Apparatus and method for performing external surface work on ship hulls

Apparatus for performing surface work such as cleaning and painting on an external generally vertical surface of a ship hull, comprising:.

• a plurality of towers arranged side by side in a set to be supported on a generally horizontal support surface in confronting relation to a longitudinally and vertically extensive portion of a generally vertical external surface of a ship hull, each tower comprising a ..plurality of modules destackably stacked one upon another and including at least a base module arranged to be directly supported on said support surface, and an upper module arranged to provide an upper end for the respective tower;
• shroud means mounted to said towers for cooperating with said ship hull surface for enclosing a confined space within and forwardly of said set of towers;
• a ventilation system including ducting for suppplying fresh air through said shroud means to said confined space, and ducting for recovering air laden with dust, paint overspray and/or volatile organic chemicals through said shroud means from said confined space, said ventilation system including ventilating machinery mounted on said upper modules;
• said shroud means comprising end curtains for sealing between end towers of said set and said ship hull surface, face panels for closing off respective faces of said tower modules, corner seals for sealing between adjoining edges of adjoining ones of said tower modules both on same ones of said towers and on adjoining ones of said towers, between an upper horizontal edge of each said upper module and said ship hull surface, and with said hull surface at a lower, forward extent of said shroud means.

Apparatus for performing surface work such as cleaning and painting on an external generally vertical surface of a ship hull, comprising:

• a plurality of towers arranged side by side in a set to be supported on a generally horizontal support surface in confronting relation to a longitudinally and vertically extensive portion of a generally vertical external surface of a ship hull, each tower comprising a plurality of modules destackably stacked one upon another and including at least a base module arranged to be directly supported on said support surface, and an upper module arranged to provide an Upper end for the respective tower;
• shroud means mounted to said towers for cooperating with said ship hull surface for enclosing a confined space within and forwardly of said set of towers;
• a ventilation system including ducting for supplying fresh air through said shroud means to said confined space, and ducting for recovering air laden with dust, paint overspray and/or volatile organic chemicals through said shroud means from said confined space, said ventilation system including ventilating machinery mounted on said upper modules;
• at least one of said towers supporting a vertical elevating trolley for vertical movement and stationing at desired heights within said confined space;
• and
• further including:
• a track base plate extending horizontally longitudinally of said set of towers;
• a pair of longitudinally spaced cantilever arms mounted at rear ends of said trolley and at forward ends to said track base plate and arranged to extend and retract said track base plate forwardly away from and rearwardly towards said trolley;
• said track base plate mounting horizontally, longitudinally extending track means for mounting work equipment for longitudinally traversingly applying work to said ship hull surface.

A method for performing work on a generally vertical external surface extending perimetrically about the perimeter of a hull of a ship supported on a generally horizontal surface forming a deck of a floating drydock disposed in a body of water, for cleaning and painting said surface of said ship hull in a succession of phases, comprising:

• erecting on said deck surface adjacent and extending longitudinally along a first portion of said surface of said ship hull a first set of enclosed staging devices;
• said first set of staging devices including a plurality of modular towers disposed side-by-side, and a shroud which is open towards said first portion of said surface of said ship hull and effectively encloses a confined space collectively around sides, back and top of said first set of staging devices, and against said deck surface and said surface of said ship hull perimetrically of said first portion of said surface of said ship hull;
• each said modular tower including a lower module directly supported on said deck surface and a full machinery upper module directly supported on a respective said lower module;
• each full-machinery upper module supporting for vertical movement and stationing at selected levels, a respective vertical elevating trolley;
• a working equipment support platform for each said trolley;
• for each said trolley, horizontally forwardly extensible and rearwardly retractable cantilevering arm means having near ends thereof mounted to the respective said trolley and forward ends thereof mounting the respective said working equipment support platform;
• air-handling ventilation lines and equipment service lines penetrating said shroud, being supported by each respective said full-machinery upper module and effectively extending to and from each said working equipment support platform;
• on each of a plurality of said working equipment support platforms, connecting abrasive blasting heads to said equipment service lines and to said air-handling ventilation lines and, while traversing said abrasive blasting heads relative to said surface of said hull and varying levels of the respective said trolleys, applying abrasive grit from said heads against said surface of said hull and thereby blasting chips of paint and/or scale and dust from said surface of said hull, and carrying at least some of said chips and dust, out of said confined space through said air-handling ventilation lines;
• thereafter, on each of a plurality of said working equipment support platforms, connecting paint-applying spray heads to said equipment service lines and to said air-handling ventilation lines and, while traversing said paint-applying spray heads relative to said surface of said hull and varying levels of the respective said trolleys, applying paint from said paint-applying spray heads onto said surface of said hull and thereby painting said surface of said surface of said hull and carrying at least some paint overspray and volatile organic chemicals from said paint, out of said confined space through said air-handling ventilation lines;
• erecting on said deck surface adjacent and extending longitudinally along a second portion of said surface of said ship hull lower modules for a second set of enclosed staging devices;
• lifting said full-machinery upper modules from respective ones of said lower modules of said first set of enclosed staging devices and transferring and lowering those full-machinery upper modules onto respective ones of said lower modules of said second set, and thereby providing a second set of enclosed staging devices likewise including a second plurality of modular towers and having a second confined space collectively around sides, back and top of said second set of staging devices;
• said trolleys being thereby supported for vertical movement and stationing at selected levels in said second confined space;
• lifting ventilation-only upper modules and lowering them onto respective ones of said lower modules of said first set, each said ventilation-only upper module including respective portions for a shroud for being open towards said first portion of said ship hull surface and for confining respective portions of and reconstituting said confined space around sides, back and top of said first set of staging devices, as modified by replacement of said full-machinery upper modules by said ventilation-only upper modules;
• air-handling ventilation lines penetrating said shroud portions and being supported by respective ones of said ventilation-only upper modules;
• during a period of time while volatile organic chemicals are continuing to evaporate from paint applied to said surface of said hull, carrying at least some of said organic chemicals out of said reconstituted confined space;
• and
• thereafter, dismantling said ventilation-only upper modules from said lower modules of said first set, for reuse in successive phases of work on said surface of said hull.