The Oyu Tolgoi Copper Mine (OT Mine) is one of the largest copper mines in the world and an important economic pillar of Mongolia. Rio Tinto and the Mongolian government hold 66% and 34% of the shares respectively. The copper and gold produced by the copper mine account for 30% to 40% of Mongolia’s GDP. The OT mine is about 80 kilometers away from the border between China and Mongolia. Since July 2013, it has gradually exported copper fine powder to China. The main thing around this project is the super giant on this land: electric shovel.
Project Background
The electric shovel is one of the main mining equipments in the 10 million-ton open-pit mine. It has high productivity, high operating rate and low operating cost. It is a recognized model in the mining industry. The electric shovel consists of a running device, a rotating device, a working device, a lubrication system, and a gas supply system. The bucket is the main component of the electric shovel. It directly bears the force of the excavated ore and is therefore worn. The stick is also one of the main components in the excavation process. Its function is to connect and support the bucket, and to transmit the pushing action to the bucket. The bucket performs the action of excavating the soil under the combined action of pushing and lifting force; the most core crawler device in the traveling mechanism eventually makes it move directly on the ground through related transmission mechanism.
However, in day-to-day work, the oversized electric shovel weighing 2,700 tons needs to be overhauled regularly to ensure continuity of planning.
Difficulty
For such a large and rigid object, when replacing components such as crawler walking devices and rotating devices, it is necessary to raise the whole machine synchronously, and the smooth top can reach a certain height to facilitate on-site maintenance. How to ensure that the structure of the whole machine is not damaged, and that it can be balanced too?
Solution
Canete technical team has repeatedly communicated with the OT mine maintenance department, and systematically analyzed the force. Finally, it is confirmed that the patented product developed by Canete-PLC multi-point synchronous jacking hydraulic system is used for 10-point servo controlling.
The purpose is to distribute the large electric shovel locally to 10 stress points, 6 of which are supported by 600 ton stroke 180mm double-acting large-tonnage hydraulic jacks, and the other 4 points adopt 200 ton stroke of 1800mm hydraulic jacks. Through the double closed-loop control of the displacement and pressure of 10 jacks, the problem of displacement synchronization and stress equalization in the field is solved.
Project Completion
The project has completed the maintenance work on May 5, 2019. According to the specific implementation of the site, the displacement accuracy is controlled to 0.2mm in the case of solving the stress balance, and finally meets the technical requirements.
Post time: May-15-2019