With the development of the industry and the market’s increasing demands for equipment, door and window machines have evolved from basic models to today’s CNC, intelligent systems, and even automated production lines. The benefit of this evolution is that customers can now choose equipment based on their budget and production volume.
For small-scale factories with an annual output of 30,000–50,000 square meters, basic equipment is sufficient. This typically includes a double-head precision cutting saw, copy milling machine, punching machine, single-head corner crimping machine, and an automatic end milling machine for mullions. Depending on budget, an automatic corner connector cutting saw can also be considered. These machines are generally enough to support the required production capacity.
For larger projects with sufficient budgets, investing in CNC equipment is advisable. Available options on the market include:
- Aluminum profile cutting centers
- CNC double-head cutting saws
- Three-axis variable-angle cutting saws
- CNC drilling and milling machines
- CNC end milling centers
- CNC copy-routing machines
- Fully automatic CNC four-head corner crimping machines
- Automatic glass bead CNC cutting saws, etc.
General Workflow in a Door and Window Factory
A typical door and window production line can be broken into three major stages: cutting, processing, and assembly.
1. Profile Cutting
Cutting is the first and most crucial step in aluminum door and window manufacturing. The main equipment involved includes double-head saws, single-head saws, and automatic saws. Each tool serves different types of profiles—don’t use a sledgehammer to crack a nut:
- Double-head saws are used for cutting frames, sashes, and mullions.
- Single-head saws are used for cutting glazing beads.
- Automatic saws are used for cutting corner connectors.
The cutting length must be determined according to design specifications and technical drawings. Precision is critical, as inaccurate cuts will compromise the squareness and overall quality of the frames and sashes.
Double-head saws can cut aluminum profiles at fixed angles (commonly 45° and 90°) with high accuracy and clean cuts.
Single-head saws require two cuts to process one profile, making them less efficient.
Automatic saws (for corner connectors) are equipped with digital feed control for high precision and efficiency.
2. Drilling and Milling
After cutting, profiles require drilling, milling, and punching for several purposes:
- Joints (corner and T/cross connections)
- Hardware installation (e.g., handle holes)
- Drainage (drain holes, pressure balance holes)
- Structural assembly (installation and process holes)
Common equipment includes:
- Punching machines for drain holes, handle holes, linkage holes, and corner cleaning; suitable for square, rectangular, and round holes. They’re less effective for larger holes due to limited punching force.
- End milling machines for processing profile ends to enable proper fitting and T/cross connections.
- Copy-routing machines for milling drain holes and lock holes. These use templates and can produce various shapes (square, round, oval, figure-eight). They offer high precision and speed but are relatively expensive.
- Multi-head drilling machines and drilling-milling machines are ideal for frame processing. Adjustable head positions and fine-tunable feed rates ensure precision and versatility.
This stage involves numerous tools and demands high operator skill and equipment accuracy. Even minor errors in each step can accumulate and significantly affect final window performance. Is there a better solution? Yes: CNC machining centers.
Many factories are now upgrading from traditional tools to CNC machining centers, which offer comprehensive processing (holes, slots, end milling, cutting, etc.) all controlled by computer programming. These systems reduce reliance on skilled labor while improving accuracy and efficiency. In the future, CNC machining centers will likely become mainstream in the industry.
3. Frame and Sash Assembly
After cutting and processing, profiles are assembled into operable sash frames and fixed frames using corner connectors and other fasteners. Accessories such as sealing strips, drainage caps, and frame adjusters are installed, and sashes are connected to the fixed frame with hardware components. The products are then quality-inspected and packaged.
The only remaining step is glass installation, which is usually done on-site to avoid breakage during transport. At this point, factory-based production is complete.
The design and processing of aluminum windows and doors are equally critical and inseparable from one another. The manufacturing process is like a barrel—its performance is only as strong as its weakest part. As the saying goes, “To do a good job, one must first sharpen one’s tools.” Selecting the right equipment is crucial for enhancing efficiency and product quality in window and door manufacturing.