卡箍装配缺陷对管道强度的影响分析

卡箍装配是管道装配中最常用的方法,装配缺陷严重影响管道的使用寿命和稳定性。利用ANSYS有限元软件对管道的卡箍装配进行模拟,分别建立正常、过紧和松动三种装配情况下的管道模型,求解并比较了各种装配状态下管道模型的应力、位移和固有频率等特征量。通过改变缺陷装配下管道模型的关键参数,探究装配缺陷程度对管道强度的影响。计算结果表明:装配缺陷使管道的强度特征量发生改变,并且管道的强度随缺陷程度的不同而不同。

Economy of Energy during Refrigerating Machine Operation

Idealized cycles of refrigerating machines with adiabatic and isothermal compression of refrigerant vapor were investigated. Energetic characteristics of cycles： specific mass and volume cooling capacity q0 and qv, work of compression 1, refrigerating coefficient of performance e and power N for drive of compressor were compared. These characteristics were calculated for eight refrigerants at temperature of their condensation 30 ℃ and temperatures of boiling -15℃ and -30 ℃. The calculations show that the use of isothermal compression of refrigerant vapor ensures economy of energy during refrigerating machine operation.