How is water hammer formed?

Water hammer, simply put, is the impact of water in the pipes on equipment or pipelines. On one hand, it is the impact caused by the difference in water level during an emergency shutdown； On the other hand, it may be caused by condensed water not having enough time to be drained when steam is supplied too quickly after a short-term shutdown of the steam pipeline before it is restarted. Therefore, for the first issue, a check valve should be installed at the pump’s outlet; for the second issue, the steam valves should be opened gradually

I support the view from the second floor. I have a question: how can this be calculated, and what is the extent of the damage caused by water hammer to the equipment?

The following content is taken from Baidu Baike: Water hammer occurs when there is a sudden power outage or when a valve is closed too quickly; due to the inertia of the pressurized water flow, shock waves are generated, similar to the impact of a hammer, which is why it is called water hammer. The force generated by the back-and-forth movement of water flow shock waves can sometimes be very large, thereby damaging valves and pumps. 　　“The \"water hammer effect\" refers to the situation inside a water pipe, where the inner wall is smooth and water flows freely. When an open valve suddenly closes, the water flow exerts pressure on the valve and the pipe walls, with the valve being the main target of this pressure. Due to the smooth wall of the pipe, the subsequent water flow reaches its maximum velocity rapidly as a result of inertia, thereby causing destructive effects. This is what is known in hydraulics as the \"water hammer effect\", or positive water hammer. This factor must be taken into account in the construction of water supply pipelines. Conversely, when a closed valve is suddenly opened, water hammer occurs as well; this is known as negative water hammer, and it also possesses a certain degree of destructive power, though less than that of the former. 　　When a motorized water pump starts under voltage, it can accelerate from a stationary state to its rated speed in less than 1 second, while the flow rate in the pipeline increases from zero to the rated value. Due to the momentum of the fluid and its degree of compressibility, sudden changes in flow rate can cause pressure surges or drops within the pipeline, as well as cavitation. The impact of pressure exerts force on the pipe wall, generating noise, similar to a hammer hitting the pipe; this is known as the \"water hammer effect\". Water hammer, also known as hydraulic shock. During the transportation of water (or other liquids), sudden changes in flow velocity occur due to reasons such as the sudden opening or closing of valves, the sudden shutdown of water pumps, or the abrupt opening and closing of guide vanes, which in turn cause significant fluctuations in pressure. The instantaneous pressure generated by water hammer can reach dozens or even hundreds of times the normal operating pressure in the pipeline. Such large pressure fluctuations can cause severe vibrations and noise in the piping system, and may also damage valve connections. It causes significant damage to pipeline systems. To prevent water hammer, the piping system must be properly designed to avoid excessive flow speeds; generally, the flow speed in the pipes should be kept below 3 m/s, and the opening and closing speeds of the valves also need to be controlled.

The steam is supplied too quickly, resulting in condensation in the pipes

It’s caused by steam being delivered too quickly, resulting in condensation in the pipes: lol

Water hammer is caused by high-speed steam carrying water droplets, which strike pipelines and fittings in an irregular manner.

I encountered this just a couple of days ago: the pipeline slope was not properly designed, which caused backflow of liquid into the equipment, resulting in uneven bubbling in the bubble reactor and large fluctuations in the liquid level. What was mentioned above makes sense as well

Thank you, great information. Similar **type of transmission

The steam supply pressure or temperature of the boiler is not within the normal range, or the pipes are too long and the pipes were not warmed up before steam was supplied, resulting in water in the steam. I’m not sure if what I said is correct

May I ask what measures can we take in the design to avoid this, aside from adding check valves?

But I’m a steam condensate pipe! Water hammer is extremely severe. What should I do?

How can I download the required materials?

Wealth is necessary; generally, the next attachment requires 1 point of wealth. It can be exchanged for charm, points, etc. There are so many; go check out the newcomer registration area :)

During design, attention should be paid to condensate drainage at the low points. Otherwise, adequate drainage cannot be achieved during operation. The pipe should be thoroughly warmed before operation. The drain pipeline is connected directly to the steam (commonly known as raw steam) before the drain system is put into operation. The water hammer phenomenon has a significant impact on pipelines and equipment. For steam turbines, the typical heating rate is 3–5°C/h; the pipe temperature must be at least 40°C above the steam dew point at the corresponding pressure before the steam can be introduced into the turbine system.