Rotary table lightering method for ocean engineering crane

The invention discloses a rotary table lightering method for an ocean engineering crane, which comprises the following steps: before general assembly, erecting a general assembly jig frame, and marking arranging positions of various jig frames on the ground according to a general assembly jig frame arrangement diagram, wherein the numbers of the jig frames are 1 to 42; manufacturing the jig frames 1 to 42 in advance; carrying out machining after 42 jig frame rotary table overall structures are well welded on the jig frames in an assembling manner; during machining, dismantling part of the jig frames; after machining, assembling the arm supports, the front legs, the rear legs and the pre-assembled arm supports of a rotary table in advance; placing conveying cross beams and trestles; mounting electric appliances, equipment and fittings after the crossed cross beams and the trestles are well placed; and placing rails and a hydraulic trolley, lifting the whole rotary table, cutting off all the jig frames, and con