LNG接收站低温管道保冷安全及效果评价

LNG接收站保冷效果的好坏,直接关系到生产的安全平稳运行。为了对低温管道保冷现状进行评价,从2个方面进行了研究:1)采用表面温度与热流计法,对管道冷损失量进行测量计算;2)以大跨距直管为例,采用有限元分析方法,对其进行强度校核与极限载荷分析。通过现场测量与计算,发现135个检测点中,冷损失量超出允许范围的比率高达71.9%,而且所有管道表面温度均低于露点温度。此种状况意味着应采取措施降低冷量损失。此外,经过数值模拟计算,认为管道载荷在容许范围内,并经现场验证,未发现明显的管道变形情况。

COLD INSULATION SAFETY AND EFFECT EVALUATION FOR CRYOGENIC PIPELINES IN LNG TERMINAL

The cold insulation effect of LNG terminal is directly related to safe and stable production.In order to evaluate the present cold insulation situation of cryogenic pipelines,a study was carried out from two aspects.Firstly,the cold loss of pipeline was measured and calculated by using surface temperature and heat flow meter method;Secondly,taking long-span straight pipe as an example,its strength and limit load were analyzed by using finite element analysis method.Through on-site measurement and calculation,it was found that out of the 135 detection points the ratio of cold loss exceeding allowable range was as high as 71.9%,and the surface temperature of all pipelines was lower than the dew point temperature.This means that some measures should be taken to reduce the cold loss.In addition,through numerical simulation calculation,it was considered that the pipeline load was within the allowable range,and no obvious pipeline deformation was found in field verification.