What Are the Common Quality Issues of Polyamide Thermal Break Strips and How to Avoid Them?

As a thermal break strip manufacturer with R&D experience since 2006, we understand that even small quality flaws in polyamide thermal break strips can destroy their thermal insulation function. Poor quality strips not only fail to block heat transfer but also increase maintenance costs for window and door manufacturers. Through our one stop service—covering raw material production, extrusion equipment and technical support—we help customers identify and avoid common quality issues, ensuring every thermal break strip meets high performance standards.

Why Quality Matters for Polyamide Thermal Break Strips

The Link Between Quality and Thermal Break Performance

Polyamide thermal break strips are the core of aluminum window thermal insulation systems. A strip with quality defects (like cracks or uneven thickness) creates gaps between aluminum profiles, letting heat pass through and reducing the overall thermal break effect by 40% or more. For example, a strip with surface bubbles traps air, which conducts heat faster than solid polyamide. In cold climates, this means higher heating bills; in hot areas, more energy is used for cooling. High quality thermal break strips are not just a product—they are an investment in long term energy efficiency.

Risks of Poor Quality for Manufacturers

Window manufacturers that use low quality thermal break strips face serious risks. Defective strips often break during installation, leading to rework and delayed projects. Even if installed, they degrade quickly—after 2-3 years, cracks may form, forcing manufacturers to honor warranties and replace entire window frames. As a one stop service provider, we know that preventing quality issues is far cheaper than fixing them later. Our solutions focus on root causes, not just temporary fixes.

Common Quality Issues of Polyamide Thermal Break Strips and Their Causes

Dimensional Deviations

Thermal break strips need precise dimensions (thickness 1.5-3mm, width 10-30mm) to fit aluminum profiles. Dimensional deviations—like inconsistent thickness or wavy edges—happen for two main reasons. First, mismatched extrusion equipment: using twin screw extruders (which are only for granulation, not strip production) leads to unstable output, as twin screws cannot control extrusion speed for strip shaping. Second, poor die design or rolling machine misalignment—if the extrusion die’s flow channel is uneven, the strip will be thicker in some areas; if the rolling machine’s rolls are not parallel, edges become wavy.

Low Mechanical Strength

A thermal break strip with low strength breaks easily during installation or use. This issue stems from two key factors. One is low quality granules: if granulation does not disperse glass fibers evenly, the strip has weak spots. The other is improper extrusion or rolling—overheating polyamide degrades its molecular structure, while excessive rolling pressure breaks glass fibers, reducing the strip’s tensile strength. For example, a strip with uneven fiber distribution may have a tensile strength of only 50MPa, far below the 80MPa standard for effective thermal break use.

How to Avoid Quality Issues with Our Solutions

High Quality Granules from Twin Screw Extruders

The foundation of quality thermal break strips is good granules—and our twin screw extruders ensure this. Twin screws work together to disperse glass fibers into polyamide evenly, forming a strong network structure. This uniform distribution eliminates surface bumps and boosts strength—our granules have a fiber dispersion rate of over 95%, ensuring the final strip has consistent strength (tensile strength ≥82MPa). We also dry granules to a moisture content of ≤0.1% before extrusion, preventing bubbles. As part of our one stop service, we supply these granules directly to customers, avoiding the risk of low quality third party materials.

Single Screw Extruders for Stable Strip Production

Remember: only single screw extruders can produce polyamide thermal break strips. Our custom single screw extruders have precise speed control (2-5m/min) and multi zone temperature regulation (230-250°C), ensuring stable extrusion. The extruders work with our optimized extrusion dies—with symmetrical flow channels and adjustable die lips—to produce strips with dimensional accuracy of ±0.05mm. We also match each extruder with a precision rolling machine (with heated rolls and servo guides) to correct minor deviations, ensuring the strip’s flatness and dimensions meet standards. This equipment combination eliminates dimensional issues caused by wrong machines or misalignment.

One Stop Technical Support and Quality Control

Our one stop service goes beyond supplying equipment and materials—we provide full technical support to avoid quality issues. We send engineers to customers’ sites to set up production lines: calibrating extrusion dies, aligning rolling machines and training workers on parameter adjustment (like setting extrusion temperature based on ambient humidity). We also offer quality testing tools: laser profilometers for dimensional checks, tensile testers for strength tests and moisture meters for granule checks. For ongoing production, we conduct regular audits—if a customer notices surface defects, we help identify the cause (e.g., contaminated granules) and provide solutions (e.g., adding a granule filter). This end to end support ensures consistent quality.

For thermal break strip manufacturers, avoiding quality issues means protecting their reputation and ensuring their products deliver effective thermal insulation. Our combination of twin screw granulation, single screw extrusion, precision rolling machines and one stop service provides a complete solution to these problems. With 17 years of industry experience, we know what it takes to produce high quality polyamide thermal break strips—and we pass this knowledge to our customers through every part of our service.