NIB-SEAL on sweat ball valves are shipped unassembled.

在焊接球阀上，NIB-SEAL在装时处于未组装状态。

The condensability of liquid,the Westphal's effect and the continuous flow condition are not only comprehensively considered,but also the dynamic property of the ball valve being established.

结合现,根据直线电机采油泵动特性,综合考虑了液压缩性、魏氏效应、液连续流动条件和球阀动力特性,建立了直线电机采油泵球阀动规律精确动微分方程组。