| 摘要 |
<p>Hose for use in a device for extracting an undisturbed sample of earth from below ground level, is prepd. by drawing the hose through a bath of fluid whilst air is blown against the inner surface of the hose. A circular knitted hose is used, which, whilst it is being drawn through the bath is under longitudinal tension. Until the coating is stabilised, the longitudinal tension and the desired dia. of the hose are maintained. The fluid may be a monomer which polymerises at a temp. higher than that of the bath, and stabilising of the cladding on the hose is effected by polymerisation; the temp. being raised to a point above that of the bath, sufficient to initiate the reaction when catalysts are added. The vaporising of the solvent or the course of the polymerisation is pref. effected by hot air blown into the hose, the pressure of the air being sufficient to maintain the dia. required at least in the unstabilised zone. The hose is both flexible and elastic in the transverse direction and is esp. suitable for taking samples. IT stretches sufficiently for folding in the chamber of the sample taking device, without applying load to the sampel.</p> |
