have been designed in accordance wiht the latest technical know-how. Extremely sturdy construction gaurantees worth-while use on site. By means of exact statical calculations in conjunction with higher quality material, an optimum conformity of loads, weight and material strength is achieved. The internal welding stresses, not easily determined for the statical calculation, and which would affect the construction considerably, are eliminated by means of stress relieving prior to machining.
A prominent feature of the equipment is the clamping collar consisting of five links operating on the boring implement. The individual links surround the casing like a chain so that a constant surface pressure is exerted on the casing circumference. In addition, the large height of the collar (400 to 700 mm) prevents any damage to the casings. By means of easily exchangeable reducer pieces the oscillator can be converted, within a few minutes, to a smaller casing diameter. The collar opens uniformly and enables unproblematic insertion of the casing with the cutting shoe. Another advantage of the machine is the low height on the excavator side.
Considering the high costs involved in the failure of the machines on the construction site, the emphasis relies on a very solid construction.
HYDRAULIC CASING OSCILLATORS (VRM)
Accurate static calculations combined with a higher-grade material ensure optimum matching of load, weight and material strength. The residual weld stresses, which are difficult to detect for the static calculation, which significantly pre-stress the design, are eliminated by stress relief annealing prior to machining.
With easily replaceable reducers, the casing machine can be converted to a smaller pipe diameter in just a few minutes. The clamp opens evenly and allows easy insertion of Bohrrohrschneidschuhes. Another advantage of the machine is the low height on the excavator side. The excavator can be swiveled in a coupled state by 360 degrees. The attachment to the excavator itself is torque-resistant and guarantees a solid excavator stand, the transmission of the full rotational movement of 25 degrees to the pipe string.
HYDRAULIC CASING ROTATORS RDM UND RDM-M
The hydraulic full 360 degree turning casing rotators are economically used to construct bored piles with the full casing method under hard soil conditions. The continuous cutting of the hard ground guarantees a boring speed satisfying to-day's requirements, even for compressive resistance of up to 2500 kg/cm2.
The full 360 degree continuous turning of the casing minimizes the friction compared to the oscillating method allowing the casing to drill down to 100 m depth with the casing rotator machines.
The first casing is fitted with carbide bits which can be adapted to the requirements of the soil conditions offering major advantages when coring through hard rock layers or when constructing secant pile walls.
The full 360 degree continuous turning of the casing by powerfuil hydraulic motors eliminates the possibility of pile misalignment.
Beyond that, the casing rotators are especially suitable for the construction of full casing displacement piles because of the ability to apply very high torque, push down and lifting forces on the casing which is not possible with the known drilling rigs.
Hydraulic power packs powered by latest generation diesel engines are manufactured by LEFFER and matching the hydraulic piling equipment.
LEFFER power packs are designed compact, powerful and silent.
Only high end components are used, to ensure trouble-free operation and the availability of spare parts worldwide.
The hydraulic power packs are designed straight forward to ensure reliability and to ease maintenance, all components are easy to access.
The LEFFER power packs are available in a performance range between 45 kW and 429 kW, where hydraulic volumetric flows of up to 1200 l/min (320 gal/min) are possible.
Well dimensioned hydraulic filters and oil-coolers guarantee trouble-free operation even under adverse conditions.
As a matter of course, special customer requests can be considered, while laying out the power packs.
All questions on the purchase of an oscillator you can specify by phone in St.-Petersburg (812) 927-93-55 or on the application for firstname.lastname@example.org