| 摘要 |
<p>A sand casting method for a valve body with flanges at both ends has been modified in such a way that the flanged faces need not be machined afterwards and that no machining allowance need be made. This has been achieved by replacing the conventional core which has a dia. to suit the inflow and outflow bores, by one which is widened to the full dia. of the flanges. The flange face is thus bounded, not by the moulding sand, but by the core with its much better surface finish.</p> |
