Grab drilling

Chisels are used when drilling in very hard soils or rock and for piercing through drilling obstacles. They can also be used in cohesive soils for pre-cutting in order to be able to penetrate better with a piercing tool afterwards. The cutting edges of all LEFFER chisels are made of high-strength steel (Hardox 450). This guarantees high wear …

LEFFER’s scissor grab is a top-of-the-line universal drilling grab that has proven itself under a wide variety of requirements. Instead of using rope pulleys, this grab closes with a scissor system that operates with very little wear. A pre-tensioned spring is used to open the buckets and also ensures that adhering drilling material is …

For partially or uncased drills and/or when vibration-free drilling is required, the hydraulic spherical grab is used. Several hydraulic cylinders in the body of the grab provide high closing torques. In combination with its large dead weight, this ensures a constantly good filling level of the grab buckets. The hydraulic rotary drive allows …

The drilling and construction progress in projects depends not only on the machines used, but also quite significantly on reliable tools. For cased pile foundations, a robust drilling grab is essential. LEFFER has developed three robust digging grabs with high impact force for sinking boreholes in rocky, rolling soils and for working under water …

To increase the performance and improve the flexibility of our casing oscillators and casing rotators, separate hydraulic power packs adapted to our machines can be used. We attach great importance to components from renowned manufacturers in order to be able to guarantee trouble-free operation and the best possible availability of spare parts via …

Hydraulic oscillators are used when the torque of conventional drilling drives is insufficient or the use of rotary drilling rigs is uneconomical, for example in the case of large drilling depths or high casing friction due to the subsoil. Furthermore, it is used when the pull-back force of the carrier is not sufficient for pulling the casings. …

When concreting there is a risk of the concrete segregating in the downpipe. To ensure a safe concreting process, LEFFER has developed a special HD concreting tremie pipe system: The tremie pipe joints we have designed can resist very high tensile forces, which prevents the concreting pipe string from tearing off, even in case of very long pipe …

Decades of practical experience are incorporated in the design and continuous further development of our cutting crowns. For continuous drilling, the tooth system, i.e. tooth shape and number, contact pressure and the corresponding free cut must be correctly selected. The geology of the ground determines the design of the cutting teeth. Taking …

For cased boreholes from a depth of 35 m and a diameter greater than 1500 mm, LEFFER HD has drill pipes in its portfolio that meet the requirements for particularly large drilling depths. Reinforced pipe connectors with backlash-free, conical pipe screws and greater wall thicknesses reduce wear on the drill pipe connectors and also ensure reliable …

For cased boreholes up to a depth of 35 m, LEFFER offers double-walled drill pipes with a usable length of 1 m to 6 m. Our low manufacturing tolerances for diameter, roundness, and straightness pay off on the construction site. Precisely fitting pipe connections ensure quick, straight positioning, screwing, and optimal power transmission. The …