Pipes are put through a process called galvanized which is essentially adding a layer of zinc to their surface. This protects them from corrosion when they are exposed to harsh temperatures. This is particularly applicable to pipes that are placed outdoors but the principle applies to indoor pipes that are exposed to high levels of humidity.
These pipes were an alternative to the problem of lead contamination. We will talk about it a little later in this piece. First, let’s look at the types of galvanized pipes.
There are two ways of doing this.
The cold galvanizing technique is also called electrogalvanizing. It is a basic level of protection that is done typically by manufacturers to make sure that the cold plating helps them pass quality checks. These pipes are relatively cheaper and are not used for water supply systems. In fact, it is prohibited.
The second technique is called hot-dip galvanizing and it is done by allowing molten metal to react with an iron matrix. This results in a layer of an alloy that is the combination of the underlying metal layer and the outer plating.
The steel pipes first go through a process called pickling after which the iron oxide is removed from the surface of the pipe. Then the steel pipe is rinsed in a solution of zinc chloride or ammonium chloride. This technique ensures that the plating is uniform and the pipe has a long lifespan. It is much more effective than electrogalvanizing.
Galvanized steel pipes are used for plumbing and tubing which requires the steel pipes to resist corrosion when they are exposed to elements like water. They are very well suited to outdoor piping systems, among other settings.
Before the 1970s, galvanized pipes were used in water supply systems during construction. But now these pipes are routinely used in outdoor settings to make fences and scaffoldings where the steel needs to be stronger than the average plumbing system.
They are also used in high-pressure pipelines to transport the likes of natural gas for a long distance. These transmission networks have testing stations (to check the protection mechanism) every 60-62 miles.
At these stations, the pipeline is filled with cathode electrons that check how conducive the pipeline is to rust. The electrons charge the pipe uniformly to galvanize the surface.
Along with the cathode electrons, the pipe is also pumped with a mix of quartz powder and bitumen called electric tannin to make sure the electrons are sealed. If there is a break in insulation that causes the natural gas to leak, the electrons help the personnel identify the spot where the leak took place. This makes repair work easy.
They are very good with abrasion and impact resistance. And the zinc coating makes them stronger in fighting everyday wear and tear.
The zinc coating makes them thicker which makes the pipes tougher and resistant to injury.
Hot-dip galvanizing makes them resistant to erosion.
Typically, household plumbing systems from the service lines to the water main of your house are made of copper. But in older cities, these service lines are made of lead. If your home has galvanized plumbing but the service line is made of lead, you might have reason to worry.
Galvanized pipes are known to collect lead and when the pipes inevitably corrode, the lead build-up is released into the water flowing through the pipe.
Despite all this treatment, these plants are not immune to corrosion. What’s worse is that the rusting happens from the inside which makes it hard to tell if the pipe is in good condition just by looking at it.
The structural integrity of whatever system depends on these pipes gets compromised and there will be leaks. If those leaks are ignored for a long time, it will lead to a collapse.
These pipes also accumulate calcium on the inside over time. This leads to clogging and it wreaks havoc in the pressure system of the pipes while also turning the water in the pipe rusty.
So how do you know when it is time to replace them at home? Here are a few symptoms to look out for.
- You will notice rust at the joints of the pipes.
- The water coming out of the faucets will be brown because of the rust.
- The water pressure will be less than usual because of the calcium build-up inside the pipes.
Back in the day, meaning before the 1960s, this used to be a great way to extend the lifespan of steel pipes. Manufacturers started to galvanize steel pipes as an alternative to lead pipes that were used in the water supply lines at the time. Today though, there are plenty of other options.