Delivery pipe system for liquid concrete has expanding and contracting seals and has telescopic mast sections making up telescopic delivery pipe with seals between adjacent sections

摘要

Liquid concrete is pumped to a delivery point through a telescopic pipe which is supported and directed by a telescopic mast. The sections making up the telescopic delivery pipe have seals between adjacent sections. The seals may be expanded and contracted at intervals as required to minimize friction and enhance the seal action.