Detailed explanation of corner assembly technology for casement windows
The corner-collision technology of casement windows is a key process in the processing of aluminum alloy doors and windows, and is mainly used for connecting the four corners of window frames. The core is to use special equipment to accurately cut, stamp and assemble the profiles to achieve high-strength and high-sealing corner connections. The following is a detailed analysis of the technology:
Principle of corner-collision technology
Definition
The corners of the profiles are extruded and spliced through hydraulic or electric corner-collision machines, and the two sections of the profiles are firmly connected at a 90° angle by using the combination of corner codes and corner glue.
Core components
Corner code: usually made of aluminum alloy or nylon, with teeth or threads to enhance mechanical bite force
Corner glue (sealant): fill the gap between the profile and the corner code to improve sealing and seismic resistance
Ring: drive the corner code hole during corner collating to tightly fix the profile and the corner code
Process flow
Profile cutting
Use a double-headed saw to cut at a 45° angle to ensure that the cross section is flat and burr-free (tolerance must be ≤0.1mm)
End milling
Mill the end face of the profile to reserve space for the corner code installation
Corner code installation
Insert the corner code into the profile cavity and apply corner glue (such as polyurethane glue) on the contact surface
Corner machine crimping
Use the punch of the corner machine to squeeze the corner of the profile, and the nail penetrates the profile wall and locks the corner code
Cleaning and inspection
Remove the overflowed colloid and check the strength of the corner (common test: diagonal tensile force ≥ 2000N)
Technical advantages
High strength
The mechanical connection of the corner + corner code is more resistant to wind pressure than simple screw fixing (up to level 9 wind pressure resistance performance)
Good sealing
The corner glue fills the gap and effectively prevents rainwater penetration (water tightness ≥ 500Pa)
Aesthetics
There are no exposed screws at the corners, and the surface is flat
Key quality control points
Profile accuracy
Cutting angle error must be controlled within ±0.5°, otherwise it will cause angle misalignment.
Glue selection
Highly elastic angle glue (such as German Weishi glue) should be used to avoid cracking after long-term use
Equipment calibration
The punch pressure of the angle machine (usually 15-20MPa) needs to be checked regularly to prevent overpressure from causing profile deformation
Common problems and solutions
Problem 1: Corner cracking
Reason: The angle glue is not cured or the rivet is too deep.
Solution: Adjust the glue curing time (it is recommended to move after 24 hours) and control the depth of the rivet.
Problem 2: The window frame is not flat after the angle is assembled
Reason: The profile cutting is not vertical or the positioning of the angle machine is biased
Solution: Check the verticality of the saw blade and use a positioning fixture to assist in assembly
Comparison with other corner assembly technologies
Technology Corner assembly Active corner code Pin injection
Strength High Medium Very high
Sealing Excellent Average Excellent (injection filling)
Cost Medium (special equipment required) Low High (complex process)
Application suggestions
Recommended scenarios: high-rise buildings, coastal windy areas and other environments with high requirements for sealing and strength
Equipment selection: Preferentially select corner assembly machines with CNC systems (such as Yelu and Yimeiji brands) to ensure pressure accuracy
Through standardized operation and strict quality inspection, corner assembly technology can significantly improve the performance and life of casement windows