7-letter, 9-letter L-shaped anchor bolt (Chinese national standard GB/T799-1988 embedded anchor screw)

1. Product application and execution standards

This product is produced in strict accordance with Chinese national standard GB/T799-1988. It is an L-shaped 7-character and 9-character pre-embedded anchor bolt. It is a special fastener for steel structure workshops, tower crane bases, street light poles, high-voltage iron towers, bridge equipment bases, and large engineering machinery infrastructure. The products have been exported to overseas infrastructure markets such as the Middle East, Southeast Asia, and Africa for a long time. They are embedded in concrete during civil pouring construction and play a key role in fixing the main body of the equipment, carrying the overall load, and resisting foundation settlement and displacement. They are indispensable embedded accessories for civil engineering projects.

2. Raw material selection and production process

The raw materials are Q235, 35cr, 45#, and 40cr high-quality round steel. The production process is: round steel blanking and cutting → high-temperature bending and forming of 7-character and 9-character hooks at one end → precision thread rollingtapping at the other end → surface anti-rust treatment. The hook is forged and bent in one piece, with no cracking or stress defects at the bend. After being embedded in the concrete, the hook is firmly engaged with the cement, giving it strong anchoring force. The thread adopts precision rolling technology, with regular tooth shape, and engages closely with the matching nut, making it difficult for the thread to slip when locked during installation.

3. Surface selection and product advantages

Conventional in stock is natural black oxide rust-proof, cost-effective, and meets the pre-embedded needs of indoor factories; hot-dip zinc plated and zinc plated anti-corrosion processes can be customized on demand. The hot-dip galvanized version has a thick zinc layer and is resistant to salt spray and outdoor acid and alkali corrosion, and is suitable for harsh environments such as the seaside, open-air wind power plants, and bridges. The L-shaped hook structure is different from straight bolts. It relies on the hook to increase the concrete bite area, has excellent pull-out resistance, and effectively avoids the risk of loosening in the future. The specification drawings, bend length, and thread section length can be modified according to the nonstandard customer construction drawings.

4. Quality inspection delivery and supporting services

M12~M48 mainstream specifications are always in stock, short sizes are shipped in stock within 48 hours, and extra-long customized models are produced according to construction schedule. The screw diameter, thread accuracy, and bending dimensions are verified before leaving the factory to eliminate dimensional deviations and defective products with incomplete threads. It can provide one-stop support for the factory's self-produced nuts, flat washers, and spring washers, and the entire package is packaged and shipped, saving customers the trouble of purchasing separately; it supports customized special-shaped anchor bolts according to the drawings, and relies on large-scale production capacity to stably undertake full-container export orders. It is the preferred product for overseas infrastructure pre-embedded procurement.