Solution & Implementation
The hydraulic arm assembly being replaced, requiring Furmanite’s on-site machining skills, was on the car dumper at the Dampier port facility, where trains come in from Hamersley’s six mines in the Pilbara on the company-owned and maintained heavy haul railway. A new arm was procured and, in order to fit it, new mounting holes had to be drilled and reamed to secure the hydraulic arm to the car positioning carriage. A window of just 12 hours was allocated for the job to be completed within the shutdown period. Any delays would mean disruption to operation, and were clearly to be avoided.
To achieve this to the required level of accuracy and within the time frame three Furmanite crews operating three blind hole boring machines had to be used (with two technicians working with each). Testing was undertaken at the Furmanite workshop, drilling a hole into a test plate and reaming it to final size. Drilling 18 holes 45mm diameter would normally be a simple task, but when this work is required to be conducted on a car dumper positioning arm on-site in a very confined space, to tolerances of 0.05mm, through three plates totalling 120mm thick, and in a single 12 hour period, then the task is by no means simple. This is where Furmanite’s extensive on site experience and machinery came into play. Extensive jig fabrication and testing of the equipment undertaken prior to arrival was invaluable in ensuring minimum set-up time and confirming that the challenge could be met.