BMT WBM has deployed its DuraCluster modification and repair scheme that improves the fatigue performance of cluster joints on existing tubular dragline boom designs.
Demonstrating ease of installation and operational suitability, BMT, together with a major operator in the open-cut coal sector, has replaced a number of fatigued boom clusters with DuraCluster.
After the DuraCluster has been installed, the modification for tubular boom draglines lowers maintenance and inspection workloads and also reduces the problem of long-term fatigue cracking associated with the existing cluster design.
The long booms of draglines comprise a number of tubular chords with interconnecting lacings welded to the chords at cluster joints. Stresses are concentrated at the cluster joint weldments and over time, fatigue cracking becomes endemic. BMT’s methodology prevents the need to cut and replace windows in lacings by removing the problematic design detail and improving load paths. Furthermore, DuraCluster can extend the fatigue life of dragline booms by reducing the stress concentrations.
Charles Constancon, Director of Canadian Services at BMT WBM explains: “A boom replacement can cost in the region of US$20 million and would require a three month machine outage. With BMT’s modification and repair, the cluster design can be upgraded in around one week per cluster, depending on the extent of chord repair required, while multiple clusters can be modified simultaneously. With equivalent repair costs reduced to approximately US$2 million, this is an extremely attractive incentive for mining companies. While DuraCluster provides a step change in life to cracking for tubular boom construction, it is equally applicable to tubular masts.”
Paul Charlton, Managing Director of BMT WBM’s machinery group comments: “The innovative design developed in our Vancouver office allows lacings to be cut away from the chord, providing easy access to remove damaged or previously-repaired material. The exposed chord can then be inspected and fully weld repaired before installing the plate. BMT’s innovative methodology delivers multiple benefits.”
Adapted from press release by Joseph Green
Read the article online at: https://www.worldcoal.com/mining/21052015/bmt-release-duracluster-2308/