PURPOSE: To facilitate the changing of the direction of a heavy article, by removably attaching a required number of caterpillar roller units to the heavy article and attaching an air pallet to the article to change its direction through the action of the air pallet.

CONSTITUTION: Caterpillar roller units 10 are removably attached to the jack fitting members 25 of a heavy article 4 through pedestals 24 provided on the tops of the roller units. An air pallet 15 is removably attached to mounting flanges 26 provided on the heavy article 4. For conveyance, steel plates 42 are laid on a conveying path 41, the heavy article 4 is put on the steel plates and the article is then moved to a direction-changing point through the action of the caterpillar roller units 10. At the direction-changing point, compressed air is supplied to the air pallet 15 from a compressor 43 to expand air bags 17 and cause the air to go out of the internal chambers 21 of the bags through holes 20 and flow out in a direction B through the apertures between the steel plates 42 and the bags to floatingly support the heavy article 4. As a result, the direction of the heavy article 4 is lightly changed.