The production process of zinc plated hex bolts typically involves several steps：

1. Material selection: High-quality steel is chosen as the base material for hex bolts. The steel should have the necessary mechanical properties to meet the required standards.

2. Cutting and shaping: The steel rods are cut into appropriate lengths and then shaped into the desired hexagonal bolt shape using machines like thread rolling or cold heading machines. This process ensures consistent dimensions and shapes for the bolts.

3. Threading: The bolts are then passed through a threading machine, which cuts the threads into the shank. This creates the spiral grooves that allow the bolt to be screwed into a threaded hole.

4. Heat treatment: After threading, the bolts may undergo heat treatment processes like quenching and tempering. This helps to improve their hardness, strength, and resistance to deformation.

5. Cleaning and pickling: The bolts are cleaned thoroughly to remove any dirt, oil, or other impurities from the surface. Pickling is then done to remove any rust or scale that may have formed during the previous steps.

6. Zinc plating: The bolts are immersed in a zinc plating bath, which contains a solution of zinc salts. The bolts act as the cathode, and an electric current is passed through the solution to deposit a layer of zinc onto their surface. This process is known as electroplating.

7. Passivation: After zinc plating, the bolts are treated with a passivation solution. This helps to improve the corrosion resistance of the zinc coating and enhances its durability.

8. Inspection and quality control: The zinc-plated hex bolts undergo rigorous inspection to ensure they meet the required specifications. This includes checking the dimensions, thread quality, and overall appearance.

9. Packaging: Once the bolts pass the quality control checks, they are packaged and prepared for shipment. They are typically packed in boxes or bags, with proper labeling and documentation.