Apparatus for automatic joint machining in heavily thick cylinders

An apparatus for the automatic machining of joints in cylinders comprising a handling device, a first base structure attached to said handling device and provided with vertical guides, a first carriage slidable on the said vertical guides, a second base structure attached to said carriage and provided with horizontal guides, a second carriage slidable on said horizontal guides, a hydropneumatic device mounted on said second carriage and comprising at least one double acting pneumatic piston and cylinder assembly and a hydraulic damper, an operating head, and means attaching said operating head to said hydropneumatic device, said attaching means including means for angularly orienting said operating head relative to said second carriage about a vertical axis, said pneumatic piston and cylinder assembly having a lower chamber and an upper chamber, means for supplying said lower chamber with fluid at a first pressure to cause a fast lifting of said head, and means for supplying said upper chamber with fluid at a second pressure lower than said first pressure to annul the upward thrust while supplying said operating head with a downward operative thrust of a constant value.