How to test the impact resistance of PEX EVOH Pipe?

Hey there! I'm a supplier of PEX EVOH pipes, and today I wanna talk about how to test the impact resistance of these pipes. PEX EVOH pipes are super popular in the plumbing industry because of their excellent performance, but ensuring their impact resistance is crucial for their real - world use.

Why Impact Resistance Testing Matters

Before we dive into the testing methods, let's understand why impact resistance testing is so important. PEX EVOH pipes are used in a variety of settings, from residential plumbing to industrial applications. During installation, they might get dropped, bumped, or hit by tools. In the long - term use, external factors like freezing temperatures can also increase the risk of impact damage. If a pipe fails due to an impact, it can lead to leaks, water damage, and costly repairs. So, by testing the impact resistance, we can make sure our pipes can withstand these real - life situations.

Types of Impact Resistance Tests

Drop Impact Test

The drop impact test is one of the most common methods to evaluate the impact resistance of PEX EVOH pipes. Here's how it works:

First, you need to prepare the test specimens. Cut the PEX EVOH pipes into small sections of a specific length, usually around 100 - 150 mm. Make sure the ends of the specimens are smooth and free from any defects.

Next, set up the testing equipment. You'll need a drop tower, which consists of a vertical guide rail and a weight. The weight can be adjusted according to the test requirements. Place the test specimen on a rigid base at the bottom of the drop tower.

Now, it's time to perform the test. Lift the weight to a certain height, which is determined by the standard or the specific requirements of the test. Then, release the weight so that it drops onto the center of the test specimen. After the impact, inspect the specimen for any visible cracks, fractures, or other damage.

You can repeat the test with multiple specimens at different heights and weights to get a comprehensive understanding of the pipe's impact resistance. The higher the weight and the greater the height from which it drops, the more severe the impact. If the pipe can withstand these impacts without significant damage, it indicates good impact resistance.

Pendulum Impact Test

Another popular test method is the pendulum impact test. This test is based on the principle of a swinging pendulum hitting the test specimen.

To start, prepare the test specimens in the same way as for the drop impact test. Then, install the specimen in a special fixture that holds it firmly during the test.

The pendulum impact tester consists of a pendulum with a striking head. The pendulum is released from a certain angle, and as it swings down, the striking head hits the test specimen. The energy absorbed by the specimen during the impact is measured by the tester.

The advantage of the pendulum impact test is that it can simulate a more dynamic and rapid impact, which is similar to the impacts that pipes might experience in real - world situations. By measuring the energy absorbed by the specimen, we can quantify the pipe's ability to resist impact. A higher energy absorption value means better impact resistance.

Factors Affecting Impact Resistance

Material Properties

The material composition of PEX EVOH pipes plays a significant role in their impact resistance. PEX (cross - linked polyethylene) provides flexibility and toughness, while EVOH (ethylene - vinyl alcohol copolymer) acts as a barrier layer that enhances the pipe's resistance to oxygen and other gases.

The degree of cross - linking in PEX can affect the pipe's mechanical properties. A higher degree of cross - linking generally results in better impact resistance, as it makes the material more rigid and less likely to deform under impact.

The quality and thickness of the EVOH layer also matter. A thicker and higher - quality EVOH layer can improve the overall performance of the pipe, including its impact resistance.

Temperature

Temperature has a significant influence on the impact resistance of PEX EVOH pipes. At low temperatures, the material becomes more brittle, which means it is more likely to crack or fracture under impact. On the other hand, at high temperatures, the material may become softer and more deformable, which can also affect its ability to resist impact.

When conducting impact resistance tests, it's important to control the temperature of the test environment. Most standards specify a test temperature, usually around 23°C (73°F). However, in real - world applications, pipes may be exposed to a wide range of temperatures. So, it's also a good idea to perform additional tests at different temperatures to evaluate the pipe's performance under various conditions.

Pipe Dimensions

The dimensions of the pipe, such as its diameter and wall thickness, can also affect its impact resistance. Generally, pipes with a larger diameter and a thicker wall are more resistant to impact. This is because a larger diameter provides more surface area to distribute the impact force, and a thicker wall can better withstand the stress caused by the impact.

Real - World Applications and Our PE-Xa/EVOH Pipe

In real - world plumbing applications, our PEX EVOH pipes are used in both hot and cold water systems. They are also suitable for underfloor heating systems, where they need to withstand the pressure and movement associated with the installation and operation of the system.

Our PE-Xa/EVOH Pipe has been rigorously tested using the methods I've described above. We ensure that our pipes can withstand the impacts they are likely to encounter during installation and use. Whether it's a small - scale residential project or a large - scale industrial installation, our pipes offer reliable performance and excellent impact resistance.

Conclusion

Testing the impact resistance of PEX EVOH pipes is essential to ensure their quality and reliability. By using methods like the drop impact test and the pendulum impact test, we can accurately evaluate the pipe's ability to withstand impacts. Factors such as material properties, temperature, and pipe dimensions also play important roles in determining the impact resistance.

If you're in the market for high - quality PEX EVOH pipes with excellent impact resistance, don't hesitate to contact us for a purchase negotiation. We're always ready to provide you with the best products and services.

References

1. ASTM International. (Year). Standard test methods for impact resistance of thermoplastic pipes and fittings by means of a tup (falling weight).
2. ISO (International Organization for Standardization). (Year). Plastics - Determination of Charpy impact properties.