When it comes to piping, plumbing jobs have fairly specific needs, and they differ depending on the type of plumbing being provided. Naturally, this means that when sourcing pipes, you need to take a few things into consideration, with regards to what you expect to get out of them.
Of course, they need to be strong and long-lasting, but they also need to be safe, resistant to their surroundings, and often, insulated.
Fortunately, all of the common types of piping materials meet these specific needs in one way or another, but they each offer something unique as well.
Here we will discuss the differences between these piping materials in terms of what they are, their drawbacks and advantages, as well as their ideal applications.
These materials include those that are either metal or plastic, and they include the following:
PVC pipes; CPVC pipes; PEX pipes; Galvanised Steel Pipes; Black Steel Pipes;304 Stainless Steel Pipes; and brass pipes.
Plastic Pipes
The first group of materials that we explore will be those that can be categorised as plastics; those made from polymer derivatives to serve fairly specific purposes.
In terms of plastic piping, they all have one major function in mind, regardless of their types. They need to offer similar reliability and quality as other types while coming in at a much lower price than them.
While they differ in how closely they meet the former need for quality and strength, they do all tend to offer a cost-effective piping solution.
Plastic pipes include PVC pipes, CPVC pipes and PEX pipes.
Let’s take a closer look at each of them here:
PVC Pipes
PVC pipes are commonplace, mostly due to the fact that they are inexpensive.
The full term is polyvinyl chloride, and it is the world’s third most used synthetic plastic polymer. The material can be rigid or flexible, but for the purpose of plumbing, is usually the former.
PVC has a high tensile value, is quite hard and resistant to chemicals and alkalis, which makes it perfect for most plumbing tasks.
Benefits
The top benefit of PVC is, of course, its cost-effectiveness. It can be sourced in much higher quantities, and at a much lower price than just about any other type of plumbing material.
It is also remarkably lightweight, which makes installation much easier, and ensures that no unnecessary stress is placed on a structure by its plumbing materials. This also allows it to be cut and shaped with relative ease, unlike metallic pipes which require welding for those purposes.
This also makes installation and handling easier since pipes can be put together without the need for cumbersome and expensive welding equipment. For the most part, there are plenty of other ways of fitting them.
When put in line with its cost-effectiveness, the strength offered by PVC piping is also fairly impressive, albeit not quite where metallic or even CPVC materials are concerned.
One of the best things about PVC piping is that it is easy to source, whether looking at a hardware store or an engineering supply store.
Drawbacks
PVC does have one or two drawbacks, however, particularly with regards to the strength that they offer.
While they are rigid and fairly strong, they don’t stack up to other materials used in plumbing, particularly when supply lines need to be buried. In such cases, PVC is at risk of collapse, so care needs to be taken after installing them.
Another major drawback is that PVC is not ideal for high-temperature applications. This is mostly the result of heat degradation, which can actually leave any water that runs through a PVC pipe to become unsafe to drink, while also causing damage to the pipe itself.
Ideal Applications
While the applications for PVC piping are wide, in the context of plumbing, the few disadvantages do limit their usage somewhat. This is particularly the case because of their inability to handle high temperatures.
This also makes it not ideal for the supply of water that is meant for consumption, since breakdown due to heat may come from external sources even when not attached to a hot-water line.
However, for drainage applications, or for those where water not meant for human consumption is concerned, PVC offers a convenient, affordable and effective solution.
CPVC Pipes
CPVC pipes are like PVC ones, except that they have a bit of added chlorine to ensure even greater protection against degradation (especially due to heat), as well as a bit more strength.
It is a better alternative to PVC wherever hot water is being transferred, and it still offers the same benefit to affordability as its less chlorinated counterpart.
The full term is chlorinated polyvinyl chloride and it offers a maximum operating temperature of 90 degrees Celsius, although it has a melting temperature range of between 220 and 240 degrees. While it is still at some risk to breakdown from high temperatures, it is still far more resistant than PVC.
Benefits
There are several benefits to using CPVC pipes in plumbing, most noticeably when compared to PVC is the fact that they can be used for hot water if the water is not at an excessive temperature (remains below boiling point).
It is also about as cost-effective as PVC piping and is also as readily available from hardware and engineering supplies stores.
Like PVC, it is also resistant to corrosion, is lightweight and easy to handle, requires very little maintenance and offers a long service life before needing replacement.
It also presents a safer material for plumbing applications, which means that it is okay for creating lines that move water for human consumption.
On top of this, it offers better mechanical strength than PVC does, which makes it better for applications where piping needs to be buried.
Drawbacks
Of course, like anything in life, CPVC also comes with one or two drawbacks that you should be aware of.
When compared to PVC, it is easy to see why CPVC is often the better choice; but when the same properties are compared to metallic pipes, they almost always fall short.
When compared to metals, CPVC piping is brittle and is also limited in its capacity for extreme temperatures.
It is also about twice as expensive as standard PVC, but it does offer quite a bit more in terms of durability.
One of the major disadvantages to CPVC is that it has a high thermal expansion coefficient, which means that it will change size when it heats or cools; either from the water, it is transporting or from outside sources.
Ideal Applications
CPVC pipes are ideal for many of the same applications as PVC pipes, except that they offer better strength in doing so. Because of this, they are a cost-effective choice for pipes that need to be laid underground without having to combat the risk of collapse.
They are, however, also okay in terms of safety, so they can be used to transfer drinking water. On top of this, CPVC can withstand moderate temperatures, so they can be used to transfer hot water (they are even better insulated against heat loss than PVC).
Still, wherever extreme temperatures and structural pressure is concerned, CPVC is still just a thermal plastic, which means that it doesn’t have an as high capacity for pressure, stress or temperatures that metal pipes do.
PEX Pipes
PEX is the common term for cross-linked polyethene, and it does pretty much what its name says. It is made up of polyethene links which makes it ideal for a number of specialised applications from plumbing to networking.
The major property to this material is that it is highly flexible, without having to sacrifice anything on strength and durability; a phenomenon that occurs thanks to its cross-linked design.
The next major property to PEX is that it is highly resistant to temperatures, which makes it ideal for a range of plumbing tasks.
Benefits
There are a number of unique advantages to PEX pipes. They offer some degree of cost-effectiveness since they are mostly made up of plastics, however, they do this while offering superior strength and flexibility when compared to its PVC and CPVC counterparts.
The flexibility offered by PEX makes it ideal for closed or tight spaces, but where it really shines is in the range of operating temperatures that they support. They are highly resistant to extreme temperatures, both hot and cold, which makes it ideal for nearly all plumbing tasks.
This also ensures that they last much longer since they don’t suffer heat degradation or cracking from extreme temperature fluctuations.
Metal Pipes: 304 Stainless Steel
In almost any application where stainless steel is a material you can choose, it is the best one; particularly wherever plumbing is concerned.
Stainless steel offers some of the best in extreme resistant properties, especially for applications where water is involved.
Just about any other grade of metal will face problems from both galvanic corrosion and rust, both of which are handled with ease by stainless steel.
It is also a perfectly safe solution as far as drinking water is concerned and is also rated one of the more hygienic materials, thanks to the fact that it is easily cleaned.
All of this does come at an extra cost, however; but in terms of value for money, stainless steel still offers a great deal; purely because of its strength, resistance and heat conductibility.
Benefits
There are near countless amounts of benefits when using stainless steel pipes in plumbing, and they particularly meet the mark where plastic solutions fall short.
Their extreme resistance to rust and corrosion makes it ideal for applications both large and small; stainless steel pipes have as much of a place in the average home, as they do in a factory or plant.
They are also exceptional conductors of thermal energy, which makes them ideal for transferring hot water, even when done so at excessive temperatures.
Stainless steel also has a relatively low thermal expansion coefficient, which means that it won’t be damaged by freezing or boiling water.
In terms of raw strength, very few building materials can match stainless steel, especially when compared to how lightweight a material it is.
Drawbacks
In terms of drawbacks, stainless steel really only has one, and that drawback is the price.
It is known for its strength and resistive power, but this highly coveted metal is also well known for its price per weight.
However, one shouldn’t consider this material in terms of its price, but rather its value for money, which is extensive.
This is particularly the case when you consider how long stainless steel products last, even under the most gruelling conditions. Combine that with a capacity for higher pressures and temperatures, as well as the fact that it is easily sourced in engineering supplies stores, and it is easy to see why so many people are prepared to spend the extra on stainless steel.
Contact D&D Valves for Details
Here at D&D Valve Engineering Supplies in Johannesburg, we have a massive selection of different pipes, valves and fittings to suit your exact needs.
If you would like to know more about our offers, or have any questions for us, feel free to get into contact with one of our representatives today or visit our website for additional details.