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清心去火，凝神安眠的。Chapter 31岳灵珊对他有情有义，他要对岳灵珊有始有终。滚粗。大王……不可倾巢而出。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, An O-ring 10 is further dispose at that upper portion of the packing assembly 9, An upper part of that O-ring 10 is provide 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, the valve body 1 is provided with a liquid inlet cavity and a liquid outlet cavity, the two O-rings 10 are concentric arranged, and the inner diameter and outer diameter of the two O-rings are different.