| 摘要 |
<p>A valve box (6) comprises a main valve (2) clamped between a pair of pipe flanges fastened with bolts (B,B1) and nuts (N,N1). The connection edge of the pipe flange (F) has an inlet port (7) and exit (8) for pressure fluid, which passes through a space extended upwards from the valve box. A cover flange neck (18) inserted between the bolts adjoining the periphery of pipe flange so that sidewall of the cover flange neck corresponding to each bolt is formed in narrow width.</p> |
