High efficiencyPublished 16/4 at 16:21
In late 2017, Finnish demolition contractor T. Mäkelä Oy was awarded a demolition contract to tear down a four floor concrete block building in central Finland. This comprised of 3,000t of 12mm steel rebar reinforced concrete, which initially required tearing down using concrete pulverisers.
The second stage of the process was to crush the resulting large concrete blocks to a fragmentation size of 0-80mm, which would be reused in road foundation construction. This was accomplished using a Viper bucket attachment. “Instead of traditional crushers we used a Viper slow moving drum crushing bucket to crush the concrete. We have experience of jaw crushers but we selected the Viper VPCH 21 crushing bucket because a number of reasons with its superb capacity and no daily maintenance helping us to keep the tight schedule,” commented Mr. Kantola, the operator of the crushing bucket.
The Viper VPCH 21 is a one drum crushing bucket with a 40 rev/m, with its large 700mm drum with hard metal tips crushing the material to be processed against the counter teeth. Using the bottom grid, the crusher is able to reduce the fragmentation from standard 0-150mm to a minimum 0-60mm.
T. Mäkelä Oy’s VPCH 21 was able to produce material at approximately 94tph, which Viper claim is double the production rate of conventional crusher buckets. As well as reducing the concrete, any 12mm rebar fell through the bucket apertures and did not cause any delays. In rare cases when the steel bar bent around the tooth, it proved easy to remove it by counter rotating the drum.