高温工况下安全阀的整定压力偏差计算方法

Assessment Method of Set Pressure Deviation for Safety Valves under High Temperature Conditions

经验表明,安全阀离线校验时常温条件下确定的整定压力,与之后用于高温工况时的实际起跳压力相比存在一定的偏差。因此,提出了一种针对高温安全阀的整定压力偏差计算方法。首先通过CFD技术得到高温工况下的安全阀温度场;然后根据阀盖和弹簧上的温度分布计算出弹簧的实际压缩量与刚度;再结合阀内弹簧在常温下的初始压缩量与刚度,求出整定压力偏差。应用本文方法对A48Y-40安全阀进行整定压力偏差的计算和预测,并采用ABAQUS软件进行了复算验证。案例分析结果表明,用本文方法计算得出的结果具有较高的准确度,对安全阀的校验和使用具有一定的指导意义。

Practical experience suggests that the set pressure determined in bench testing maybe different from its actual opening pressure when the safety valve＇s operating temperature is high. Therefore ,this pa- per presents a method for evaluating the set pressure deviation of high temperature valves. First, CFD method is used to obtain the temperature field of the whole valve. Then, the actual compression and stiff- ness of the spring are calculated according to that temperature distribution. Finally, the set pressure devia- tion is calculated with these data. A case study is carried out with an A48Y -40 safety valve, results show that the assessment method proposed in this paper has high accuracy and provides reference meaning to safety valve inspection and application.