Water hammer, or hydraulic shock, can be a serious issue that can lead to major damage. For instance, in 2009, 75 people were killed by the water-hammer effect due to failure in Russia’s largest hydroelectric power facility.

Now, you all must be thinking, what exactly can a water hammer issue be, and how can it be harmful to your home and business? 

Well this phenomenon happens when there is a sudden increase in pressure or waves that stop the flow of water or change the direction of flow in a pipeline system. 

When a valve closes suddenly, it creates a shock in the form of waves due to the high energy of the moving water.

Water hammers can impact your homes, businesses, and industries, leading to major system failures, burst pipes, and costly repairs. Proper installation and regular maintenance are needed to prevent water hammer and protect your plumbing system from harm.

In this article, we discuss the causes, effects, and prevention measures for water hammering, along with how to detect and address the issue effectively.

What Causes Water Hammer?

Water hammering can be caused by many things, such as leaks, fast-acting valves (opening or closing), stop valves, loose pipes, air in the pipe, and high water pressure. The most common causes are:

Valve Closure

A quick-closing valve creates a water hammer. When a valve closes suddenly, water flow velocity changes rapidly, generating a shock to the pipe and pressure on the walls that turn into sound or bursts in the pipe.

The Presence Of Air In The Pipe

The water system commonly traps air, which causes a water hammer. When pipelines fill quickly, water displaces the air quickly, creating pressure surges that can damage pipes and fittings.

Loose Pipe Joints

Loose pipe joints also cause water hammer by trapping air in the system and failing to withstand pressure. Older pipes also work like loose pipes, containing air in the pipeline system. So, a loose pipe can damage the whole water pipeline system.

When pipes are not connected properly, they cannot resist pressure or sudden flow changes. This leads to noise and potential damage in the pipe. So, a tight and secure connection is significant when fitting a water system.

Worn Stop Valves

Worn stop valves cause water hammer if the gland packing is loose or the washers are worn. These valves are always open when the water hammer occurs, which can crash the valve handle and a jumper.

Check Valve Slam Point

When water goes downward, due to gravitational force generating heavy pressure, valves are shut very fast. The liquid can not be compressed, so it causes a water hammer effect.

Upstream Of A Running Pump

When an upstream valve of a running pump suddenly closed. It develops a water hammer effect, a vacuum created after the valve causes compression to damage the pipe.

Effects Of Water Hammer

Water hammers have harmful effects on industries, commercial places, and houses. It may cause bursting pipes and leakage and damage to the shape of the valve. Some of the major effects are pointed out here.

Cracks In Pipe

Water Hammers can crack or create a hole in pipes. When the water flow suddenly stops, pressure develops on the pipe wall due to the momentum of the water flow.

Changes In The Shape Of Valves

When a water hammer occurs, it affects the valve’s shape. The heavy-pressure water waves collide with valves rapidly with high kinetic energy, bending valves from their original shape.

Loud Noise

When water stops suddenly, it generates a loud noise like hammers pounding on the pipeline. It may happen due to the water’s kinetic energy, which continuously rolls on the pipeline wall. It is also the cause of noise pollution.

Repair Cost

Another effect of water hammer is repair costs due to damage in the pipeline system. This can result in costly repairs or equipment replacements to fix the damaged pipes and restore the system.

The need for maintenance and urgent repairs can cause downtime, leading to further financial losses.

Leaks And Erosion

After the water hammer, leakage in the pipe is a common effect. A sudden pressure surge creates stress on joints, which can weaken over time and result in leaks. This problem is mainly in old systems, where regular maintenance is important. 

Sometimes, it is small, but it may be bigger, which can damage the properties. A continuous leak causes erosion that makes the pipe and joints weak.

Also Read More About: Water Leak Detectors

Blown Diaphragm

A diaphragm is used in a pressure tank to separate water and air. When a high pressure develops during the water hammer, the diaphragm blows. After this event, the diaphragm is unable to measure the water flow.

How To Prevent Water Hammer?

Decrease The Speed Of Water

When water flows too quickly and is suddenly stopped by a closed valve, it creates a shockwave that can damage pipes. Slowing the water speed lessens this impact and helps maintain stable pressure.

Experts suggest the water speed should be 4.9 ft/sec or less. This may reduce the chance of water hammering in the system.

Use Slow-Closing Valves

Avoiding the rapid-closing valve can prevent water hammering. When a valve closes slowly, it reduces the momentum of water flow and sudden pressure changes. Hence protecting your pipes.

Install Air Chambers

Air chambers are energy recovery systems that help prevent water hammer by acting as cushions. 

When water suddenly stops, the air in the chamber compresses, absorbing the shock and reducing pressure on the pipes. This helps prevent damage and loud banging in the system.

Pipes without air chambers are more prone to damage from water hammers, so it’s important to check your system and install air chambers if needed.

Water Hammer Arresters

A water hammer arrester can prevent water hammering by acting as a shock absorber. When the valve closes very fast and changes the water flow speed, the arrester uses a piston to absorb the shock wave.

This stops the pressure surge from damaging pipes and plumbing systems. Once the shock is absorbed, the piston returns to its original position, keeping the system safe from the water hammer.

Maintenance

If any loose joints or old pipes are present in the water pipeline system, they also cause water hammering, as they lack the stability needed to absorb sudden changes in water flow. So, their routine maintenance is needed.

Pressure Reducers

Pressure Reducers are a type of valve that helps to overcome the water hammer effect. It may be a ball or a rotary valve to install to reduce the high pressure into the lower. A regulator can help slow the flow rate to help prevent the water hammer effect.

How To Detect Water Hammer?

Proper installation and regular maintenance of your plumbing system is important. This can be done with a thermal image process using a thermal imaging camera (infrared camera), an automotive device, such as a surge wave defender, and advanced solutions like smart water meters, it can help detect and mitigate issues before they escalate. Currently, some software detects water hammers in a water pipeline system.

Thermal Image Processing

Thermal imaging can help detect water hammer by showing temperature changes in pipes. Using the thermal camera, experts can find parts of the pipe with big temperature changes.

When water flow and pressure change suddenly, it causes certain parts of the pipe to heat up or cool down. A thermal imaging camera can spot these temperature differences, making it easy to find where the problem is happening. 

Once they find these areas, they can figure out the cause and fix the problem to keep the pipes safe. This method is simple, non-invasive, and helps identify issues quickly to prevent bigger damage.

Monitoring

A regular monitoring process can detect water hammers. Regularly checking pressure and loose pipes prevents water hammering effects.

Conclusion

Water hammering is a harmful issue that affects industry, houses, or commercial places, leading to pipes bursting, leaks, noise pollution, and costly repairs. 

While it may not always be entirely preventable, steps can be taken to minimize its effects. By installing air chambers and water hammer arresters, decreasing water speed, along with regular maintenance, you can protect your water pipeline system.

Additionally, for expert advice, contact your plumber and secure your piping system against water hammer or hydraulic shocks.

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