Expansion screws are generally referred to as metal expansion screws. Its fixing principle the fixation of expansion screws is to use wedge slope to promote expansion to generate friction grip force to achieve the fixing effect. One end of the screw is thread, with a taper on one end. The outer bread is a sheet of iron (some are steel pipes), and the half of the sheet of iron cylinder (steel pipes) has several cuts. Put them together into the hole laid on the wall, and then lock them. Nut, the nut pulls the screw out, pulls the taper into the iron cylinder, and the iron cylinder is raised, so it is tightly fixed on the wall, which is generally used for protective grating, awning, air conditioners, etc. in cement, fastening on materials such as bricks. However, its fixation is not very reliable. If the load has a large vibration, it may loosen. Therefore, it is not recommended to install ceiling fans.

II. Scope of use

shipping instructions
delivery method:
1. Yiwu customers can deliver goods to your door! (Free)
2. Delivery methods in other places are YTO, STO, ZTO, Tiantian, Yunda, and SF Express (delivery in Zhejiang, Shanghai and Jiangsu regions will arrive the next day, and Guangdong and other places will arrive 3 days at the latest)
3. Logistics companies can be designated by customers! For example, CityStar, Heaven and Earth Huayu, Debang, Hesheng... . And other freight departments (Zhejiang, Shanghai, and Jiangsu regions deliver the goods the next day) Note: When in stock, the minimum delivery is not limited.
Tips: Customers can choose logistics reasonably according to regional conditions, subject to negotiation!
For example, if there is no other explanation, the samples are delivered by SF Express by default. It takes 12-24 hours to arrive in major cities across the country. (General: 12 yuan for Zhejiang and Shanghai, 22 yuan for other provinces)
sample Description: samples can be provided free of charge, and additional proofing fees are charged for products requiring proofing.
Shipping instructions:
the above quotation does not include freight. Please contact us for specific freight. If you need to arrange it separately, the negotiation between the two parties shall prevail. Online quotation is only used as reference price, and all transactions are subject to the price agreed by both parties! Integrity guarantee, long-term cooperation! Zhejiang Hongyang Aliwangwang, No. Standard component factory
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