Analysis of volume increase of pressure vessel

With the increase of the scale of petrochemical plant, the volume of the container increases, the pressure vessel is more and more in the field assembly welding, and the blocking of the large diameter nozzle on the container is the difficult point of pressure test.

According to the current standard of the container is discussed, the container test pressure vessel nozzle plugging head form, and discusses the head wall thickness calculation and reinforcement with flat cover wall thickness, strengthen the calculation method of reinforcement and thickness. The structure of the test pressure blind plate is mainly in the form of the structure of the test pressure head and the blind plate. According to the connection form can be divided into butt weld connection, fillet weld connection and bolt connection. Here we focus on plugging tower container large diameter nozzle, the characteristics of the large tower site welding is the test pressure is generally not high, but because of the take over larger diameter, such as the Fushun vacuum tower oil line pipe, if the conventional calculation, selection of the blind plate thickness is very thick, which due to the direct takeover connected with other pipelines or equipment design institute did not consider the field pressure testing materials, construction units are designed.

In recent years, the construction of the accumulation, we choose the elliptical head or with the strengthening of the flat head cover, and achieved good results. The design selection of common head, the general situation of the elliptical head, we have chosen standard elliptical head. This form is suitable for low pressure and small diameter.

 But it is often used in construction and production. The fixed method we choose is connected with the nozzle angle welding. The calculated thickness for the nozzle is the effective thickness of the nozzle. According to this formula, the Fushun pressure relief tower, for example, because the site does not have the thickness of the steel plate, in addition to the economic point of view is not feasible, resulting in the following with the strengthening of the design. Ribbed flat cover reinforced by rectangular section reinforced fillet weld should adopt double continuous welding between the ribs and the flat cover; in order to meet the requirements of rib plate welding, flat cover central ring stiffener, stiffened plate between the pressure vessel sector segmentation of large diameter nozzle selection and design of pressure test blind plate. And discusses the calculation method of the thickness and the thickness of the wall thickness of the head of the flat head with ribs. The method calculates the blind plate safety, economy, construction of the Fushun and Qinzhou projects in the construction of the oil seven companies to get practical application verification, to achieve the desired results.