摘要 |
<p>Device for fixing a flexible plastic film over metal frames to form e.g. a greenhouse comprises a close-fitting plastic sheath which transversely covers the film at the level of >=1 frame. Two tensioning cables slide within the sheath and are disposed one on each side of the frame. The sheath pref. has a width of 2-8 times the larger dimension of the section of the frame, is opaque coloured or metallised, and is made of polyethylene or vinyl resin. The cables are pref. plastic-sheathed metal cables, with chains at their ends to facilitate securing and tensioning.</p> |