GB/T 16929-1997 specifies the test method for oil permeability of Encasement materials. The standard clarifies the principle of oil permeability determination, introduces the required equipment, such as oil permeable cups, thermostatic devices, etc. Detailed test steps, including sample preparation, test conditions setting, data recording and other links. Through standardized operation, the oil permeability performance of Encasement materials can be accurately determined, providing an important basis for the selection, research and development of Encasement materials and the estimation of product shelf life. It helps to ensure that Encasement products effectively block oil penetration during storage and circulation, and ensure product mass and Encasement integrity.