| 摘要 |
<p>A surface box for covering over and guarding the operating rod of a gate or other valve in underground piping has a tube-like supporting frame and a rod guard sleeve mounted therein so that it may be moved upwards and downwards in translation for adjustment, for which purpose it is supported by a thrust screw on the supporting frame. To keep the sleeve from being tilted sideways and the operating rod of the valve damaged, the rod guard sleeve is keyed in the supporting frame and is guided by at least one guide ridge in the frame.</p> |
