Can the long screws be surface treated?

When we are making screws, we generally need to do some treatment on the surface of the screws, such as electrophoresis, zinc plating, nickel plating, gold plating, dacromet, and so on. This will improve the corrosion resistance of the screw, and in the appearance, it will also look better. So for long screws, can you also do the surface treatment?

Screws with a length of less than 50mm are commonly seen, and screws with a length of about 100mm are also common. However, screws with a length of more than 200mm are relatively rare, and although such a long screw can also do surface treatment, the surface treatment it can do is also limited. Because some electroplating factories because of equipment, can do the length is limited. Or some electroplating factories can do the surface treatment of such long screws, but there are not so many types of surface treatment.

And some long screws are not recommended to do surface treatment. Like a long, thin screw made of iron, this type of screw can easily bend if it is hardened and cannot be straightened after bending. This is not recommended to do hard surface treatment, direct galvanized, nickel plating, etc.