Large Equipment Paint Booths: Planning for Oversize Parts

Getting Oversize Parts In and Out

Material handling drives the layout. Parts may enter on rail carts that roll along tracks set into the floor, on transfer carts, on trailers, or hung from an overhead crane. Each method affects the booth differently. Rail and transfer carts need flush tracks across the threshold and floor designs that can carry the load. Overhead cranes need a slot or opening in the booth roof, with seals around the crane path, and the cabin must allow full hook travel. Plan the path from fabrication to the booth to curing and shipping so parts move forward without being lifted more often than necessary.

• Rail carts with flush tracks through the doorway
• Transfer carts or trailers for drive-in delivery
• Overhead crane access through a sealed roof opening
• A clear path from fabrication through finishing

Door Sizes and Sealing

Doors on large equipment booths are among the biggest components. They must clear the largest loaded part and its carrier with margin, which often calls for bi-fold, roll-up or sliding doors rather than swinging ones. Large doors are harder to seal, and leaks around them upset booth pressure and let dirt in. Consider how often doors will open, how long they stay open during loading, and whether personnel doors are needed so painters do not open the main doors. Door operators, controls and safety devices must be suitable for the booth environment.

Moving Air Across a Very Large Cabin

In a large booth, getting even airflow to every part of the cabin is a real design challenge. Crossdraft designs must push air across long distances without dead zones. Downdraft and side downdraft designs need plenums and exhaust spread across a wide area. Some large booths are divided into zones that can run independently, so painting one end of a part does not require ventilating the whole space at full volume. Air volume drives make-up air, heating and electrical loads, so energy planning is a major part of large-booth design.

• Even distribution without dead zones at the edges
• Zoned airflow to ventilate only the area in use
• Make-up air and heating sized for large volumes
• Electrical service for large fans and heaters

Lighting at Height

Lighting a tall cabin is harder than lighting a car booth. Ceiling fixtures far above the floor lose intensity before reaching lower surfaces, and tall parts block light to their own sides. Large booths usually combine ceiling lights with multiple rows of wall fixtures at different heights, sometimes angled to reach under overhangs. Fixtures must be reachable for relamping and cleaning, which can mean catwalks, lifts or service from outside the cabin. As with any booth, fixtures must be suitable for the spray environment.

Lifts and Platforms for Painters

Painters need safe access to every surface of a large part while holding proper gun distance. That usually means mobile lifts, man lifts or fixed platforms inside the booth, sometimes on both sides of the part. Lifts must be suitable for use in a spray area, and grounding of lifts and parts helps control static. Plan where lifts park, how they move without striking walls or lights, and whether their routes conflict with rail tracks or crane paths. Fall protection and lift training are part of the safety plan for any booth where painters work at height. Where parts are painted on several sides in sequence, think about whether the part can be rotated or repositioned inside the booth, which can reduce how much work happens at height.