The ethylene crackingtubes pack-carburized in a laboratory(P tube) and carburized during servicing in a cracking furnace (S tube) are studied.
对实验室固体渗碳（P管）和裂解炉运行渗碳（S管）的乙烯裂解管进行了研究。
2
The carburizing damage of HP type ethane crackingtubes after 40000hours of service is analysed using metallographic methods, and the tensile and creep rupture tests are conducted.
对运行了4万h的HP型乙烷裂解炉管的渗碳损伤进行了金相分析，并测定了炉管的力学性能。
3
It showed that a fast cooling after drawing was of benefit to dimensional stability, straightness, environmental stress cracking resistance, and strength of the drawn tubes.