| 摘要 |
A hydraulically operated mine prop made of light metal, comprises an outer prop portion and at least one telescopic inner portion with at least one of these portions being provided with a non-sparking and impact-resistant metal covering. The covering may, for example, comprise steel, and an insulating layer is advantageously provided between the covering and the prop portion with which it is associated. The thickness of the covering is advantageously made from 0.2 mm to 0.6 mm. |
