T91高压锅炉管的工艺研究

Research on Technical Process of T91 High Pressure Boiler Tube

为满足制造亚临界、超临界电站锅炉的需求，提高生产效率、降低成本，采用连铸坯工艺试制了T91高压锅炉管。本文介绍了试制T91钢管的工艺过程，并对试制过程中的内折缺陷进行了分析；通过多次试轧形成了在现有装备条件下批量生产该产品的可行工艺；对产品性能进行了测试。结果表明，试制生产的T91钢管化学成分、组织、力学性能等各项性能指标都能满足ASMESA-213规范要求；试制的T91钢成品样管在625℃下十万小时持久强度可达73．3MPa，满足ASMESA-213及GB5310标准的要求，可以用于锅炉制造；通过穿孔和轧制工艺控制，使T91钢处于最佳塑性温度范围1100℃～1250℃内．可明显减少内折缺陷。

To meet the requirement of sub-critical and super-critical power plant boilers fabrication, and to improve the producing efficiency and reduce the costs of production, T91 high pressure boiler tube was trial-produced. The present paper describes the technical process and analyses the interior fold defect during the process. After several times of trial rolling, the feasible process parameters for mass production were determined under existing equipment conditions. Properties of the prod- uct were examined. Results showed that the chemical compositions, structures, mechanical properties and other performance indexes of the trial-produce T91 steel tube met the requirement of standard ASME SA-213. The 100,000 hours creep rupture strength of the trial-produced T91 steel tube at 625℃ reaches 73. 3 MPa, which meet the standard ASME SA-213 and GB5310, consequently it can be used for boiler manufacturing. To control the process of rotary piercing and rolling, making T91 steel in the best plastic temperature range of 1100～1250℃, the interior fold defects can be significantly reduced.