What is the purpose of using emery cloth on plunger surfaces?

Using emery cloth on plunger surfaces primarily serves the purpose of cleaning. Emery cloth is an abrasive material that can effectively remove contaminants, corrosion, and any buildup of dirt or debris from the surface of the plunger. This cleaning ensures that the plunger operates smoothly and maintains good contact with adjacent components, which is essential for the proper functioning of jacks.

While polishing can be a result of using emery cloth, the main objective in this context is to prepare the plunger surface by clearing it of unwanted material rather than focusing on achieving a polished finish. Strengthening and coating are not relevant purposes for using emery cloth, as it is not designed to enhance the material properties or add layers to the plunger surface. Overall, the emphasis on cleaning highlights the importance of maintaining equipment for safe and efficient operation.