本一a和本二的区别

A low temperature stop valve, Unlike Example 1, Comprises a valve body 1 and a valve cover 2, A valve stem 3 is arrange in that valve body 1, One end of the valve stem 3 is provided with a valve disc 4, The other end of the valve stem 3 is provided with an adjusting handwheel 5, A low portion of that disc 4 is provided with a guide sleeve 6, The guide sleeve 6 is fixed by means of a connecting piece and a spring pad 8, Between that disc 4 and the guide sleeve 6 is provide a valve seat 7, Between that valve stem 3 and the valve cov 2 there is provided a packing assembly 9, The O-ring 10 is further arranged at the upper part of the packing assembly 9, the upper part of the O-ring 10 is provided with a packing gland 11, the valve body 1 is provided with an arc-shaped end face 12, the arc-shaped end face 12 forms a line seal between the valve body 1 and the valve seat 7, the contact end of the valve disc 4 and the valve seat 7 is provided with a water grain surface 41, the packing assembly 9 comprises a flexible graphite packing layer, and the valve body 1 is provided with a liquid inlet cavity and a liquid outlet cavity.这是一个战火频燃、纷争不断的动荡时代，一群有志之士集结在一起，计划盗走帝国大规模杀伤性武器“死星”的设计图。这个在《星球大战》系列里非常著名的重点事件，让一群平凡普通人结成了同盟，决定为世界的改变做出贡献；而在绝密行动的进行中，他们也逐渐成长为顶天立地的英雄。越来越多的内幕被挖了出来，大家的确有点同情天启，但是却没有人看好这部电视剧。The column of implementing mediators is as follows:Training Doctors with Ace Training Method//159　　但对于急于寻找失踪儿子的医生阿尔玛来说，这一切都可以归结为她成为被困在非战区内的居民的希望的象征。沉吟了一会。