直埋供热管道预热工艺分析OA

Taking the preheating construction of two preheating sections as an example,the preheating effect was evaluated and construction experiences were summarized.During the preheating period,the tem-peratures of the two preheating sections did not fluctu-ate significantly,the pipelines were heated evenly,and the pipeline deformation was fully released,resulting in an ideal preheating effect.During the preheating process,after the pipeline reaches the preheating temperature,it should not be backfilled immediately.A certain period of constant temperature should be maintained to fully release the pipeline deformation,and the backfilling can only be performed after verifying that the pipeline elongation has reached the calculated elongation.During the preheating pro-cess,both ends of the supply and return pipes are kept open for preheating,and additional temperature mea-surement points are arranged to effectively control the elongation of the supply and return pipes.The connect-ing bolts are required to be evenly distributed along the circumference of the pipe nozzle,so as to ensure uni-form heating and uniform deformation of the pipeline.