A bucket isn’t just a bucket these days. There are now a variety of specialized models available to take on tasks well beyond digging and dumping. Particularly noteworthy are those designed to screen and/or crush materials in place. Prevalent in Europe, these attachments are starting to show up on more U.S. jobsites as contractors begin to recognize their benefits.
Apex Pipeline Services, Inc. is an oil and gas pipeline contractor working on a project for Marcellus Shale in West Union, WV. Started in April 2012, the job involves the placement of around 87 miles of gas pipelines. Apex is using REMU EX 140 screening buckets on its 21-ton Caterpillar excavators to backfill excavations.
The screener is a portable bucket with rotators turning both directions to sieve material while in use; larger particles are retained inside the bucket. The sieved material can then be reused on site for padding and backfilling.
Avoiding/reducing truck traffic on the pipeline site was very important for Apex Pipeline Services due to the very limited work space in the mountainous regions around West Union. Screening the material directly into the trench reduces truck movements. Use of the screener has also enabled the contractor to avoid purchasing new, fine material and transporting it to the work site.
“By screening on site, you save on both material costs and transportation,” says Sini Karjalainen, REMU. “On-site bucket screening increases the time that machinery is used for profitable work by eliminating downtime associated with waiting for the next truck.”
Screening buckets are available in a variety of types, sizes and configurations.
VTN Rotobec offers five models of rotary screening buckets for use on excavators from 7.5 to 38.5 tons. They’re available with a single-piece steel screen ranging in size from 3/4 to 3 in., and are suited for applications where materials from a demolition job are being used in new construction or where fill has to have specific characteristics.
Also available is the SB screening bucket, which screens material using 1- to 4-in. screens mounted longitudinally inside the bucket. Three models are available for carriers from 14 to 45 tons. This attachment is particularly suited for screening demolition material, reclaiming rocky ground and for quarry applications.
REMU USA also offers hydraulically operated screening buckets that utilize rotating blades to screen finer material out while retaining oversized material in the bucket. The attachments are available in .24 to 7.2-cu.-yd. capacities (SAE) and can be mounted on carriers up to 40 tons, including excavators, wheel loaders, backhoe-loaders and skid steers.
List prices for REMU screening buckets range anywhere from $13,500 to $80,000, depending on the size and setup. This can be quickly recouped by the time saved in separating materials on site. “In most applications, it is more effective and economical to screen materials first,” says Karjalainen. “The screening bucket is made to genuinely classify and separate materials.”
A screening bucket can be used to process existing soil into a finer product for use as fill or padding, which can reduce the volume of material that has to be trucked to and from the site. “With a screening bucket and the right blade design, it is easy to process different materials that have lumps or frozen clods,” says Karjalainen.
Blades may be available to convert the buckets for other applications, as well. “REMU screening buckets can be converted into a screener/crusher by replacing the blades with crushing and shredding blades,” says Karjalainen. “Furthermore, spiral rotators combined with crushing blades can effectively grind lumpy material. The spiral-shaped configuration also reduces needed power.”