Flexible mobility pays off
The new Destroyer 1113 has been deployed in the recycling process at the Danish company Kim Vind Maskinstation & Entreprenør since the summer of 2015 (Fig. 1). The intermediate version of Keestrack’s track-mounted impact crusher unit is a 49 tonne machine with a secondary screen unit featuring convincing practical and effective mobility, broad operational versatility and a high level of operational efficiency.
With a total of 17 employees and a pool of nearly 30 modern earth-moving machines, road building machines and civil engineering equipment, the 2001 founded company takes on projects within a radius of up to 100 km. Since 2008, the company has also been offering the recycling of waste building material and excavated soil material as part of its own construction or demolition projects as well as a subcontractor at external building sites and materials depots of other building contractors or large agricultural businesses (Fig. 2). According to proprietor Kim Vind, this work represents at least 20 % of today’s business. The company has been using a track-mounted 30 tonne jaw crusher to date and also a Keestrack Combo double-deck screen unit since last year, supplied and supported by Danish Keestrack dealer TNS Imex in Løgumkloster.
Within the context of the proven working relationship the Keestrack partner was also shortlisted in the summer of 2015 to provide a replacement for the company’s jaw crusher. “We had an early preference for Keestrack’s impact crusher technology for the operational and material requirements at Kim Vind,” TNS Managing Director Thomas Sørensen says. “We initially surprised our client with this somewhat, one reason being that high-performance crusher units are not particularly common in the Danish recycling industry, which is characterised by frequent relocations. While smaller systems for inner-city recycling offer the desired flexibility but not the required capacity that can reliably process more than 200 t/h.”
Kim Vind was soon convinced and opted for the first production model of the new Destroyer 1113 machines. “The order was placed in February – Keestrack customised the machine, as it does for all models with a multitude of options coming from the factory, to the individual requirements, and we were able to deliver by the end of May.” The Destroyer 1113 with the secondary screen unit und recycling conveyor installed weighs only 49 t in all (without secondary screen unit/recycling conveyor: 46 t). Together with the machine’s compact transport dimensions of 16.26 x 3.00 x 3.35 m), this means any relocation can be achieved quickly and easily (Fig. 3).
The material first emerges from 5 m³ charge hopper with variable vibrating pan feeder via an active double-deck primary screen to separate the fine particles, which are transported outside the crusher by means of a bypass or are stockpiled laterally. This minimises wear and tear and optimises the qualitative crushing efficiency of the impact crusher with an intake opening of 1050 x 800 mm (Fig. 4). The heavy build of the 1000 mm wide rotor with four impact bars (Ø: 1260 mm, weight: 5100 kg) and the high crushing area volume guarantee high production rates and a long service life of the equipment. Likewise, the direct-drive unit (rotor speed: 51-609 rev/min) has an equally convincing quiet operation while the machine is working.
A vibration chute beneath the crusher transports the crushed material gently onto the main discharge conveyor (7500 x 1100 mm), where the remote controlled hydraulically height-adjustable overband magnet separates metallic constituents. The optional single-deck final screen (screening surface: 3300 x 1500 mm) produces two fractions via conventional removable screen media, with the swivel-mounted recycling conveyor returning the oversize grain to the charge hopper or stockpiling it as additional final grain (Fig. 5). The optional double-deck module and upgradable mid-grade conveyor for a second value-grain size offers even higher added value in solo operations.
The entire machine is controlled and monitored by Keestrack’s SPS-based Relytec controller, which guarantees numerous function routines, clear on-screen information and optional wireless remote control, a high level of operating convenience and smooth operations (Fig. 6). The Destroyer 1113 sets further standards in terms of maintainability with large-scale steel casing for hydraulic operations and the unique lifting function of the main frame, permitting free access to the crusher outlet and discharge conveyor as well as the easy assembly/disassembly of the final screen or optional 4-axle dolly. With regard to the power unit, Kim Vind opted for the ECO-FS diesel-hydraulic system with a 298 kW Cummins diesel engine and load-sensing hydraulics, enabling fuel savings of up to 25 %. Like many other Keestrack machines currently available, the Destroyer 1113 is also available with ECO-EP and ECO-EP+ diesel-electric systems. In that case, the on-board diesel generator consumes up to 33 % less fuel – power supply entirely from the electricity grid (EP+) are reported to be 70 % lower and clearly reduce emissions as well.
With more than 500 hours of operation in the first five months since start-up, the Destroyer 1113 clearly had an excellent workload immediately after deployment. In the one-man-operation mode with a dedicated machine operator/excavator operator, the machine reliably achieved production rates of between 200 and 260 t/h during typical recycling operations with very diverse building rubble (input: 0/700; final grain size: 0/25, 0/40). Approximately 230 t/h has been recorded for gravel production from hardstone (granite/siliceous limestone, final grain size 0/40). Average fuel consumption to date of almost 50 l/h has been calculated.
“The switch to Keestrack’s crusher and secondary screen unit has enabled us to expand our range of services and our customer base. Today we are processing a broader range of raw materials and supplying higher-grade end products, regardless of whether we use demolished concrete, asphalt, natural stone or any other unspecified building material,” Kim Vind comments (Fig. 7). Even when used on construction sites, the Destroyer 1113 comes into its own when equipped with an additional hydraulically driven generator and compressor for small tools: “The final screen means we can actually often dispense with a machine, making it possible also to process smaller batches in solo operation.” In addition, a self-mounted fan for the air separation of light materials also enables us to handle the processed residual mass in a simple manner.
The Kesstrack Destroyer 1113 processed more than 100 000 t between June and December 2015, leading to a very welcome bonus in Kim Vind’s recycling operations, thanks in particular to its great versatility. Account is already being taken of the fact that the company will regularly have to deploy the jaw crusher too, which was actually earmarked as a stand-by machine.
