Sandvik Construction Doublescreen-duo guarantees high output for Kieswerk Lucht
The family owned company, Kieswerk Lucht, has been quarrying sand and gravel across the North German district of Dithmarschen for over 100 years, with its main operation being located in Buchholz since 1998. Here over 250,000 tons of fine sand is produced each year, with two Sandvik Construction QA340 tracked mobile Doublescreen units, with additional stockpilers, all supplied by authorised distributor Oppermann & Fuss, playing a key role in the dry production process.
Focused material production
Since its opening in 1998 Kieswerk Luchts' main site is located in Buchholz, and is now the company's major sand and gravel operation. Covering approximately 13 hectares, with an additional further 30 hectares of excavation area approved at the site, plus further reserves, the future for this family-owned company looks secure. Now run by the 5th generation of the family, Jens and Reimer Lucht, materials processed at the site are being used as filler throughout the Dithmarschen area, supplied to companies within a 25 kilometre radius.
Of the material found at Buchholz only 5% of the standing raw material is gravel, which has proved particularly useful in construction applications as it is nearly completely free of organic contaminates. This has allowed the Lucht operation to be focused on economical dry screening technology, with the main products being unwashed sand fractions of 0/2 mm and 0/3 mm. Luchts' refrains from further processing of the gravel fraction as the larger uncrushed road gravel screening fractions complement their product range, being further supplemented by externally purchased products, for example sub-base, which is then stored at the Buchholz site.
The processing of the material is only part of the production requirements, with any movement of material within the site being handled by two 5m³ wheel loaders, which are used across the various different levels of the quarry. This is an important facet of the operation, as each quarry face can rise up to six metres, whilst reaching down 25 metres. Fortunately the loaders are able to utilise calibrated weighing equipment for use in quarrying, handling and loading, and are assisted by a tracked excavator which is mainly used for slope stabilisation and modelling.
High capacity screening solution
Material production at the site is undertaken by mobile screening plants, with the Lucht operation having realised the advantages to be gained from this processing technology for a long time. Initially the company used wheeled equipment, later investing in tracked machinery to allow for easier positioning without additional ground preparation. Even though the specific screening production requirements at Buchholz are not particularly demanding, plant mobility is essential, as the year round operation is adjusted to ensure high productivity with most economical results.
The current screening operation at Buchholz is undertaken by two Sandvik Construction QA340 double-deck Doublescreens. These machines have proved pivotal to the operation as they are able to process 500 tph of gravel, and the 350 tph of sand, which are both required during high production peaks. The first QA340 was purchased in 2011, with Kieswerk Lucht taking delivery of the second machine at the end of 2012. Both screeners were supplied by Sandvik Constructions' authorised distributor in the area, Oppermann & Fuss, who also provides full aftermarket support.
The senior member of the family responsible for the business, Reimer Lucht, states that the main reason for purchase of the QA340s is the patented Doublescreen technology used by the screener. This allows the screening performance of the 27 ton plant to adapt exactly to the given quality, and conditions, of the raw material. Reimer explains; "We purchased the first Doublescreen plant back in 2005. Specifically in sand applications the two separate screen boxes, with separate drives, excel with a high acceleration of the material. And according to the material's condition we can easily adjust the first screen box to a steep angle and get even higher efficiency."
Efficient and economical processing
The QA340 is certainly ideal for the tasks set for it by Luchts; the total screening area measures 5 x 1.5 m on both the top and bottom deck, with operational flexibility being maximised through the machine possessing the facility to change the screening media, or be serviced, through the hydraulic raise functions of the main and side fine conveyors. Luchts' QA340s currently operate with a 40 mm square mesh on the top deck, and a 3 mm Harpscreen on the bottom deck, with the vibrating remote controlled double deck vibrating grid (on both machines) being fitted with a 80 mm square mesh on the 7m³ feeder.
The two QA340s are able to provide an average sand production of 350 tph, producing fractions of 0/2, 2/35 and 35/80 mm. Additionally, through the use of separate stockpilers, Reimer Lucht is able to "buffer" these high production rates; as he explains - "At 350 tph combined feeding and handling with single wheel loaders is not economical, the screen runs empty too quickly." Thus use of this additional equipment allows for the stockpiling capacity of the end product (0/2 mm), to be up to 10,000 tons being facilitated by the 24 m stockpile, which also possesses a discharge height of 10 m, and is located at the edge of the 6 m face on the lower level.
A major additional benefit for Luchts' operation has been the improved fuel efficiency derived from the Sandvik screeners. Reimer Lucht has assessed the long term average fuel consumption of his Sandvik QA340 to be an economical 15 litre per hour (approx.) for both 75kW plants. One unit works nearly "stationary", with only two movements per year, whilst the second unit more frequently follows the excavation activities, or switches position after a short screening media change, depending on the required production of defined gravel fractions. "If I additionally calculate the 5 litre per hour consumption of the stockpiler against the 20 litres per hours of the wheel loader, my whole operation definitely becomes more efficient." Adds Reimer.
Providing Luchts with approximately 250,000 tons of material production each year, the exclusive use of Sandvik Construction screening technology is a vote of confidence in not only the equipment, but also for the Sandvik dealer and service partner, Oppermann & Fuss. Located in Quickborn, approximately 80km from Buchholz, the company has forged a five year partnership with Kieswerk Lucht, which is, according to Reimer Lucht, principally based on the high quality of aftermarket provision.
Key to the high levels of aftermarket customer care is the regular service (or larger repairs) delivered by the mobile Oppermann & Fuss Service operation. However, more routine maintenance is easily undertaken by Lucht staff as each screener is supplied with its own service container, in Sandvik colours, with all necessary small parts, lubricants, fluids and tools included. Thus the combination of screening technology from Sandvik Construction, the industry knowledge and service expertise of Oppermann & Fuss, has allowed the forging of a successful partnership allowing Kieswek Lucht to operate at high levels of efficiency and productivity.
For further information, please contact:
Marketing Communications, Mobile Crushers and Screeners
Tel. +44 (0) 1283 818164
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