Tunnel shot blasting machines for forged tools and shovels at Truper, Mexico

All three have a double lining in the impact zone —manganese steel plus high-chrome cast iron—, entry and exit vestibules with rubber curtains, abrasive recovery with bucket elevator and separator, and an automatic abrasive loader. The conveyor on the 2021 machines has a 44 m path and hooks rated for 200 kg each.
The shovel tunnel adds HMI control, a variable frequency drive on each blast wheel, vibration sensors with on-screen alerts, automatic adjustment of the abrasive curtain, and communication for remote assistance.
The forging line runs on carbon steel shot. Dust from all three machines is captured by cartridge dust collectors.

On the shovel line, output depends on how many parts fit on each hanger without shadowing each other. During the trials we designed a loading fixture that takes shovels of different sizes, together with a new setting of the wheels' blast pattern, to load more parts per meter of conveyor without compromising the finish.
With that setup, the trials showed a capacity of 17,000 to 51,000 shovels a day over two shifts, depending on shovel size.

Both 2021 machines were tested at our plant before shipment, with Truper engineers present and using their own parts. Components were checked against the quotation, along with the control systems and the blasting results, and the final adjustments before dispatch were put in writing.
The 2021 forging tunnel built on seven years of experience with the first one.

Truper ran the first tunnel from 2015 and, when it needed more capacity, came back to CYM for two more machines. Today there are three CYM tunnels at the same plant.