An Overview of the Commonly Used PVC Pipe Fittings

Any task that involves installing PVC pipes needs to be done right the first time. For this reason, it’s really important to thoroughly understand the different types of PVC pipe fittings before you begin.

Learn the basics here with a friendly, knowledgeable PVC pipes and fittings supplier in the UAE. 

What are the different uses for PVC pipes and their fittings?

PVC is a highly durable, strong, low-cost and non-toxic material. This makes it ideal for various types of piping, which may be used in projects in your own home up to vast main infrastructure projects. 

The three main uses for PVC are for:

1. Pressurized water (i.e., in household and industrial water supply, irrigation, and sewage rising mains) 
2. Duct piping for encasing cabling
3. Drainage piping, both underground and overground

No matter what you intend to use PVC piping for, there are a few things you must get right. These are:

• Choosing the right fittings
• Sizing
• Scheduling
• Sealing

Read on to find out more about all the above so that you can make the right choice. 

Choosing the right fittings

PVC pipe fittings are the items that complement a standard straight length of pipeline. There are many different types of fitting that do various jobs, such as allowing your pipe system to turn corners, split into different pipelines and much more. Here are the most common fittings that will help you customize your system.

Couplings

A coupling is a simple fitting that allows you to connect two pipes of any length and continue a straight line. Note that unions do the same job but are not designed to be permanently sealed into place.

Elbows

Elbows are easily available in 90-degree and 45-degree angles. They help your pipe system turn corners and bends. 

Tees

Like a capital T, these have 3 ends to join 3 pipes at a junction. You might use this fitting to split 1 line into 2 or the reverse, 2 lines into 1.  

Crosses

As the name suggests, these have 4 ends in a + shape. As well as dividing lines and flow, they can help add structural integrity to a large system. 

Caps and plugs

Both caps and plugs are designed to stop flow and mark the end of a route. Caps go on the ends of pipes, whereas plugs sit within a fitting. 

Adapters, reducers and bushings

Adapters and reducers are fittings that enable you to connect pipes and fittings of different sizes. Bushings fulfil the same role but are part of a fitting.

Flanges

A flange allows you to connect accessories to a pipe system, for example a toilet. They are a disc-like fitting that uses bolts or clamps to create a tight seal between the pipe system and accessory. 

Nipples

Nipples are only needed in systems that use PVC pipes with thread joints. You would use this when two female threaded pipe fittings need to be joined together. Nipples contain two male threaded ends to enable this. 

Sizing

Both PVC pipes and fittings come in various sizes. The size references the internal diameter of the pipe or fitting. So a 1” fitting or pipe will have an internal diameter of 1”, although the external diameter will be larger. 

Note that PVC fittings have larger external diameters than pipes so that they can slot over the pipes. The important thing to remember is that you must always purchase the same labelled sizing for all your PVC pipes and fittings to work together (i.e., 1” pipes with 1” fittings).

If you want to use a non-PVC element in your system for whatever reason, you should check that the internal diameter of that pipe or fitting matches the PVC sizing. Other materials use different sizing systems that may not reference the internal diameters like PVC. 

Scheduling and classes

You’ll see many pipes and fittings come with a labeling for classes or scheduling. The number refers to the thickness of the pipe walls. The higher the number, the thicker the wall.

Common examples are schedule 40 and 80. Schedule 80 pipes and fittings (SCH 80) have thicker walls than SCH 40 and are better suited to heavy duty uses, such as pressurized water and underground installations. This makes them more expensive to purchase.

In theory, you can use SCH40 and SCH 80 in the same system as long as the sizing matches. However, your pipe system is only ever as strong as your weakest point. So, if you need to use SCH 80, use it for every pipe and fitting to avoid problems. If you can use SCH 40, you will save unnecessary costs by sticking to SCH40 throughout.  

You may see other initials that classify PVC. These refer to what they are suitable for. Some examples include:

• EB – encased burial in concrete
• DB – direct burial underground
• PN is a pressure rating, with a higher number indicating the ability to cope with higher pressures

Sealing

PVC pipes and fittings should fit snugly. However, they will not be watertight unless they are properly sealed at all joins. 

A lot of PVC pipes and fittings have plain or slip ends, which means they simply slip over each other. Others have a rubber ring joint within them. The rubber ring is compressed when the two fittings slot together, improving the seal. Occasionally, PVC have thread joints.

Before you embark on your project, be sure to purchase any necessary additional sealants, adhesives and primers. You should get professional advice from the PVC manufacturer or retailer as to what is appropriate for your chosen PVC system.

Need further help?

PVC pipes and fittings can seem complicated at first. Luckily, there are friendly professionals available to help. If you need any assistance with choosing a fitting, the right sight sizing or class, or the best method of sealing, be sure to get in contact with us.