Steel plate for low temperature pressure container and producing method thereof

Abstract

The present invention relates to a steel plate used for a low temperature pressure vessel and the production method thereof. The steel plate has the main chemical composition content (wt percent) that C is 0.12-0.19 percent, Si is 0.15-0.45 percent, Mn is 1.2-1.6 percent, Nb is 0.015-0.050 percent, Ti is 0.01-0.03 percent, Ni is 0.10-0.35 percent, Al is 0.015-0.050 percent, and P is 0-0.015 percent; S is 0-0.01 percent, and the residual is Fe and inevitable impurity. The present invention uses a new process technology of hot billet steel furnace loading, intermediate billet water cooling, controlled rolling, controlled cooling accelerating, and normalizing, which is easy to be operated, reduces the dosage of the alloying element to the lowest, in particular, largely reduces the use of the precious metal Ni, the transverse impact power of the low temperature toughness 40 below zero is up to 164 J, transverse impact power of 30 below zero is up to 298 J, and CTOD is Delta 0.20 equal to 0.40 mm in the test condition that the temperature is 40 below zero. The cost of the steel type is relatively lower, the hourly output is high, the intensity is moderate, the plasticity is good, the low temperature toughness is high, the welding performance is extremely fine, and thereby the steel type can be widely applied to low temperature vessels for storing and delivering low temperature liquid in various industries and the petroleum and the chemical industry fields.

Description

technical field [0001] The invention belongs to the field of metal materials, and relates to a steel plate for low-temperature pressure vessels and a production method thereof. Background technique [0002] According to the relevant literature and the latest published patent technology, Chongqing Steel adopts V and Ti microalloying treatment technology. At present, only Shenyang Heavy Machinery Factory has applied for the Chinese patent of "a low temperature resistant weldable fine grain thickness direction steel plate". Application, its application number is 94110049, and the application date is August 2, 1995. The product formula ingredients in this technology include C, Mn, Si, P, S, V, Ti, Cu, Cr, Mo, Ni, Fe. On the one hand, the existence of Cu element increases the probability of cracks during continuous casting and heating rolling, which increases the difficulty of operation. On the other hand, Mo, Cr, and V elements increase the cost and increase the carbon equivalen...

AI Technical Summary

Problems solved by technology

On the one hand, the existence of Cu element increases the probability of cracks during continuous casting and heating rolling, which increases the difficulty of operation. On the other hand, Mo, Cr, and V elements increase the cost and increase the carbon equivalent at the same time. bad performance