| 摘要 |
The supporting frame for a manhole cover is held in the required position, whilst the road surface is being finished, by means of a frame with three telescopic arms. The length of each arm (12, 13) is adjusted so that the angle section (22) at the end of each arm fits over the edge of the manhole. Each arm supports a screw jack (24) which has an attached angle bracket (25) which supports the manhole frame (R). The frame is brought to the required height by the jacks and then held in that position whilst the road surface around the manhole is built up to the required height. USE - Fitting of manhole covers.
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