Productivity pains of a cement plant
Cemento Cruz Azul, a cement production company in Mexico, grappled with operational issues and downtime at its Hidalgo plant due to the cement ball mill’s main gear box.
Operating with a cement ball mill supplied by an original equipment manufacturer (OEM), the Hidalgo plant was subject to tooth breakages, abnormal operating behaviours, and ultimately, a loss in productivity. FLSmidth then stepped up to resolve the problem by providing Cemento Cruz Azul with the perfect solution - the MAAG® GEAR LGDX Gear Unit.
Selecting a sufficient solution
The Cemento Cruz Azul Hidalgo plant’s original gearbox was built in 1995. For nearly a quarter of a century in production with the original gearbox, the plant continuously experienced unexpected and costly shutdowns due to original equipment inefficiencies. The original gear unit was worn and could no longer perform. Due to the constant unreliability, Cemento Cruz Azul turned to FLSmidth to supply an innovative, trustworthy replacement.
We proposed the MAAG® GEAR LGDX Gear Unit as the design best able to meet the needs of Cemento Cruz Azul’s Hidalgo plant. Thanks to the flexibility of the MAAG® GEAR LGDX Gear Unit, the existing unit could be replaced without adapting the mill or its foundation,”
A customised, quality solution
The MAAG® GEAR LGDX Gear Unit can be installed as a retrofit on existing ball mills or as a new installation. “Keeping cost in mind, we reused the existing main motor, couplings and auxiliary drive to operate the new lateral drive,” Martin Baechler said.
The installed gear unit comes with an innovative new casing and a smart lubrication system. Uniquely, the casing is 100 percent symmetrical. This means, in case the toothing becomes worn out, the entire gearbox can be turned upside down to continue operating on the backside of the worn toothing.
As for the smart lubrication system, “it now separates the low-speed gearing from the rest of the gearbox to provide clean and fresh oil to more sensitive parts, like the bearings and high-speed gearing."
These innovative features deliver a longer service life for the bearings and gears, and in turn, enhances productivity.
In October 2018, the plant’s old gearbox was removed and replaced by the MAAG® GEAR LGDX-30 Gear Unit. The unit exchange took 13 working days, after which the mill was back in full operation.
In June 2019, the Cemento Cruz Azul Hidalgo plant was inspected by a LGDX Gear Unit specialists. After more than 3000 hours of operation, the LGDX Gear Unit‘s internal parts were found to still be in perfect working order. Today, the unit runs at a very low vibration level of only 0.7 mm/s rms and supplies reliable operation in a 24/7 production environment.
Lateral drives for horizontal mills
Globally, countless lateral drives are in operation throughout the mining and cement production industries.
In comparison to central drives, lateral drives for horizontal mills offer a host of advantages, particularly in terms of their space saving design. With the MAAG® GEAR LGDX Gear Unit’s design, the front and rear end of the mill are free for material inlets and outlets. The LGDX, like most common lateral drive designs, uses two output pinions meshing the girth gear, which is attached to the mill shell. The drive torque from the electrical motor is mechanically divided and balanced between the two pinions by the floating shaft.
- Sustainability: Offers the longest possible lifetime, achieved by updating the casing design and developing a smart lubrication concept.
- Productivity: Thanks to reliable operations and the high efficiencies of the LGDX, the productivity of any ball mill will reach new levels.
- Flexibility: The compact and symmetrical casing offers flexibility to replace nearly all old, worn lateral drives.