Correct piping is an important part of any agricultural irrigation system, from large scale industrial setups to smaller rural farms. Among farms of all sizes, rural poly pipe has become a standard for effective irrigation. Knowing how to properly install rural poly pipe and fittings is essential in avoiding leaks, burst pipes and patches of dead crops.
Rural poly pipe fittings can connect two poly pipes by unscrewing the fitting, inserting the poly pipe, and tightening the fitting with a wrench. The flexible polyethylene that makes up the pipe allows you to bend and bury the pipe to easily water your plants no matter the size or layout of your land.
We have created a short guide for those who want to understand the ins and outs of rural poly pipe, from sizes to rural poly fittings and how to use them. Continue reading to learn more.
Table of Contents
What Is Rural Poly Pipe?
Rural poly pipes are an old standard for pipes used in agricultural applications — irrigators and farmers are among its principal users. They are made of flexible polyethylene designed to withstand pressure that allows them to be laid following the contours of the earth, or bend around obstacles.
Rural poly pipes are also made to withstand geological vibrations and movements, natural temperature changes, and degradation from Ultra Violet (UV) rays through an included carbon black in the polyethylene material. This makes rural poly pipes suitable for any agricultural environment, even when exposed to direct sunlight.
Much like components in other industries, rural poly pipes come in different variations;
- Rural Poly Pipe (Green Line) – this variation is rated to withstand a maximum pressure of 800 kilopascals (kPa).
- Rural Poly Pipe (Red Line) – this variation is made to conform to AS 2698.2-2000 (Australian Standard for plastic pipes in rural applications) and is rated to withstand a little more pressure at 900 kilopascals (kPa).
What Is Rural Poly Pipe Used For?
Rural poly pipes are weather-resistant pipes that are primarily used in industrial agriculture, however their versatile design makes them a popular choice for rural irrigation, and utilities such as gas, electrical and communication ducts, and water service connections.
Rural poly pipes are known for their corrosion and chemical resistance, fatigue and stress resistance, as well as their incredibly long life expectancy. These pipes are also preferred because of their low repair frequency and adaptability in different piping systems.
Rural Poly Pipe Size Chart
For detailed technical specifications for rural poly pipe, refer to the rural poly pipe size chart below:
| Size of Pipe | Diameter (mm) Approximate Outside Diameter (OD) | Nominal Diameter (mm) | Diameter (mm) Approximate Inside Diameter (ID) | Average Wall Thickness (mm) |
| ¾” Green Line | 22.2 | 20 | 19 | 1.6 |
| 1” Green Line | 28.7 | 25 | 25.3 | 1.7 |
| 1 ¼” Green Line | 35.6 | 32 | 31.6 | 2 |
| 1 ½” Green Line | 42.8 | 40 | 38 | 2.4 |
| 2” Green Line | 57.3 | 50 | 50.9 | 3.2 |
| ¾” Red Line | 22.6 | 20 | 19 | 1.8 |
| 1” Red Line | 29.1 | 25 | 25.3 | 1.9 |
| 1 ¼” Red Line | 36.2 | 32 | 31.6 | 2.3 |
| 1 ½” Red Line | 43.4 | 40 | 38 | 2.7 |
| 2” Red Line | 57.9 | 50 | 50.9 | 3.5 |
How is Rural Poly Pipe Measured?
Rural poly pipes are measured by their inner diameter, while metric poly pipes are measured by their outside diameter. Rural poly pipe sizes can be misleading, as their sizing designations do not represent their physical measurements.
What Size Rural Poly Pipe Do I Need?
For the majority of domestic applications, a 19mm rural poly pipe would suffice. However, the right rural poly pipe size would depend on the application. The main considerations should be friction reduction and maximum flow rate and unhindered flow.
For working environments that are larger in scope, it’s ideal to use rural poly pipes that are 25mm thick. The larger size enables a larger and stronger flow, which is useful for irrigation zones that would require the pipes to run as long as thirty metres.
For high pressure application, it’s best to use 50mm rural poly pipe. This thickness of pipe is rugged and designed to withstand high water pressures.
Which Type of Fittings Are Used For Rural Poly Pipe?
Rural poly pipes have a multitude of compatible fittings — such as T-shaped, elbow, and FI adaptors. Below is a list of rural poly pipe fittings:
- Rural Poly Tee (T-shaped Fitting)
- Rural Poly FI Tee
- Rural Poly Elbow
- Rural Poly FI Elbow
- Rural Poly FI Adaptor
- Rural Poly MI Adaptor
- Rural Poly Coupling
- Rural Poly Reducing Coupling
- Rural Poly Tapping Saddle
- Rural Poly Telescopic Coupling
- Rural Poly Slipfit Coupling
- Metric to Rural Conversion Nut
These fittings come in a variety of sizes, from two centimetres up to five centimetres. The MI and FI designations refer to Male and Female threads, respectively. The fittings may either come with threads or O-rings to seal the connection. Fittings that do not have an O-ring will require the use of Teflon tape.
How Do You Join Two Pieces Of Rural Poly Pipe?
To join two pieces of rural poly pipes, you would need a rural poly pipe fitting to properly join the pipes. The process of joining those pipes is to:
- Determine the size – the very first thing you need to do is determine the size of your poly pipes. This will determine the size of the rural poly pipe fitting that should be used.
- Choose the fitting – after determining the right size, you will then have to choose the type of fitting for the application. Although rural poly pipes are known for their durability and flexibility, you would not want to bend your pipes too much. Doing so will either reduce the pipe’s life expectancy, cause leakage, or restrict the flow. Pipes that meet perpendicularly could use an elbow or t-shaped fitting. For those that meet straight into each other, rural poly couplings are appropriate.
- Inspect the seal – rural poly pipe fittings are equipped with either threads or O-rings. Whichever of the two is present in your fitting will determine whether you need to use Teflon tape. Threaded fittings will have to be wrapped with Teflon or PTFE tape, while those with O-rings do not.
- Connect the pipes – connect one of the rural poly pipes onto the chosen fitting and tighten until it no longer moves. Do the same for the other poly pipe. Once both pipes are secured, you may use a wrench to further tighten the connection.
Keep in mind that the steps listed above are general and don’t necessarily apply to every rural poly pipe connection. Different sized poly pipes and fittings may require individual procedures.
How Do You Fit Rural Poly Pipe Fittings?
There are several ways to fit rural poly pipe fittings. Although rural poly pipe fittings usually conform to Australian standards, the exact process may vary. To properly fit a rural poly pipe fitting, follow these steps:
- Insert the nut onto one of the rural poly pipes with the smaller end pointing towards the pipe and the larger, threaded end pointing outward.
- Insert the grip ring onto the same rural poly pipe, with the smaller diameter opening facing the pipe, and the larger diameter opening facing outwards.
- Take the poly insert and slide it inside the same poly pipe. You may need to use a tool to push it further in. However, make sure that you aren’t using any tool that may damage the insert (such as hammers). Once the flange hits the tip of the poly pipe, you can proceed to the next step.
- Slide the grip ring and the nut onto the flange of the poly insert. Take the central fitting and slide it onto the same poly pipe and slowly tighten the nut. This tightening process will push the grip ring onto the central fitting and seal the pipe through its O-ring.
- Repeat the same process on the other poly pipe. After the nut has been tightened, use a wrench to further tighten the nuts.
Do I Use Teflon Tape For Rural Poly Pipe?
When two threaded fittings on rural poly pipe are being connected, Teflon tape is required. However, when one or both of the fittings has an O-ring, Teflon tape should not be used. This is because Teflon may interfere with the seal created by the O-ring and cause leaks.
When applying Teflon tape to rural poly pipe fittings, the amount of tape to be used will vary depending on the application. If you are expecting the pipe to be under constant pressure, wrapping Teflon around twenty times is sufficient. For applications that do not place the pipes under constant pressure (such as irrigation risers), wrapping Teflon two to three times is enough.
How Deep Should I Bury Rural Poly Pipe?
For most applications, twenty to thirty centimetres deep is the right depth to bury rural poly pipe. However, there is no set rule for how deep rural poly pipes should be buried. The pipes should be given enough room, especially for irrigation applications where they run under the sprinklers.
Related Questions
How Do You Tighten Rural Poly Pipe Fittings?
Rural poly pipe fittings are tightened by screwing the nut of the fittings until it no longer moves. The seal can be improved further by using one wrench to hold the pipe, and another to tighten the nut.
Can You Use Compression Fittings on Poly Pipe?
Yes, you can use compression fittings such as Philmac rural compression fittings on rural poly pipe. Compression fittings are often used when the poly pipes are buried. Learn how to use Philmac 3G rural fittings here.
Disclaimer:
This article is published for general informational purposes only and does not constitute professional advice. Any action you take upon the information you find on this website is strictly at your own risk. Always ensure you have the right qualifications and certifications to carry out DIY work and never put your safety at risk. Hills Irrigation recommends consulting a professional for all electrical and plumbing work.
Vince is Managing Director of Hills Irrigation and is supported by Lisa in an administrative capacity. Andrew, Isaac and Megan look after the day to day needs of both online and shop customers. As Project Manager, Vince is also responsible for installation projects along with his team. It is his responsibility to work closely with clients to ensure that scope of work is understood and followed.
