Dressta machines are playing a leading role in the continuing success of a leading Polish sand and gravel mining firm, reports Marek Stakowski.
Poland’s sand and gravel reserves amount to over 9.7 billion tonnes, with the greatest amounts found in the regions of Mazowieckie, Wielkopolskie, Lubelskie, Lódzkie and Podkarpackie.
One of the country’s biggest sand and gravel mining companies is Piaskarz, which has been active in the construction market since 1988. Having started out as a limited company, it went public in 1990.
“We mainly do extraction, production and sales of minerals for the construction and transport sectors,” says Ryszard Kuciel, CEO of Piaskarz. “Our company has five production plants in the Mazowieckie region. These are our four sandpits in Warsaw and a mining plant in Osówka near uromin. In the sandpits located in Warsaw, we extract sand from the Vistula on the left side of the river in the Bielany and Kpa Zawadowska neighbourhoods, and on the right side in Tarchomin and Miedzeszyn neighbourhoods.
“For sand mining we use a high performance dredger,” continues Kuciel. “The resources sucked up from the river bed are transported to the river bank by the dredgers and stored. Using this technology doesn’t affect the natural environment in a negative way: the dredgers work at noise levels that are not excessive, and the transported sand does not cause dusting. In the mining plant located in Osówka the mined sand and gravel are extracted from dry deposits using high performance excavators and wheeled loaders.”
The Piaskarz fleet includes 27
“The material excavated from the river bed by the suction head is pumped at pressure to the bank as a mixture of water and sand, before being transferred to the storage area,” says Krzysztof Wałachowski, Technical Director at Piaskarz. “The sand storage location is divided into two fields: one contains only wet sand, from which we drain the water, and the second receives the already dry sand, which has been drained through the use of gravity. Through the prepared drainage system of specially formed trenches with an appropriate slope, water drainage can take place. Excess water and surface contaminants are then returned to the river. The drains are made by the Dressta bulldozers and wheeled loaders produced in Stalowa Wola, which are also used to load the sand onto stationary or mobile mesh in order to separate the supergrains from potential contamination.”
In the four sandpits and single gravel pit there are 16 wheeled loaders in total. These machines are popular both internationally and domestically, with an engine power of 162kW, bucket capacity of 3.4m³ and operating weight of 21–22tonnes. The Dressta machines are constructed entirely in Poland, and the company has been successfully producing these machines in Stalowa Wola since the mid-1970s. Thanks to their optimal technical specifications, simple construction and use, reliability in any working conditions, and the possibility of using multiple working attachments, these machines are said to have become a highly desirable Polish export in the industry. More than 20,000 wheeled loaders with parallel 2Z loader linkage have been manufactured at Stalowa Wola since the mid-1970s. Up until the year 2000, they were powered by Leyland licensed engines and called L-34 wheeled loaders. Since then they have been equipped with a
At Piaskarz, the L-34 is the loader of choice. It was produced between 1997 and 1998, and was followed by the 534C from 2005, and the 534E from 2007–2014. The oldest machines have worked over 20,000 hours, while the clocks of the newer models show between 7,000 and 10,000 hours. Their main function is loading the extracted material onto transport vehicles, crushers or conveyor belts. Additionally, in the winter the loaders are used to remove snow from access roads to the sandpits and from local roads.
“Snowstorms and blizzards sometimes create snowdrifts as high as three metres,” says Wałachowski. “Then our loaders are the only hope to guarantee that our clients can reach the plant and safely load the material. Our products include river sand, sieved and bagged sand, mine sand with a fraction of 0-2mm, gravel (gravel mixture) with a fraction of 2-16mm, fractioned gravel 2-8mm and 8-16mm, sand-gravel mixture with a fraction of 0-16mm, a blend of crushed aggregate with fractions of 0–31.5mm, and unsorted lump or bulk material. The latter is a native soil similar to sand and gravel which, thanks to good filtering, mechanical characteristics and high load capacity, is a material that is often used in construction as the basis for foundations, and in road building it is used for the drainage layers of road embankments.”
A wide range of additional working accessories used in this loader makes it possible to use it for various tasks according to its user’s needs. It features 10 types of buckets, including ones for rocks (2.7m³), multipurpose (3.4m³), coal (5.7m³), or agriculture (5.6m³). The loader can also be equipped with a special bucket for mining pulps, a hydraulic grapple for loading tree trunks or pipes (load capacity up to 5.5tonnes), and adjustable forks or forks for rock transportation (up to 7tonnes). The quick coupler and the central lubrication system are installed as additional accessories when ordered by the client.
The 534E loader is powered by the reliable QSC8.3 series of engine from Cummins, which features 169kW of power and is compliant with the EU Stage III A standard. The advanced technology of QSC raises the engine’s efficiency and provides more torque. Thanks to the perfect combination of electrical steering and a lasting block construction, this engine is able to cope even in the toughest working conditions. Extended service intervals, better start-up in low temperatures and quiet operation are said to guarantee operator working comfort.
The ROPS/FOPS type cabin located on the back frame provides excellent visibility for the operator, and the ergonomically spaced operating handles and control instruments reduce his effort. The seat features height and angle regulation, so it can be moved forward and backwards with the armrests and headrest to ensure a comfortable position.
All loaders from the 534 series used at Piaskarz have a central lubrication system and modern material scales with an electronic display.
Piaskarz’s 11 Dressta crawler dozers are on license from US firm International Harvester. They are used for removing caprock, creating dykes, transporting the extracted materials to the crushers or mobile and stationary screens. The crawler dozers comprise two TD-25C models with 149kW engines, three TD-15C models with 103kW engines, one TD-15E model, with a 129kW engine and 12,000 hours of work behind it, and five TD-15M Extra crawler dozers. These latter five models are the latest models of Dressta mid-sized bulldozers, which have been gradually purchased by Piaskarz since 2007. They have already worked between 5,000 and 7,000 hours.
“One of the main rules at our company is to ensure the machines are maintained to an optimal condition,” stresses Wałachowski. “They always have to be operational and ready to work. That is why specific machines have been assigned to a given operator – one machine, one operator. This guarantees its care and timely registration for service inspections. We can always count on support from the technical and service department of Dressta and its distributor regardless of where he is or where the machines which require intervention are located.”
WHEELED LOADERS
6 x L-34 (HSW)
1 x 534C (DRESSTA)
9 x 534E (DRESSTA)
CRAWLER DOZERS
2 x TD-25C (HSW)
3 x TD-15C (HSW)
1 x TD-15E (HSW)
5 x TD-15M Extra (DRESSTA)
EXCAVATORS
1 x DEMAG H-50 hydraulic excavator
1 x VOLVO EC-60 hydraulic excavator
1 x CATERPILLAR 235 hydraulic excavator
SCREENING
3 x TEREX FINLAY 683 (mobile)
3 x TEREX FINLAY 693 (mobile)
3 x ŁZG Łczyca S.A. (static)
CRUSHERS
1 x HAZEMAG impact crusher
1 x PREROVSKE STROJIRNY SY 1044 cone crusher
The Dressta TD-15M Extra is said by Dressta to be one of the best and most popular machines in the industry thanks to the wide range of accessories available for the four versions of the undercarriage - standard, LGP, LT and WT. The construction of the bulldozer ensures perfect effectiveness and work comfort for the operator. It is powered by a Cummins QSC8.3 series 142kW engine, in line with the EU Stage IIIA exhaust emissions standard. Advanced electronics ensure a strong performance and higher torque. Prolonged periods between inspections and quiet work provide a high level of comfort for the operator. Also, the comfortable, sealed and soundproofed cabin with an air recirculation system provides a comfortable work place. The hexagonal cabin is isolated from the engine compartment and can be detached, which allows for easy transportation.
The pneumatically powered and regulated operator seat with armrests is equipped with a lap seat belt. The seat can turn 14° right which provides for good visibility of the ripper. The joystick on the left side is for controlling the gearbox and the turning system. With the use of levers you can change the driving direction, conduct a turn, change a gear, or choose a high or low range in the steering mechanism. Drive speed preselection and automatic gear reduction ensure working comfort and high efficiency. Thanks to these, the operator doesn’t have to pay much attention to the manual shifting of gears. The lever to the right of the seat is used to control the movement of the blade – lifting, lowering, tilting, tipping or turning if using the universal blade. Meanwhile, the second lever controls the raising and lowering of the ripper.
The TD-15M Extra bulldozer can also be equipped with various types of blades and two types of rippers: single-shank or multi-shank. The most popular blade among users is the Semi-U blade with an STD or LT undercarriage capacity of 5.7m³, rising to 5.95m³ when used with WT undercarriage. This blade provides good ground penetration and enables the bulldozing of large quantities of dirt thanks to its construction, and it is also equipped with cylinders, which enable tilt and tilt/pitch options. Meanwhile, the angle blade with a capacity of 3.8m³ when used with an STD or LT undercarriage is an ideal tool for bulldozing extracted material, filling in ditches or levelling the terrain. The blade’s tilt is achieved with the use of two hydraulic cylinders. The 6-way blade with hydraulic steering provides 3.6m² WT undercarriage capacity, and 4m³ when deployed with LGP undercarriage. It is used for light work, such as levelling terrain and paving the material. Meanwhile the straight blade, with a capacity of 3.6m³, is only used with the LGP undercarriage and track plates with a 940mm width. It is designed for work on muddy and wet ground. This blade is equipped with a hydraulic tilt which is helpful for the final formation of the terrain.
“We buy original spare parts for our machines, which guarantees safe, reliable and efficient use,” explains Wałachowski. “The purchase of original spare parts leads to lower maintenance costs and lengthens the machines’ operating lives. My task is to maintain the company machines at full standby with a reasonable cost dedicated to purchasing spare parts. We often found that the spare parts offered by Dressta and its distributor are produced in compliance with the same norms as those applied to the production of machine components.”
