| 摘要 |
<p>Continuous cement type pipe is produced on site in an open trench. A sliding carriage (with feed inlet) moves it along the trench, a casting device moulds concrete into the lower half of the pipe on the trench floor, and has a rigid cylinder which is convex on top. The carriage is drawn along the trench to move the casting device and cylinder and to mould the top half of the pipe, the material is poured into the inlet forming top and bottom halves of the pipe which remains stationary. The freshly formed top half (produced by the clydiner) is thereby left unsupported, while the top half is moved off the cylinder a form which is open underneath is left behind; this form is cured when the cylinder is removed from the top half and material for the top half is supported by that form until is cures. The form remains permanently in the pipe. Process saves cost and labour of stripping a mould; there is no restriction in dia. and formation of mould marks as weak areas is eliminated. Used for corrosion resistant applications.</p> |
