Mainly pearlite steel and austenitic steels with different coefficients of linear expansion and poor thermal conductivity of austenitic steels produced.
Welded austenitic steel with pearlite steel should be used austenitic chrome-nickel content than high-alloy steel base metal welding materials, and even use linear expansion coefficients ranged between pearlite steel and nickel alloy austenitic steel Aluminium Welding Electrodes consumables to reduce residual stress. Welding materials shall meet the technical requirements of drawings in accordance with the provisions by welding procedure qualification JB4708. Because welding, flux national standard performance tests without bending, welding, mechanical properties test plate heat flux specification and product specification are not identical post weld heat treatment, with a lot of steel, a far cry from requiring welding "by welding procedure qualification by JB4708 "to ensure that the pressure vessel by welding standards through performance testing, but does not require welding furnace batch by welding procedure qualification.