M4 M16 Carbon steel L & J Hook metal Bolt with nut washer Class4. grade 8.8 Yellow plating

• Fixed Footbolt: Poured with foundation for equipment without strong vibration/shock
• Activity Footbolt: Removable type for heavy machinery with vibration/shock
• Expansion Anchor Bolt: For static/simple equipment with specific installation requirements
• Bonding Anchor Bolt: Common modern solution with standard installation methods

For loose bolts: weld reinforcement bars around bolt, clean and grout. For bolt deviations: adjust position, cut/extend as needed, or use bending method for correction.

J-bolt (also called J-anchor, J-bolt) = a straight rod + 180° curved hook, shaped like a capital J. It has no expansion piece and is not filled with glue.
It does not have its own expansion piece, not filled with glue, and relies on the "hook" buried in the concrete to eat the pull-out force. Core features in 8 sentences:
Single hook anchorage
The inside of the hook bites into the concrete and provides a purely mechanical locking key, which is reliable without glue.
Resistant to pullout but not to shear
The design specification puts the "hook" as a tensile anchor, the lateral shear force depends on the friction of the base plate or another shear key, don't expect it to carry a single shear.
Specification ceiling
Hooks need to be hot bending, ≥ M39 Heating zone strength loss, the standard recommended maximum to M36, grade commonly used 4.6 / 5.6.
Depth of burial = lifeline
Minimum depth of burial 12 d (d = diameter of the rod) or 6 times the straight section of the hook, otherwise the pull-out test will fail in minutes.

Suitable for equipment fixing, steel structure foundations, street lamps, traffic signs, pumps, boiler installation, and heavy equipment pre-embedded fixing.