud plates.
内部安装了护板
The impeller is always immersed in water.
叶轮总是浸在水中
When the impeller is made to rotate,
当叶轮转动时
it makes the fluid surrounding it also rotate.
带动周围的液体流动
This imparts centrifugal force to the water particles
水分子受到离心力作用
and the water moves radially out.
被甩向叶轮外缘
Since rotational mechanical energy is transferred to the fluid,
因为转动机械能转移至液体中
at discharge side of the impeller,
所以在叶轮的排出口
both pressure and kinetic energy water will rise.
水的压力和动能都会增加
At the suction side water is getting displaced,
在泵入口 水流不断涌入
so a negative pressure will be induced at the eye.
所以叶轮中心会产生负压
Such a low pressure helps suck in fresh water strain
负压条件有助于叶轮泵入更多液体
and this process continues.
使整个流程不断进行
This is the reason why priming is important for centrifugal pumps.
这就解释了离心泵充水启动的重要性
If no water is present initially.
如果启动时没有水
the negative pressure developed by the rotating air at the Eye of impeller
在叶轮中心 叶片将很难推动空气
will be negligibly small to suck fresh stream of water.
产生将水泵入叶轮中的负压
Impeller is fitted inside a casing.
叶轮的内部有导流壳
So the water moving out will be collected inside it,
排出的水收集在里面
and will move in the same direction of rotation of impeller,
然后顺着叶轮的转动方向流动
to the discharge nozzle.
至叶轮排水口
Here you can note one speciality of casing.
此处你能看到一个特殊导轮
It has got increasing area along the flow direction.
沿着液体流动方向 为水流提供更多空间
Such increasing area will help in accommodating, newly added water stream
这部分空间能帮助叶轮适应新增水流
and will also help in reducing exit flow velocity.
也能减小液体排出时的流速
Reduction in flow velocity
减小流速后
will result in increase in static pressure,
就会增大静压
which is required to overcome resistance of pumping system
产生静压是克服离心泵阻力的必要条件
Here you can see more details of veins inside impeller.
由此 你可以看到叶轮内部的更多细节
They are backward curved vanes
叶片向后弯曲
with state-of-the-art Eye configuration
是目前最先进的构造
This vane is extracted from a KIRLOSKAR pump model.
该叶片来自Kirloskar泵模型
If pressure at suction side of an impeller
若叶轮泵入口处的压力值
goes below vapor pressure of water,
低于水蒸气压
a dangerous phenomenon could happen.
可能会发生危险的情况
Water will start to boil forming vapor bubbles
水开始沸腾 产生气泡
and spoil impeller materials over time
随着时间推移 不断破坏叶轮组件
This phenomenon is known as cavitation.
这被称为气穴(气缚)现象
More the section head,
泵入口横截面越大
lesser should be the pressure at the suction side, to lift the water.
泵入水流时产生的压力越小
This fact puts a limit to maximum suction head a pump can have.
这一条件限制了泵入口最大横截面
Careful pump selection is required to avoid problems of cavitation.
故需谨慎选择其大小 以避免出现气穴现象
The current impeller type is enclosed,
目前的叶轮样式是全封闭式的
semi-open and open impellers are also in use
半封闭式和开式叶轮也在使用
depending upon the application.
这根据具体应用而定
If the working fluid is cloggy in nature,
如果液体粘稠
it is preferred to use open kind of impeller.
那最好采用开式叶轮
But they are slightly less efficient.
但他们的工作效率稍低一些
Mechanical design of centrifugal pump is always challenging.
离心泵的机械设计 总是具有挑战性
A shaft is used to connect between the impeller and motor
叶轮和电机之间用轴连接
Since water pressure inside the casing is huge,
因为套管内的水压很大
a proper sealing arrangement is imperative in arresting water leakage
所以需要一个合适的密封装置
through the shaft-casing clearance.
以防止间隙漏水
Mechanical seal or stuffing box based mechanism
这就是机械密封
is used for this purpose.
或使用基于填料函工艺的目的
Impeller is mounted on bearings,
叶轮安装在轴承上
but at the suction side impeller,
但在叶轮泵入口一侧
it is not advisable to fit a bearing,
不适合安装轴承
since it will block the flow.
因为轴承会阻碍液体流动
So bearings have to be fitted at the other end.
所以轴承须安装在另一端
This means impeller is mounted like a cantilever.
也就是说 叶轮就像支架一样
For high flow rate pumps,
对高流量泵体而言
a bearing housing with cooling oil is necessary
轴承外壳需要冷却油
for improving the life for bearings.
以提高轴承的寿命
轴承安装
We thank KIRLOSKAR bothers
感谢klrloskar兄弟
for their technical support, in creation of this video.
对我们制作这个视频的技术支持

发表评论

译制信息
视频概述

离心泵工作原理的简单概述

听录译者

收集自网络

翻译译者

刘小贵

审核员

审核员Y

视频来源

https://www.youtube.com/watch?v=BaEHVpKc-1Q

相关推荐