| 摘要 |
<p>A suction excavator comprising an air pump for generating a flow of air, a nozzle (11) through which air is drawn under the influence of the air pump, the nozzle being arranged when in use to suck up spoil from an excavation (10) and means (18, 20, 23, 25, 30, 40...) for separating spoil (22) from the air drawn through the nozzle. The excavator is provided with a fuel gas detector (21, 51) to detect for the presence of fuel gas in the flow of air drawn up through the nozzle (11). When fuel gas is detected a valve (28) may be actuated to interrupt the flow of air up through the nozzle (11) and instead to admit air from a substantially fuel gas free source (27a) to flush any fuel gas out of the system reducing the risk of an explosion.</p> |
