Apparatus for automatically polishing butt weld of ultralong large-diameter pipeline

An apparatus for automatically polishing a butt weld of an ultralong large-diameter pipeline, comprising:

• a machine frame, comprising a base for being supported on the ground, a fixed frame mounted at the top of the base, and adjustable supporting feet mounted at a top end of the fixed frame and configured to be clamped on a surface of the pipeline;
• a polishing mechanism, comprising a rotating arm, a supporting column rotatably mounted on the rotating arm, and a polishing roll rotatably mounted on the supporting column in a circumferential direction of the polishing roll;
• an angle limiting assembly, movably mounted on the rotating arm, the angle limiting assembly being configured to limit an angle at which an outer side end of the supporting column swings upward;
• a roll driving part, mounted on the rotating arm, the roll driving part being in transmission connection with the polishing roll and configured to drive the polishing roll to rotate on the supporting column in the circumferential direction of the polishing roll;
• and
• an arm driving part, mounted on the fixed frame, the rotating arm being mounted on the arm driving part, and the arm driving part being configured to drive the rotating arm to rotate in a circumferential direction of the pipeline;
• wherein the rotating arm comprises an outer sleeve, an inner column body inserted from a bottom end of the outer sleeve and rotatably mounted in the outer sleeve, an inner driving cavity arranged inside the inner column body, an inner rod rotatably mounted in the inner driving cavity, an adjusting spring fixedly mounted at an inner side end of the inner rod, and a pulling block fixedly mounted at an inner side end of the adjusting spring, an outer side end of the inner rod extending to an exterior of the outer sleeve and being bent to be parallel to an axial direction of the pipeline, an inner wall of an outer side end of an inner cavity of the outer sleeve protruding inward to form a limiting ring matched with the diameter of the inner rod, a clamping groove being formed in an inner wall surface of the limiting ring, and a clamping block in sliding fit with the clamping groove being fixedly arranged on a surface of the inner rod;
• wherein a hemispheric sliding block is fixedly mounted on a surface of the pulling block, an inner wall of the inner driving cavity is provided with a horizontal rail and a spiral rail which are matched with the shape of the sliding block, the horizontal rail is arranged along a half circumference of the inner driving cavity, and one end of the horizontal rail is connected to a bottom end of the spiral rail;
• wherein a groove is formed in an inner side end of the polishing roll, a toothed ring is fixedly mounted on an inner wall surface of an end portion of the groove, a supporting plate is fixedly mounted at an inner side end of the supporting column, a wheel carrier is fixedly mounted on an inner side surface of the supporting plate, a ratchet wheel is fixedly mounted on the wheel carrier, a first ear plate parallel to an axial direction of the inner rod is mounted on an end surface of the outer side end of the inner rod, second ear plates are mounted on an outer circumferential surface of the outer side end of the inner rod, and the wheel carrier is rotatably mounted on the first ear plate;
• wherein the angle limiting assembly comprises a fixed rod fixedly mounted between the second ear plates, displacement springs symmetrically sleeved at two ends of the fixed rod, and a pawl rotatably mounted on the fixed rod, the pawl being mounted between the two displacement springs;
• wherein the roll driving part comprises a first motor fixedly mounted on the inner rod, a first gear connected to the first motor, a second gear and a first bevel gear which are rotatably mounted on the inner rod, a second bevel gear and a third bevel gear which are rotatably mounted on the inner rod, a fourth bevel gear rotatably mounted on outer side surfaces of the second ear plates with the axis of the ratchet wheel as the center of a circle, and a fifth bevel gear and a third gear which are mounted on the supporting plate, the first gear being meshed with the second gear, the second gear and the first bevel gear, the second bevel gear and the third bevel gear, and the fifth bevel gear and the third gear being connected through synchronous shafts, the first bevel gear being meshed with the second bevel gear, the fourth bevel gear being meshed with the third bevel gear and the fifth bevel gear, and the third gear being meshed with the toothed ring;
• wherein the arm driving part comprises a second motor fixedly mounted on the fixed frame, a rod connected the second motor, and a sliding base slidingly sleeved on the rod, the rod being arranged in the axial direction of the pipeline, a driving ring being fixedly mounted on a surface of the sliding base close to the second motor, a mounting groove being formed in an end portion of the sliding base away from the driving ring, and a bottom end of the inner column body passing through the top of the sliding base to be rotatably mounted in the mounting groove;
• wherein a displacement driving part for driving the sliding base to move in an axial direction of the rod is mounted on the fixed frame;
• and the displacement driving part comprises a third motor fixedly mounted on the fixed frame, a lead screw fixedly mounted on a rotating shaft of the third motor, and a threaded sleeve threadedly sleeved on the lead screw, an inner side end of the lead screw and one end of the rod away from the fixed frame being jointly connected with a fixed plate, and a top end of the threaded sleeve being connected to the driving ring;
• wherein a steering driving rack and a lifting driving rack are fixedly mounted on a surface of the fixed plate close to the rod;
• a steering driving gear capable of being meshed with the steering driving rack is fixedly mounted at a bottom end of the outer sleeve;
• a bottom end of the steering driving gear is mounted at the top of the sliding base through an unidirectional rotation assembly;
• a lifting driving gear capable of being meshed with the lifting driving rack is fixedly mounted at the bottom end of the inner column body, and the lifting driving gear is rotatably mounted on an inner bottom wall of the mounting groove;
• a lifting rail is arranged at the bottom of the lifting driving gear;
• and a first limiting bead in sliding fit with the limiting rail is fixedly mounted on the inner bottom wall of the mounting groove.