The invention relates to a semi-sliding box-type
buttress of a floating production storage and offloading (FPSO) upper module. The semi-sliding box-type
buttress of the FPSO upper module mainly consists of a supporting circular stand column, side wing support plates, concave arc
wrist plates, rectangular
wrist plates, a box body, a sliding trapezoidal groove base plate, baffle plates, a sliding trapezoidal tooth base plate, a fixed end
metal gasket and a fixed end stand
pipe base plate, wherein the supporting circular stand column is a supporting body connected with an upper plate and a lowerplate of the box body; an internal supporting body of the box body is formed by
welding the side wing support plates, the concave arc
wrist plates and the rectangular wrist plates; the
metal gasket iswelded on a fixed end box body cover plate for reinforcing and balancing, so that a fixed end
buttress is formed; the baffle plates are welded on a sliding end box body cover plate along the bow andstern direction for limiting the cross sliding and vertical fluctuating of the sliding trapezoidal groove base plate; furthermore, the base plate is welded on the box body cover plates, and the sliding trapezoidal tooth base plate is in
lap joint with the upper part of the base plate, so that a sliding end buttress is formed; support legs for a frame platform are fixedly welded with a module buttress part in a form of simply supported beams, and are in partial
sliding contact. The semi-sliding box-type buttress of the FPSO upper module is reasonable in stress, high in adaptability of sea conditions and wide in applicable sea areas.