E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
E21D11/14—Lining predominantly with metal
E21D11/18—Arch members ; Network made of arch members ; Ring elements; Polygon elements; Polygon elements inside arches
E21D11/183—Supporting means for arch members, not provided for in E21D11/22
Boulon demontable pour assembler de facon tournante l'un a l'autre deux elements mecaniques de petites dimensions axiales, particulierement pour des systemes de leviers de machines textiles
Perfectionnements apportes au bridage des carters de machine constitues d'au moins deux parties dont l'une est un metal de relativement faible durete