Have you noticed that the natural shiny surfaces of copper water pipes turn green or black? Do you know why this happens? In the presence of oxygen, copper undergoes an oxidation process that dulls its appearance. In just a few years, this rust turns black or dark brown, and then eventually green. In addition, corrosion can easily enter crevices and fissures in copper pipes.
Even in brand-new houses, copper pipe systems can become hazardous and seep into the water supply if not maintained properly. Often, this type of leaching is a result of unfavourable corrosion. Copper is an essential mineral, thus very low levels of consumption are fine for humans. However, excessive use can induce gastric issues. Kidney and liver failure can develop from chronically elevated copper levels. Treatment is essential if pipe testing reveals a concentration of more than one milligram of copper per litre.
What Happens When Copper Pipes Corrode?
When copper is exposed to air, moisture, and hydrogen sulphide, it breaks down into oxides or sulphides. Corrosion causes pitting, and this causes pinhole leaks. Most of the time, these leaks go unnoticed for months, which lets mildew and mould growth. Pitting weakens the pipe to the point that it unexpectedly breaks, causing extensive damage and repairs. Even though many studies have been done on copper corrosion, it is still hard to fully understand the problem, and fixing it can be challenging. This blog can help you understand the causes of copper corrosion in home piping systems and a few methods to prevent it. Let’s look into it in detail in the following sections.
Six Major Causes of Corrosion in Copper Pipes
1. Acidic water: Water with a low pH level of less than 7.0 is acidic. A high level of acid level in water causes corrosion in copper pipes, which can result in leaks as well as the leaching of copper into your water supply. The severity of the negative impacts on your health will be directly proportional to the amount of copper in the water. Acidic water can even lead to pinhole leaks in copper plumbing systems.
2. The salinity of water: One of the metals with the lowest corrosion resistance is copper. Hence when water with high saline levels goes through copper pipelines, sodium reacts with copper leading to its corrosion. Saltwater corrosion is more difficult to cause in galvanized steel and iron when compared to copper pipes. Although it can nonetheless happen over time. To eliminate saltwater from the pipes, the entire system must be cleansed and then pumped from within. If you don’t flush right, salt can stay in your pipes and destroy the metal over time.
3. Stagnant water: Corrosion is less likely to happen when there is a steady flow of water. Where water doesn’t move freely and is stagnant, outgassing releases oxygen, which then interacts with the copper. Copper oxide is formed if the process goes on for a long time which gives the water its greenish colour. Furthermore, copper typically has a blue-green colour, which can also appear in the system’s apparent limescale deposits.
4. Aeration: Oxygenated water is constantly being added to your water system, which means about 30% of the oxygen and 70% of the nitrogen in the air have dissolved into the water. The oxygen dissolved in water when passed through pipelines eats away the metal. This is called oxidation. We can easily identify this when the metal turns into oxide or rust. As more of the metal rusts, the pipe gets thinner and weaker. Over time the uneven surface inside the pipe caused by the rust acts like a magnet for water pollutants and traps them inside the pipes. The metal in your pipes wears down, making them more likely to break. Also, it leads to the formation, of pinhole cracks, or pipes breaking when pressure is put on pipes that are already weak.
5. Presence of chlorine and sulphites: To clean up the local water, maintain it free of bacteria, and make it safer to drink, we usually add sulphites and chloramines. Chloramines are chemical substances that increase the ability of chlorine to disinfect drinking water by combining it with ammonia. Unfortunately, the result of these chemicals on copper is corrosion and leakage. In the last few years, the standards for safe drinking water have gone up, and as a result, the amount of time that buildings can use their copper supply pipes has gone down.
6. Electrolysis: Electrolysis can happen when there is a direct-current electrical leak underground. This kind of leak often damages copper pipes. Electrolysis can also happen when two metals that are not the same touch each other. For instance, if a plumber repaired the main water line of your house and connected a brass pipe to the old galvanized pipe, this could result in electrolysis and damage to the water line. Some indications of electrolysis are a strange smell, green stains on the pipe, and corrosion, which you might not notice because the pipes are underground.
Five Strategies for Preventing Corrosion
1. Ensure the water you use is good: Water is a major cause of corrosion. Copper pipes may become corroded if the pH is too low. Your water’s pH level should remain in the range of 6.5 and 8.5 at all times. You must also pay attention to the amount of oxygen in your water. Oxygen causes rust, can accumulate, and can impede motion in objects. Another smart move is to maintain the water temperature as low as feasible. Hotter water tends to cause more harm to objects.
2. Clean the pipes: When corrosive bacteria are present near metals, microbiologically induced corrosion occurs. To stop MIC, it’s smart to clean pipes, especially if they’re often in contact with sulphides. You can keep fluids clean by using inhibitors or biocides. Chemical treatment of water is an additional choice.
3. Protect metals of the pipes: Pipes and other surfaces can be kept from rusting by linings or coatings that protect them. This includes beams, joints, and bolts, among other things. For example, galvanization works by coating steel or iron with a thin layer of zinc. Use a sealant to stop corrosive bacteria from getting into cracks and joints in the first place.
4. Keep structures stable: Metal gets worn down by friction, shaking, and bouncing. Crevice corrosion happens when corrosive materials get into spaces that are starting to open up. The use of a restraint is a good way to stop crevice corrosion. Vibrations that can cause corrosion can be cut down with U-bolts, straps, and clamps.
5. Make sure metals do not touch each other: Some metals don’t get along. This is called galvanic corrosion when one metal takes electrons from another metal. This makes the section weaker and puts the whole structure at risk. Insulating the metal is the most effective approach to prevent corrosion between metals. Consider installing insulators for piping, like wear pads or pipe shoes. Insulators put a space between two metals, which helps the metal last longer.
Many different things can affect supply pipes. Both the root causes of the pipe damage and any situations that may have worsened the situation must be identified before a lasting solution can be found. Also, it is crucial to take precautions against corrosion when installing a plumbing system that uses copper pipes. Avoiding corrosion requires an understanding of its root causes. Moreover, corrective action is required without delay to prevent further corrosion.