HDPE geocell, raw material purity is one of the primary key factors affecting product performance and service life. Using high-purity, high-quality virgin materials (new materials) can significantly improve the physical and chemical properties of geocells, while using inferior recycled materials will cause a series of serious problems such as weld cracking, accelerated aging, and structural instability.
The influence of raw material purity on geocell performance
The tensile strength is obviously different; the cells made of new materials have high tensile strength, strong ductility and are not easy to break; the cells mixed with recycled materials are prone to cracking and deformation during actual laying or filling and compaction.
The welding strength is limited; the impurities and aging components in the recycled materials will cause uneven welding, resulting in "false welding" or "weld point detachment" phenomena, reducing the overall stability of the cell.
The weather resistance drops sharply; the new materials are added with anti-UV and antioxidants, and the service life can reach more than 20 years; while the recycled materials lack these additives or the content is insufficient, and they may age and crack after 1-3 years of outdoor use.
The safety and environmental protection performance is worrying; inferior recycled materials often contain heavy metal residues and toxic gas release risks, posing a threat to groundwater and the ecological environment, and do not meet environmental protection standards.
Why is HDPE geocell welding strength so important ?
Structural stability core; The honeycomb structure of the HDPE cells must be connected by welding points. If the welding points are not firm, even if the raw materials are of high quality, a stable overall structure cannot be formed.
Engineering load requirements; In projects such as roadbed reinforcement, slope protection, and dam support, welding points must withstand repeated stretching and compression from fillers, deadweight, and vehicle loads.
Durable life guarantee; Poor quality welding is prone to breakage under ultraviolet radiation or temperature changes, affecting the long-term performance of the product and even causing structural collapse.
Common welding methods
Ultrasonic welding: High-frequency vibration causes the material interface to melt and solidify instantly. It is characterized by fast welding speed and high consistency of weld points, and is widely used in high-end products.
Hot-melt welding: Use an electric heating device to locally heat the HDPE sheet to the melting point before bonding. The cost is low, but the temperature and pressure need to be strictly controlled.
How to judge welding quality?
Tensile test (peel strength test)
According to GB/T 19274 or ASTM standard, the peel strength of high-quality welds should generally be greater than 10N/cm, and some can reach 15-20N/cm or more.
On-site tear test
Cut off some cells from the finished product, tear the welds manually to observe the fracture position.
High-quality products: fracture occurs in the HDPE strip body;
Low-quality products: fracture occurs at the weld, indicating that the welding is not strong.
Observe the appearance of the weld
Good weld: uniform color, full surface, no charring, no convex scar;
Bad weld: rough edge, lack of glue, inconsistent color, weld void.
Purchase suggestions: Check the following points to determine the quality of solder joints
Choose products that use ultrasonic welding, which have high welding consistency;
Request a welding strength test report to see if it meets national or industry standards;
Require samples to undergo actual tearing tests;
Investigate production line equipment and process flow on site;
Give priority to mature brand manufacturers with engineering case support.
