摘要 |
A screw pile stem includes a shank having an inwardly tapered portion at one end, and a helical screw on the shank, with the helical screw being of constant pitch and at least a part of the helical screw being on the tapered portion, and with a major diameter of the part of the helical screw on the tapered portion decreasing towards a small end of the tapered portion.
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