钢质燃气管道在线补板引流焊接技术研究

Research on In-service Welding Technology with Complementary Plate Flow Diversion for Steel Gas Pipeline

阐述在线补板引流焊接基本原理,分析在线焊接的烧穿问题。将管道视为单层圆筒壁,理论分析焊接熔池传热的热流密度。以材质为Q235B,规格分别为D89×4、D219×7、D426×7的钢管进行常压补板焊接试验,分析钢管允许带压施焊的压力。D89×4、D219×7、D426×7钢管的允许带压施焊的压力分别为0.52 MPa、1.20 MPa、1.06 MPa。因此在此3种规格的钢管上实施在线补板引流焊接,在合理控制燃气压力的条件下,不会发生烧穿问题。

The basic principle of in-service welding with complementary plate flow diversion is described, and the burn-through problem during in-service welding is analyzed. The density of heat flux for heat transfer in welding molten pool is theoretically analyzed by considering the pipeline as a single-layer cylindrical wall. The atmospheric pressure complementary plate welding tests of steel pipes with material Q235B and specifications of D89 ×4, D219 ×7 and D426 × 7 are performed, and the allowed pressure during hot-tapping welding of steel pipe is analyzed. The allowed pressures during hot-tapping welding of steel pipes with specifications of D89 × 4, D219 ×7 and D426 × 7 are 0.52 MPa, 1.20 MPa and 1.06 MPa respectively. Therefore, burn-through problem will not occur during in-service welding with complementary plate flow diversion on steel pipes with the three kinds of specifications under the condition of reasonable control of gas pressure.