Have you ever encountered this phenomenon in your life? When you suddenly turn off or turn on the faucet, you will find that the water pipe makes a “boom” sound, and you can even see the body of the water pipe shaking. What’s going on?
What is water hammer effect?
In fact, this phenomenon is called the water hammer effect. The inner wall of the water pipe is smooth and the water flow is unobstructed.
However, when the valve opened by the water pipe is suddenly closed, due to the smooth inner wall of the water pipe, the subsequent water flow will reach the maximum speed under the action of inertia, thereby generating a shock wave of the water flow, which will cause damage to the water pipe valve.
Why is water hammer more likely to occur in winter?
In fact, the reason is mainly due to the material of the water pipes. The water pipes are generally made of plastic, and plastics are brittle and easy to burst in low temperature weather, and the buried hot water plastic pipes pass through repeated cold and hot water alternately. The plasticity of the tube is greatly reduced, the brittleness is increased, and the aging is accelerated.
Once the valve is suddenly closed, the flow of water will launch a violent impact on the valve, and the fragile water pipe will not be able to hold up and burst.
Classification of water hammer effect
The water hammer effect is also divided into positive water hammer and negative water hammer. When the open valve is suddenly closed, the phenomenon that occurs is called positive water hammer, which generally causes a water pipe burst accident.
Negative water hammer, on the contrary, is to suddenly open the closed valve. At this time, due to the pressure problem, it will cause the accident of the water pipe to collapse.
No matter how the positive or negative water hammer damages the water pipe, the loss is only a matter of property, but if there is a water hammer that stops the pump, it will be very serious.
Pump stop hammer is similar to positive water hammer, both caused by the sudden closing of the valve. The difference is that the pump stop water hammer mostly occurs in the power system or electrical equipment. Due to sudden power failure or equipment failure, the centrifugal pump opens the valve and stops, thereby causing the pump stop water hammer.
The maximum pressure of the pump-stop water hammer can reach 200% of the normal working pressure, or even higher. The situation is better, that is, the water is cut off, and the more serious situation is that the pump house is flooded, the equipment is damaged, the facilities are destroyed, and the most serious situation is personal casualties.
Post time: Dec-04-2022