subject: Galvanization Of Lag Bolts [print this page] Lag bolts are used specifically for the wooden blocks and wooden structures. These bolts are used to fasten them securely so that there is no chance of dropping out. These galvanized bolts are usually made of carbon steel or generally also known as mild steel. These lag bolts as it is made out of mild steel are very vulnerable to atmospheric moisture. The lag bolts tend to pick up the moisture from atmosphere and gets rusted which could endanger the structure it supports.
To avoid the rusting of lag bolts those are coated with a layer of zinc coating which greatly enhances the resistance to corrosion. This galvanization is made by various processes. Those are dip process, electroplating by zinc, electroplating with chromium or nickel etc. generally the coating with zinc is taken. This is because it is cheaper to chromium and nickel. And out of the two processes of galvanization the electroplating process is chosen. This is because the work is faster and also the wastage is less. In electroplating process in the electrolytic solution the plat of zinc is dipped and also the bolts that are to be electroplated. The zinc plate is connected to the positive charge also known as anode and the bolts that are to be electroplated is connected to negative charge or cathode.
Then a specific current is passed through the circuit containing the electrolytic solution, zinc plate and the bolts those are to be plated with zinc. In the process the molecules of zinc from the plate gets carried away through the electrolytic solution and gets deposited on the cathode, the bolts which act as cathode. After certain period of process there is a thin layer of coating formed on the bolts. These, now galvanized lag bolts are then taken out and washed in clean water.
In the dip process of the bolts those are to be galvanized are dipped in the bath containing hot molten zinc. These are then taken out and kept aside for cooling. The galvanization that is done through electroplating process is superior to the one done through dip process. This is because in dip process the coating formed is thick and may vary in coating thickness and the luster on the coating is also dull. But in electroplating process the coating of zinc formed is very thin and even and also has a good luster. These bolts are then packed and sent to different customers. They either sell the galvanized bolts to direct consumers that are the end manufacturers or sold to the wholesale dealers.
These galvanized bolts come in varied sizes, such as thickness and length. The head is in the form of hexagonal or round and the length goes to few inches depending on the demand. Connected to the head is a cylindrical body with threads threaded till the end of the bolt. The lag bolts are fastened to the wood by means of spanner or a torque wrench. This is done rotating the bolt in clock wise direction with certain amount of force. The removal of the bolt is done in opposite direction.
