Method and plant for building tyres for vehicle wheels

A method for building tyres for vehicle wheels, comprising:

• moving a plurality of building drums along a closed first-stage path,
• moving a plurality of carcass sleeves being processed along an open first-stage path, wherein along a first stage operating section in common between said closed first-stage path and said open first-stage path each carcass sleeve being processed of said plurality of carcass sleeves being processed is built on a respective building drum of said plurality of building drums, said open first-stage path ending at a gripping ring arranged in a fixed reference position,
• moving a plurality of auxiliary drums along a closed second-stage path,
• moving a plurality of outer sleeves being processed along an open second-stage path, wherein along a second stage operating section in common between said closed second-stage path and said open second-stage path each outer sleeve being processed of said plurality of outer sleeves being processed is built and moved on a respective auxiliary drum of said plurality of auxiliary drums, said open second-stage path ending at said gripping ring,
• at the end of the second stage operating section, separating from the respective auxiliary drum a first outer sleeve being processed of said plurality of outer sleeves being processed and holding said first outer sleeve being processed by said gripping ring,
• at the end of the open first-stage path, arranging a first carcass sleeve being processed of said plurality of carcass sleeves being processed in a coaxial and radially inner position with respect to the first outer sleeve being processed held by said gripping ring, and
• shaping, inside the gripping ring, said first carcass sleeve being processed, assembling said first carcass sleeve being processed with said first outer sleeve being processed to obtain a first green tyre being processed.

A plant for building tyres for vehicle wheels, comprising:

• a first stage building line defining a closed first-stage path for moving a plurality of building drums and an open first-stage path for building and moving carcass sleeves being processed, wherein said closed first-stage path and said open first-stage path have a first stage operating section in common for building and moving each carcass sleeve being processed of said plurality of carcass sleeves being processed associated with a respective building drum of said plurality of building drums and wherein said first stage building line comprises a plurality of first stage work stations arranged along a portion of the first stage operating section,
• a second stage building line defining a closed second-stage path for moving a plurality of auxiliary drums and an open second-stage path for building and moving a plurality of outer sleeves being processed, wherein said closed second-stage path and said open second-stage path have a second stage operating section in common for building and moving each outer sleeve being processed of said plurality of outer sleeves being processed associated with a respective auxiliary drum of said plurality of auxiliary drums and wherein said second stage building line comprises a plurality of second stage work stations arranged along a portion of the second stage operating section, and
• a gripping ring arranged in a fixed reference position, wherein said open second-stage path and said open first-stage path end at said gripping ring configured for the assembly of said first carcass sleeve being processed with a first outer sleeve being processed.