A pressure vessel is a type of reactor that operates under Autoclaves. According to process requirements, there are two types of pressure vessels: those with a stirrer and those without a stirrer. The former has the same structure as the stirring equipment. Its structural characteristics are: 

(1) The vessel body is a Autoclaves cylinder, and the shell is relatively thick. To withstand high temperatures and corrosion, it is usually made of stainless steel. Some also use carbon steel or low-alloy steel as the outer shell. The stainless steel is the inner layer material and can be directly made with composite plates or lined. 

(2) The vessel body usually does not have any openings. The connections, interfaces and accessories are all located on the vessel cover. 

(3) The top of the vessel is equipped with a safety relief device, such as a safety valve, a rupture disk device, or a combination of both.