| 摘要 |
1,190,659. Making valves. ROCKWELL MFG. CO. 6 Dec., 1967 [13 Dec., 1966], No. 55507/67. Heading B3A. [Also in Division F2] A rotary spherical plug valve is made by assembling elastic deformable seat rings either side of a plug with spherical seating surfaces within the inner ends of two fluid passage sections 12, 13 forming a valve cavity to give an initial pre-load to the seat rings, welding the two sections at 32 and cooling the weld by passing liquid through closable holes in the wall of the valve cavity to shrink the weld and give an additional pre-load to the seat rings. Flange 26 on the section 12 slides in cavity 27 of the section 13 to prevent welding material falling into the valve cavity and when the flange abuts the wall 144 during shrinking the two sections are prevented from moving closer together. Semi-circular cut-outs in the inner ends of the sections allow sleeves for valve bearing trunnions to be welded at 24 to the two sections. |
