Three Accidents Prone to Crawler Rigs?

Jul. 10, 2020

Crawler Mounted Drilling Rigs drilling problems-drill bit and drill rod buried

① The complexity of geological structure. Because the drill bit and the drill pipe are deep to work 30-50m deep, and the geological structure is complex, there are sandy clay layers, hard weathered rocks, and seemingly loose iron plates with great friction Sand, the most common is a mixture of pebbles and fine sand, which causes an uneven force on the drill bit. When the construction site encounters such a complex formation, the drilling speed and the scale of each drilling should be slowed down first, and the drill rod should be reversed a few more times before lifting the drill bit.

② Mud quality. Mud quality is one of the most important factors affecting pile hole collapse, and whether the pile hole collapses is one of the most direct reasons for the bit and drill pipe being buried. Therefore, the mixing mud must be prepared according to the ratio of bentonite: caustic soda: water = 1:1:50 to ensure the viscosity of the mud.

Crawler Mounted Drilling Rigs

Crawler Mounted Drilling Rigs

③ The mud should be injected into the pile hole in time. The mud after mixing should be added to the pile hole in time with the deepening of the drill rule, so that the liquid level to the upper part of the protective wall does not exceed 20cm, in order to increase the pressure of the mud on the pile hole, to prevent the pile hole from collapsing and burying the drill bit And drill pipe.

④ Master the scale of each drilling. In general, a drill with a diameter of 150cm does not exceed 1m per shot; a drill with a diameter of 180cm does not exceed 0.8m, and a drill with a diameter of 200cm does not exceed 0.5m. The drilling scale is displayed by the depth indicator in the cab. The operator should pay attention to the observation, and at the same time change the drill bit (generally divided into two types of earth drill and sand drill) according to the change of stratum. After the replacement, pay attention to lock the drill pin. If you can be cautious, the phenomenon that the drill bit and drill pipe are buried or stuck can be avoided.

Automatic Crawler Mounted DTH Drill Rig drilling problems-the main winch wire rope suddenly breaks

① When lifting loads such as drill bits, drill rods, and soil from the pile hole, gently pull up the main winch handle, and pay attention to observe that the value of the lifting tension meter generally does not exceed 20t; if it exceeds this value, the handle should be released, Then turn the drill rod in the opposite direction. Never use the quick button suddenly when lifting to prevent the instantaneous increase of the tensile force from breaking the wire rope.

② Pay attention to observe the number of broken wires and the state of stretching of the wire rope, and replace it in time when problems are found, to avoid the sudden winding of the main winding wire rope during work.

Problems with the drilling of the crawler rig-the auxiliary hoisting wire ropes are twisted together

The main function of the auxiliary winch is to put the test guide cage into the formed pile hole to detect the amount of lateral deviation of the pile foundation.

Loosen the vice when hoisting the wire rope slower. Losing it too fast may cause the rope to twist together and intertwine with each other; it will take time and effort to slam the rope again. Even if the rope is made and wound up again, the wire rope damage is also very serious. , Should try to avoid this situation.

On-site machine and personnel safety

① Due to the large size of the crawler rig and the narrow working environment, coupled with the noise generated by the engine, the visibility, and hearing of the operator's cab will be greatly affected, so for safety, idle personnel should stay away from this area when the rig is working, The operator can whistle to call or remind other personnel to pay attention.

② When the drill pipe is upright, the operator's field of vision should be widened. Be alert to high-voltage cables in the air in the work area to prevent collision and contact to avoid electric shock, fire, personal injury, or death.