Formulation Of Specification For Chromium-molybdenum Steel Petrochemical Pressure Vessel

The petrochemical industry is an important foundation of national economy.Pressure vessels are the core equipment of the petrochemical industry in which various chemical and physical reactions take place,usually under high temperature and high pressure conditions.As such,the safty in the design,production and usage of pressure vessels is highly guaranteed by the government and should be carried out very carefully abiding by GB/T 150;in some circumstances,TSG 21 are additionally required to be followed.Despite these,particular specifications are still needed for pressure vessels used in the petrochemical industry because of the harsh conditions(e.g.exposure to hydrogen)that the vessels will encounter.In this work,such a particular specificaiton in the manufacture of pressure vessels,working under high temperature,high pressure and and hydrogen enviorment,by using 14Cr1 MoR and 12Cr2Mo1 R are formulated.On basis of the manufacture experiences over the years,we put forward suitable parameters in the control of the chemical composition of raw materials,through the manufacture procedure(mainly welding)of the vessel,to quality verification of the product.For raw materials,the phosphorus content is reduced from ?0.020% to ?0.010% and the toughness increased against hydrogen embrittlement.For the manufacture procedure,the hardness,cold cracks and reheating cracks of welding joints are specifically considered.For quality verification of the final product,nondestructive tests for welding joints are intentionally specified.The final specification resulted from this work has already been applied in our company.