How to control the splicing accuracy of profiles to avoid leakage during the processing of broken bridge aluminum alloy casement windows?
Release Time : 2026-01-22
In the manufacturing process of broken bridge aluminum alloy casement windows, the precision of profile splicing directly affects their sealing performance and leak-proof capability. If gaps or misalignments exist at the splicing points, rainwater can easily seep into the interior through capillary action, significantly increasing the risk of leakage, especially under wind pressure. Therefore, a comprehensive approach is needed, encompassing equipment precision, process control, material selection, operational procedures, and quality inspection, to ensure that the splicing precision meets design requirements.
High-precision processing equipment is a prerequisite for ensuring splicing precision. Cutting saw blades need to be replaced regularly to avoid burrs or angular deviations at the profile ends due to wear. Corner assembly machines must have a stable pressure control system to ensure a tight fit between the corner brackets and the profile cavity, minimizing gaps. Furthermore, using CNC machining centers can automate processes such as profile drilling and milling, avoiding human error and improving processing consistency. For example, during corner assembly, if the gap between the corner bracket and the profile is too large, even with subsequent sealant filling, leakage may still occur after long-term use due to sealant aging.
Process control is the core element for ensuring splicing precision. The 45-degree corner assembly process is commonly used for broken bridge aluminum alloy casement windows. The angle accuracy must be controlled within ±0.5°; otherwise, gaps are likely to appear after assembly. Specialized corner brackets must be used during processing, and their material should be similar to that of the profile to reduce loosening caused by differences in thermal expansion and contraction. The pin-injection process involves injecting specialized corner assembly adhesive into the gap between the corner bracket and the profile, forming a flexible sealing layer that fills small gaps and enhances structural strength. The impact corner process uses mechanical impact to deform the end of the profile, forming a physical lock with the corner bracket. This is suitable for high wind pressure areas, but the impact force must be strictly controlled to avoid cracking of the profile.
Material selection is crucial for splicing accuracy and leak-proof performance. The profile wall thickness must meet design requirements; too thin and it will easily deform during corner assembly, too thick and it increases processing difficulty. The thermal insulation strip material must match the profile to avoid cracking at the splice due to differences in expansion coefficients. The sealing strip should be made of EPDM rubber, which is resistant to aging and has good elasticity. Its compression set should be controlled between 20% and 30% to ensure continued sealing even after long-term use. If the strip is too hard or too soft, the seal at the joint may fail.
Proper operating procedures are crucial for ensuring splicing accuracy. Before processing, the profiles must be cleaned to remove oil, aluminum shavings, and other impurities to avoid affecting the adhesion of the corner adhesive. When assembling the corners, ensure the profile ends are aligned and the corner brackets are inserted to the same depth to avoid gaps due to misalignment. During adhesive injection, control the injection pressure and speed to ensure the adhesive fully fills the gaps without air bubbles. Insufficient adhesive can create leakage channels; excessive adhesive may overflow and contaminate the profile surface.
Quality inspection is the last line of defense for controlling splicing accuracy. After processing, the corner areas must be visually inspected to confirm the absence of cracks, burrs, and other defects. Use a feeler gauge to measure the splicing gap to ensure it is ≤0.2mm. A water spray test simulates rainwater erosion to check for leaks. For the mullion connection, it is crucial to check the screw tightening torque and sealant application to prevent leaks caused by loose connections. Furthermore, the processing equipment must be calibrated regularly to ensure its accuracy meets production requirements.
Attention to detail plays a vital role in improving splicing accuracy and leak-proof performance. The gaps between the window frame and the wall should be filled with waterproof mortar or polyurethane foam, and the outer side should be sealed with neutral silicone sealant with a thickness of ≥6mm to block rainwater penetration. A pressure equalization chamber should be installed between the window sash and the window frame, and drainage holes should be used to drain accumulated water outdoors, preventing rainwater backflow due to wind pressure differences. Allowance should be made for the compression of the rubber strip at hardware installation points to ensure the rubber strip is fully compressed when the window sash is closed, reducing the risk of leakage.
The splicing accuracy control of broken bridge aluminum alloy casement windows must be maintained throughout the entire processing. By selecting high-precision equipment, optimizing process parameters, strictly controlling material quality, standardizing operating procedures, strengthening quality inspection, and paying attention to detail, splicing accuracy can be significantly improved, effectively preventing leakage problems and ensuring the long-term stable performance of doors and windows.