| 摘要 |
<p>The invention concerns an element for securing metal plates and composite panels with metal cover sheets in place from one side only, in particular composite panels with a plastic core and cover sheets made of aluminum or aluminum alloys; the element comprises a metal bolt with a shaft and a head, the head featuring a ring-shaped welding surface delimited inside and outside by a closed cone segment on which a ring-shaped arcing ring is provided, the bolt is joined to the metal cover sheet by condenser discharge welding, the composite panels may be employed as curtain walls or room dividers, where it is desirable to secure the panels at one side only.</p> |
