At present, the application of Lianggong valve in Shanghai is still relatively common in the market. All kinds of valve brands have their own market, which is also related to the hot market environment. However, the valves commonly used in water supply pipeline system include gate valve (thread and flange), stop valve (thread and flange), check valve (thread and flange), butterfly valve, etc.

(1)闸阀：可采用明杆、暗杆、手动、电动、电机驱动。本实用新型具有流体阻力小，启闭力小，介质可从任何方向流动的优点。但结构复杂，闸板密封面易被水中杂质或颗粒摩擦或沉积在阀体底部，造成关闭不严的缺陷。频繁开启的闸阀有时会从阀板上脱落，导致系统失去控制能力。

(1) Gate valve: it can be driven by exposed rod, concealed rod, manual, electric and motor. The utility model has the advantages of small fluid resistance, small opening and closing force, and the medium can flow from any direction. However, the structure is complex, and the sealing surface of the ram is easy to be rubbed or deposited at the bottom of the valve body by impurities or particles in the water, resulting in the defect of loose closing. Frequently opened gate valves sometimes fall off the valve plate, resulting in loss of control of the system.

(2)截止阀：与闸阀相比，具有结构简单、密封性能好、维修方便等优点，但启闭力略大于闸阀。安装时注意阀体上的箭头(水流)方向，不要反向安装。

(2) Stop valve: compared with gate valve, it has the advantages of simple structure, good sealing performance and convenient maintenance, but the opening and closing force is slightly greater than that of gate valve. Pay attention to the direction of the arrow (water flow) on the valve body during installation, and do not install in the opposite direction.

(3)蝶阀：在给水管道上起全开和全关作用的阀门。其启闭力大，但阀体小而轻。

(3) Butterfly valve: a valve that plays the role of full opening and full closing on the water supply pipeline. Its opening and closing force is large, but the valve body is small and light.

蝶阀有很多种，包括手柄式、蜗轮传动式、电动式、气动式等。

There are many kinds of butterfly valves, including handle type, worm gear drive type, electric type, pneumatic type, etc.

(4)止回阀：又称止回阀，它是一种只允许介质单向流动的阀门，因此具有严格的方向性。主要用于管道上防止水倒流。

(4) Check valve: also known as check valve, it is a valve that only allows one-way flow of medium, so it has strict directionality. It is mainly used to prevent water backflow on the pipeline.

常用的止回阀有提升式和旋启式。提升式垂直盘式止回阀应安装在垂直管道上;提升式水平盘式止回阀和旋启式止回阀应安装在水平管道上。安装时注意阀体箭头方向，不得反向安装。那么上述就是我们上海良工阀门代理为大家带来的全部内容分享了，希望大家可以作为参考!

Common check valves are lift and swing. Lift type vertical disc check valve shall be installed on vertical pipeline; Lift type horizontal disc check valve and swing type check valve shall be installed on horizontal pipeline. Pay attention to the arrow direction of the valve body during installation, and do not install in the opposite direction. So the above is all the content that our Shanghai Lianggong valve agent has brought to you. I hope you can use it as a reference!