1. Design basis and purpose of tunnel drilling rig

The deep prospecting design is based on the characteristics of the known ore body extending to the deep, in order to carry out the prospecting principle. Objective To expand the known results, find the blind ore body, obtain the basic reserves, and provide the design basis for the deep development of the mine.

2. Orientation and inclination design

In the deep prospecting work, the design of the perforated tunnel, the orientation and inclination of the borehole, which are mainly arranged in the middle plane, are determined according to the shape and occurrence of the orebody. Therefore, the drilling chamber is arranged in each channel and the fan-shaped hole is used to control the ore body. Generally, the main ore-bearing layer (belt) shall prevail.

3, the construction of drilling technical requirements

(1) The core recovery rate of the whole hole must be > 65%, and the recovery rate of the rock layer and the rock layer top and bottom (within 3-5 meters) must be > 80%.

(2) The design of deep drilling hole depth > 300 meters, drilling azimuth, and drilling inclination, within the range of 0-300 meters allowed azimuth does not exceed 2 degrees of the design orientation, drilling inclination allows drift within 2 degrees, drilling center location allows offset exploration line distance 1/4.

(4) Drilling azimuth R inclination measurement oblique hole provisions, every 50 meters oblique azimuth measurement, straight hole 100 meters oblique measurement once, instrument ZJL-42 compass, in the same hole depth position, the two instrument azimuth difference shall not exceed 4 degrees, inclination difference shall not exceed 2 degrees. Take its average value, if it exceeds the error, re-measure until it meets the specified requirements.

(5) Hole depth verification, the hole depth correction is required every 100 meters or the mine location, the error size is executed according to 1/1000 standard, the correction is carried out for those who exceed, and the correction is not required for those who do not exceed.

(6) Strict implementation of core drilling procedures

(7) Make a timely record of simple hydrogeological work, record the location of leakage and gushing water, and the location of karst caves encountered during drilling.

4. Safety measures for drilling in the pit of tunnel drilling rig

(1) Where the vein tunnel is used for deep drilling, the drilling chamber specification is 2×2 meters (width and height). Along the layer and through the vein must be shotanchor support, through the vein tunnel slope Angle of 3‰, and drainage facilities, the exploration roadway > 200 meters through the vein, must ensure that the feng shui and electrical facilities are complete, when designing the exploration tunnel, consider the design of ventilation measures in branches to ensure smooth ventilation.

(2) The construction of the drilling tunnel, safety personnel timely inspection, found that the tunnel collapse, roof fall, serious block and poor ventilation, hypoxia, closed air, must immediately stop the construction, withdraw personnel, to prevent accidents.

(3) The borehole is determined on the surface, the possibility of technical construction must be taken into account, and the hole location is required to be flat (to avoid steep cliffs, ponds and areas prone to flash floods and debris flows).