If you must use the best piping made from industrial, domestic, or agricultural-grade plastic piping, the two best options that can be used at present are MDPE and HDPE pipes. At New Tech, we know that the choice you make will go a great distance in shaping the durability, functionality, and safety of your piping system.
In this comprehensive blog, we break down the primary differences between MDPE (Medium-Density Polyethylene) and HDPE (High-Density Polyethylene) pipes, so you can discover their specific characteristics, usage, and what will suit your project best.
What is Polyethylene?
Polyethylene is a thermoplastic petroleum-based polymer. It’s widely used across industries due to its excellent chemical resistance, lightweight construction, and long life. Polyethylene is classified on the basis of density and molecular weight, both of which have an effect on strength, flexibility, and pressure performance.
The most common varieties are:
- LDPE – Low-Density Polyethylene
- MDPE – Medium-Density Polyethylene
- HDPE – High-Density Polyethylene
While LDPE is mostly used in packaging, MDPE and HDPE pipes are preferred for gas and water transportation due to their better performance.
What is MDPE Pipe?
MDPE pipe is manufactured from polyethylene with a density of 0.926–0.940 g/cm³. It provides a balance between strength and flexibility and is therefore especially ideal for use in applications where ground movement or external pressures are a problem.
Typical Features of MDPE Pipes:
- Moderate strength and flexibility
- Good impact resistance
- Fine chemical resistance to corrosion
- More flexible than HDPE, but still stronger than LDPE
- Performs well at middle pressure levels
- Typical color: Gas – Yellow; Water – Blue
Typical Applications of MDPE Pipes:
- Domestic and building water supply
- Gas grid distribution
- Agricultural irrigation systems
- Protection of cables underground
- Severage and drain systems
What is HDPE Pipe?
HDPE (High-Density Polyethylene) pipe is made from polyethylene with a density of 0.941 g/cm³ or higher. It’s extremely well known for possessing a high strength-to-density ratio, thus being stiffer and stronger against high-pressure applications.
Most Important Features of HDPE Pipes:
- High tensile strength and stiffness
- Excellent resistance to UV radiation and extreme temperatures
- Very long-lasting and durable (up to 100 years)
- Ideal for high-pressure and heavy-duty applications
- Low gas and liquid permeability
- Standard colours: Black striped (blue or orange) for general use
Standard Applications of HDPE Pipes:
- Industrial and municipal water mains
- Waste disposal and sewerage systems
- Oil and gas pipeline systems
- Fire protection pipes
- Mining operations
- Marine installations
MDPE vs HDPE Pipes – The Differences:
Having established the ground work on what each one is, let us now go over the key differences between MDPE and HDPE pipes to allow you to make an informed decision.
1. Material Content and Density:
MDPE is less dense compared to HDPE, giving it greater flexibility and the capacity for dealing with bending and movement installations.
HDPE is denser and more stiff and is used in applications where strength and resistance to pressure are required.
2. Resistance to Pressure:
HDPE pipes are better equipped to deal with high pressure. That’s why they are typically used in industrial, municipal, and high-demand applications.
MDPE pipes, despite being strong, are more suited to medium-pressure applications like water supply lines and gas pipelines.
3. Flexibility and Ductility:
- MDPE pipes are less rigid than HDPE pipes and hence easier to install in locations with ground or moving soil.
- HDPE pipes are more rigid, which helps in maintaining shape under pressure but may be harder to install in tight spaces.
4. Durability and Lifespan:
- Both pipes are long-term durable, but HDPE beats the competition with respect to lifespan in harsh conditions, such as exposure to chemicals, sun rays, and heavy loads.
- MDPE remains to be strong and durable but is mostly used in underground and less challenging applications.
5. Environmental Resistance:
- Both pipes are resistant to corrosion and chemical damage, but HDPE is more resistant in exterior and sun-prone environments.
- MDPE, being softer, can be deformed at high temperatures but works effectively in regulated underground conditions.
6. Cost and Availability:
- MDPE pipes are generally cheaper for medium-scale projects.
- HDPE pipes might be costlier due to their higher strength and performance capabilities.
7. Joining Methods:
- Both can be electrofused or butt fusion-welded, but HDPE pipes require more careful handling during fusion due to their hardness.
- MDPE pipes are simpler to navigate and connect due to the fact that they are more flexible.
Choose MDPE If:
- You’re working on a residential gas or water supply installation
- Ease of installation and flexibility are significant factors
- The pipe will be underground with low pressure
Use HDPE If:
- You need a pipe for high temperature or high-pressure applications
- The pipe will be exposed to outdoor or industrial environments
- There needs to be long-term resistance to harsh conditions
Installation Considerations for MDPE and HDPE Pipes:
Regardless of the type of pipe you choose, proper installation is necessary to get maximum performance and safety.
MDPE Pipe Installation Guidelines:
- Always use proper trenching and bedding practices
- Avoid sharp curves to prevent stress cracks
- Use proper fusion equipment for flush joints
HDPE Pipe Installation Guidelines:
- Account for thermal expansion and contraction
- Use mechanical restraints where necessary in high-pressure zones
- Ensure butt fusion joints are attended to by skilled individuals for integrity
Environmentally Friendly and Recyclable:
MDPE and HDPE Sustainability:
- Both MDPE and HDPE can be recycled. We at New Tech promote environmentally friendly engineering solutions, and polyethylene pipes very much belong to that vision.
- HDPE is marginally superior since it lasts longer, thus requiring less replacements.
- MDPE is recyclable and reusable too, and thus it is a good environmentally friendly substitute for short to medium duration projects.
Last Word – MDPE or HDPE?
Both MDPE and HDPE pipes provide effective and durable solutions for gas and fluid transportation. The choice ultimately depends on your project size, environmental conditions, and performance requirements.
- Choose MDPE when flexibility, medium pressure, and lower cost are of concern.
- Choose HDPE when you require durability, high strength, and long-term resistance to environmental factors.
At New Tech, we’re committed to helping you choose the best piping solutions for your needs. From building a water distribution system to implementing an industrial pipe, being aware of material differences will lead to better performance and fewer issues down the road.
Need Expert Advice? Contact New Tech Today:
Not sure what pipe is ideal for your use? Our New Tech specialists are here to assist. With decades of experience with plastic piping solutions, we will make sure that your projects endure.
