Drill collars are heavy, thick-walled tubes used in the drilling process of oil and gas wells. They are placed below the drill bit to provide weight and stability, helping to maintain contact with the rock formation. This added weight enhances the drilling efficiency and allows for deeper penetration into the earth. Typically made from steel, drill collars come in various lengths and diameters to suit different drilling needs. Their design helps to counteract the forces that can cause the drill string to bend or break, ensuring a smoother drilling operation. Proper use of drill collars is essential for successful drilling in challenging environments.