EST-TUN 13x23 shot blast tunnel and blast room for Pla, John Deere

Before painting, the frames, booms and welded structures of a sprayer must be clean and have the anchor profile the coating needs. They are long, heavy parts with complex shapes that travel through the plant hanging from the conveyor.

Three more conditions applied:

• Line pace. Blasting had to keep up with the power and free conveyor feeding the paint line, without unhooking the parts.
• Oversized parts. Some structures exceed the section of a tunnel, and others need manual touch-ups.
• Safety. John Deere requires explosion protection on dust collection at all its plants worldwide.

1. EST-TUN 13x23 tunnel with twelve 10 HP blast wheels. Parts pass through the cabinet hanging from the conveyor, on hangers up to 9 m (30 ft) long and 2 t (4,400 lb), at 0.3 to 1 m/min (1 to 3.3 ft/min). The 12 blast wheels, angled 35° to the travel direction, throw a total of 1,200 kg (2,650 lb) of shot per minute from different angles, reaching every face of the structure with no blind spots. At the exit, in the blow-off area, the operator removes the shot left on the parts.

2. Blast room, 5 × 3.62 × 12 m (16 × 12 × 39 ft). It takes parts up to 2.4 × 1.6 × 9.5 m and nearly 2 t, brought in hanging. The operator works with a blast pot that refills automatically from the silo, so there is no need to leave the room to load abrasive, and the remote control switches between blasting and blow-off on the same hose. Abrasive recovery is 100% automatic: oscillating scrapers cover the whole floor and carry the abrasive to the elevator and the separator. The room has sound-absorbing panels, 1,500 lux LED lighting mounted outside and positive-pressure protective equipment for the operator.

3. Two dust collectors with explosion protection. Each machine has its own Camfil Farr Gold Series collector, with explosion vents, an isolation valve on the inlet duct, fire sprinklers in the clean-air plenum, an abrasion-resistant inlet, a rotary valve for abrasive dust and pulse-jet cartridge cleaning. More on cartridge dust collectors.

Both machines have been working at the Las Rosas plant since 2024. Structures leave the tunnel or the room and stay on the hook all the way to the paint line.