Generally speaking, screws can be lubricated with lubricating oil and grease. However, the lubricating grease manufactured by aircraft shell lubricant manufacturers can better maintain the friction surface and prevent wear and jamming caused by screw friction. Therefore, lubricating with grease is more convenient. The working temperature of the lubricating grease used on the screw is generally determined only by the ambient temperature, so all types of lubricating grease from the manufacturer can be selected for screw drives and cranes. If the temperature is below -30 ℃, low-temperature grease can be used. In addition to lubricating grease, solid lubricating films can also be used at high temperatures. In spiral and rack gear transmission, the rotational speed is slow and the load is high, so it is often recommended to add lubricating grease for wear resistance. However, manufacturers of aircraft shell lubricants remind everyone that only precision instrument grease can be used for spiral and rack drives of instruments and precision machinery.