A system for holding a tubular sleeve (2) in a receiving structure during setting of a cement or other binder introduced in a fluid state between the sleeve (2) and the receiving structure, comprising:—at least one expandable structure (4) mounted on the sleeve (2), deformable from an inactive configuration allowing insertion of the sleeve (2) in the receiving structure to an active configuration immobilizing the sleeve (2) in the receiving structure,—at least one corresponding tool to be inserted in the sleeve (2), configured for acting on the expandable structure (4) to cause it to pass from the inactive configuration to the active configuration.