Study On Design And Manufacture About Pressure Strengthening Static Cryogenic Vessel

This article bases on the research of pressure strengthening austenitic stainless steel static cryogenic vessels. The pressure strengthening theory is to be studied, and technique is applied to design and manufacture of pressure product. Our company has successful design and manufacture experience of strengthening product according to ASME and EN standard, which could to be the base of developing strengthening product project. we have finished simulated pressure strengthening product experiments, the article will make discussion and study on research,design and manufacture of pressure strengthening austenitic stainless steel static cryogenic vessels,refer to that experiences.(1) The application, main structure, insulation type of pressure strengthening austenitic stainless steel static cryogenic vessels are to be discussed,and current application field of pressure strengthening technique in foreign countries is to be generalized, also the development of pressure strengthening cryogenic vessel in china will be discussed.The main study content of the article is to be introduced.(2) The austenitic stainless steel material mechanical property,allowable stress, ratio of yield strength and tensile strength are to be discussed after a series of experiments;The maximum strain control is to be discussed; The traits and suited conditions of pressure strengthening at room temperature and cryogenic temperature are to be discussed. The core strengthening technology,which is to be discussed on material selection,design, manufacture and welding;The special strengthening process technology of vertical cryogenic tank with multi-players insulation is to be discussed, and the method to finished it is to be put forward;Some problems and difficulties in project application are to be generalized according to engineering practice.(3) There are two types material S30408(06Cr19Ni10)and 1.4301(X5CrNi18-10)in the research, physical tests before cold strengthening and after cold strengthening on base material and welding metal have been completed, the thickness of test materials are 6mm,8mm and 10 mm, some researches are completed on test reports. The design issues of pressure strengthening cryogenic vessel are to be discussed, including material choosing, design stress value, main preferences of cryogenic vessel, calculation for the inner vessel subject to internal pressure and external pressure, method to deal with problems.The problem of outer jacket head subject to internal pressure is solved by finite element analysis method.(4) Insulation calculation between inner vessel and outer shell is to be researched. There are four types support structure to be contrasted. The problems of the strengthening cryogenic tanks are to be analysed,the finite element analysis method is used in safety performance calculation and estimate of a support structure subject to temperature load,suited for strengthening cryogenic tank.The support structure of horizontal cryogenic tank is to be discussed, stress calculated in dangerous working condition and improved.(5) The special requests during manufacture process of pressure strengthening cryogenic vessel will be analysed, and the problems, which include manhole setting, reinforcing ring, pipe line between inner vessel and outer shell, drainage structure, exhaustive structure,are to be discussed. The pressure strengthening strain measurement is to be explored, according to product examples. Research about welding influent factors of pressure strengthening vessel is to be completed, such as shell material, tensile strength upper limit, welding material, welding method and so on. The chemical components of fuse metal and base material are to be constructed through charts. The welding details are to be researched, which including butt welding, welding between nozzle and shell, weld details of butt welding of reinforcing ring, according to safety performance and strengthening deformation.