Questions about water hammer

There are detailed theories in the principle of hydraulics. After reading some books, I know that when the water flow rate increases, it will drive part of the air to move in the pipe and cause hydraulic shock. This post was last written by li* Edited by nji on 2009-3-10 23:27 ]

The most common cause of water hammer is steam pipes, especially in the winter in the north. If the steam pipeline maintenance time is too long, the residual steam in the pipe will turn into condensed water. If the steam supply is resumed after the maintenance, the steam valve must be opened slowly. If it is opened too fast, water hammer will occur, which is also called "steam hammer" phenomenon. In severe cases, the blind end flange seal will be destroyed, causing steam leakage, and even seriously damaging the equipment and affecting normal production. In addition, after the concentrated sulfuric acid pipeline is inspected and repaired, if the compressed air that has not been dried is used to purge and resume acid delivery, the concentrated sulfuric acid will vaporize when it encounters water, and water hammer will also occur.

The water hammer phenomenon is mainly caused by the presence of low-temperature water in the pipeline. For example, it is more likely to occur when the equipment is first started after maintenance, so the pipe must be heated when driving, otherwise it will cause relatively large direct economic losses.

Water hammer is a common condition in steam pipelines, also called "water hammer". The cause of water hammer is insufficient heating pipes and condensed water in the pipelines. The specific principle will not be explained in detail. prevention methods: Warm the pipes fully, generally for at least half an hour for medium-pressure pipelines, which refers to cold start. If condensate water is recovered, check whether the trap on the condensate water line is abnormal. Treatment method: Once water hammer occurs, identify the pipeline at that location. Generally, the vibration and sound are loud, so it is easier to judge. Immediately open the low-point guide valve to drain the water.

The water hammer phenomenon occurs in fluid pipelines. Due to a sudden change in the working condition of a certain pipeline part, the flow rate of the liquid changes drastically, resulting in a drastic change in the pressure of the liquid. Example 1. There is low-temperature condensed water in the steam pipeline, or low-temperature water rushes into the steam pipeline. The steam condenses sharply and shrinks in volume, causing a sudden change in the fluid flow rate, and the fluid produces a strong impact due to coherence. ； Example 2. Water hammer may also occur if the pump trips and the check door of the outlet door is not closed. The strong impact caused by water hammer is extremely powerful and can easily cause damage to equipment, pipes, valves, etc. This post was last edited by lxzzl on 2009-3-11 16:09 ]

Thank you to the comrade upstairs for your careful explanation. I see

There are many such phenomena. This is due to the excessive amount of condensed water in the steam pipe. During the steam transportation process under a certain pressure, the steam drives the condensed water to move. If the amount of condensed water is large, the condensed water will impact the elbow when the condensed water moves to the corner of the pipe, causing a loud noise like water hammer. This is also the reason why the elbow part of the steam pipe is easily damaged. Solution: 1. Strengthen the insulation of steam delivery pipes to reduce the generation of condensation water, so that the transported steam contains as little condensation water as possible. 2. Install a trap at every other section of the steam delivery pipeline to eliminate excess condensation water, especially in the bend section or the climbing position of the pipeline where traps are needed.