Self-drilling hollow grouting anchor an overview of self-drilling hollow grouting anchor is the crown of the tunnel, at the wall and invert slope, such as the installation of deep foundation pit side wall at a supporting tool. This kind of anchor and shotcrete work together to form a ring bearer arch, soil nailing, micro piles, rock anchors, resulting in capacity. For fault, weathered rock, backfill layer, sand stone and other hard to clip into the hole of the complex formation. In the slope, deep excavation, tunnel advance support systems and high stress, large deformation of roadway deformation control and other projects with excellent results, because of its easy construction, for repairs, grab speed engineering is the preferred anchoring material. 2, the product consists of: a hollow grouting anchor body, alloy drill, grouting stopper, exhaust pipes, pallets, nuts and connection bushing composition (see figure). Hollow grouting anchor rod: the alloy material, for the whole hollow threaded bolt. Self-drilling anchor head: the alloy steel, there are cross-shaped, ball gear type. Pallets, Nuts: prestressed external locking fasteners and delivery components. Pallet with a vent. Exhaust pipe: plastic pipe through the vent fixed on the pallet on the pallet, placed on one end of the other end of drill hole depth outside. According hollow anchor bolt installation method used in conjunction with. Grouting stopper: rubber auxiliary materials to improve the grouting effect. 3, product specifications and technical parameters: Model (self-drilling) mechanical index rod bolt ultimate tensile bolt hole diameter not less than the diameter threaded rod Standard length direction of the maximum drilling depth kn mm mm L mm SD25A 210 25 42 2.5 / 3/3.5/4 / 4.5/5/5.5/6/8 15 meters above SD25B 180 25 42 SD27A 250 27 42 SD27B 230 27 42 SD29A 300 29 46 SD29B 240 29 46 SD32A 310 32 50 SD32B 250 32 50 SD32C 390 32 50 SD38A 450 38 75 SD51A 650 51 110 * bolt mechanical index and technical parameters can be changed according to user needs 4, construction specifications: 1, bolt installation, or a variety of different functions should be carried formation for hole collapse easily broken strata, then use self-drilling anchors, anchor body is its drill pipe, alloy steel fitted in the front drill rig will be set according to the length of bolt segmented side continued grouting cement mortar, the bolt is fully anchored in the formations. 2, grouting slurry with water, its water-cement ratio in between 0.40 to 0.55; if with cement mortar should be 1 part cement and 1 part sand and proper mixing together water, cement ratio between 0.35 to 0.45 in , grout consistency perfusion upward vertical hole should occur without sag. 3, anchor drill should be set up to the required depth of the hole should take advantage of all the surface dust debris hydraulic or pneumatic drill to clean up the grout grouting material from the bottom bolt perfusion; downward or horizontal direction toward perfusion , grout filled out, with its quick-drying cement mortar to seal openings to be 5-10 minutes and then put on pallets, and lock nut. As the need for a second fill slurry, the pressure is controlled at 15-45BAR; when facing perfusion slurry ground terminal bolt can be fitted with grouting stopper to waterproof mud extravasation. In principle anchor installation of about 24 hours, should tighten the nut and plate. Pad surface must be sprayed concrete, or rock leaving it at irregular shapes, can also be transmitted to the bolt bearing capacity even without making the bolt bending stresses. 5, the product advantages: 1, drilling, grouting, anchoring at once. 2, bolt international standard waveforms with continuous thread, anchoring strong rally from 100KN-1800KN. 3, without the use of casing, use grout reinforcement compaction grouting hole wall, cures water fall. 4, self-drilling anchor while drilling has extended features, the right to adapt narrow zone construction. 5, can be used with a variety of drilling rig, such as: 7655, jackhammer, YT27, YT28, Ingersoll Rand Bolter, no anchors, Luoyang and other rig factory rig.