哈德沃角码

You can judge whether door and window anti-fall chains needs to be replaced through the following signs:

- Appearance inspection: The chain is obviously deformed, cracked or broken; the connecting piece has welding points falling off or rust perforation; the screws are severely rusted and cannot be tightened.

- Function test: Jamming or abnormal noise occurs when pulling the chain; when the door/window is opened to the maximum angle, the chain is obviously stretched and lengthened (more than 5% of the original length); the chain is bent and deformed after bearing weight (cannot return to its original shape).

- Service life: If it reaches or exceeds the average service life of the material (such as zinc alloy for more than 3 years, stainless steel for more than 8 years), even if the appearance is normal, it is recommended to replace it (metal fatigue may cause hidden damage).

- Environmental impact: After extreme weather such as typhoons and earthquakes, a comprehensive inspection is required. Even if there is slight deformation, it is recommended to replace it to avoid potential risks.