How to Make uPVC Window Door
Part 4 Reinforcement Steel Cutting and Installation
How to make a uPVC window door? This is the 4th part to introduce reinforcement steel cutting and installation.
1. The function of the reinforcement steel
- Firstly, improve the rigidity and strength of uPVC windows and doors.
- Secondly, prevent profile deformation.
- Moreover, make the hardware installation more solid.
2. The technical requirement for the reinforcement steel
1) Material and Thickness
Made by the cold rolling Q235 steel strip.
The surface is also treated by anti-corrosion or zinc plating to prevent corrosion.
Normally the thickness is 1.2mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm.
The suggestion using thickness is ≥1.5mm.
Moreover, the thickness of the reinforcement should also accord the window door size, location to choose.
2) The reinforcement steel size and shape
This reinforcement steel is installed inside the profile’s main cavity.
The matching gap between the reinforcement steel and uPVC profiles‘ main cavity is 1±0.5mm.
This gap makes installation easier to restore after the window pressure.
Meanwhile, reinforcement steel dimension tolerance is ±0.1~0.5mm.
And the shape should according to the profile cavity, type and hardware installation to design.
Normally they have below shape.
3) The reinforcement steel appearance
- Firstly, the inside and outside surface should smooth. The cracks, delamination and lap welding defects are not allowed.
- secondly, the both ends of the reinforcement steel cutting inclination should less than 7 degree. It should be smooth and burr-free.
3. Installation principles
Suggest all the profile install the reinforcement steel.
Some situations below must install reinforcement steel.
- After window pressure calculation, the frame, sash, and mullion could not reach the security value.
- If using self-drilling screw to fix the hardware in frame, sash and mullion, we must use the reinforcement steel. This could ensure the necessary fastness of the hardware.
4. Reinforcement steel cutting
It should use belt saw, toothless saw to cutting.
Both ends cutting angle suggests 45 degrees and tolerance ±1°.
The minimum vertical distance from the steel to the profile end is 5~10mm. this could ensure the hardware fixed on the steel. Enhance the hardware fastness.
After that cutting, it must be corrected. Keep the ends burr-free.
The straightness accuracy should less than 1.5mm for each linear meter.
Twisting degree should also less than 1 degree.
Angular deviation tolerance ±1.5°.
Inside radius is not more that 1.4-time thickness.
5. Reinforcement steel installation
- Firstly, If this not affect the welding, it could be inserted in advance.
- Secondly, for 十type or T type, after welding this part then insert steel
We should also use self-tapping screw and self-drilling screw. Core-pulling rivets are prohibited.
The screw for each length steel fastness should more than 3pcs.
Meanwhile the distance between two screws ≤300mm. The distance between the screw and profile end should also ≤100mm. After that fixed, the steel should not be loose.
After that inserting the steel, we should ensure the profile cavity no scratches, deformation and also not affect the hardware installation.
Moreover, if the steel size not match the profile cavity, we should not insert the steel by force.