Failure and maintenance of the dth hammers

DTH Hammers Failure and Handling

1、Brazing head with broken wings.

2、Newly replaced brazing head with larger diameter than the original one.

3、Displacement of the machine or deflection of the drilling tool in the hole during rock drilling.

4、The dust is not easily discharged in the area with mud and rocks.

5、Falling stones or large fissures or cavities at the wall or hole opening during rock drilling.

6、Operational negligence, when stopping drilling for a long time, not blowing clean rock powder and not lifting the drilling tool, so that the dth hammer is buried by rock powder.

A piece of seamless pipe with a diameter similar to the diameter of the hole, filled with butter and asphalt, can be connected to the drill pipe to enter the bottom of the hole and take out the broken wing at the bottom of the hole, and blow the rock powder at the bottom of the hole before salvaging. For the more serious ones, use extra torque or use auxiliary tools to help lift and make the drilling tool rotate, then you have to give gas while lifting the drilling tool until the fault is lifted.

The temperature difference between the bearing and housing mounting position depends on the grade of interference fit and bearing size. Under abnormal circumstances, the temperature of the bearing is higher than the temperature of the shaft 80 to 90 ℃ is sufficient for the installation. But never let the bearing heating temperature more than 125 ℃, because then the bearing material will produce metallurgical transformation, diameter or hardness changes. Must avoid local overheating, especially not with open flame heating bearings. In the installation of the heated bearing to wear clean protective gloves. The use of lifting (hoisting) machinery can facilitate the installation. Push the bearing along the shaft to the installation position, so that the bearing does not move, push pressure until its fit is solid.

DTH Hammer  Maintenance

1、Because the joints and connectors of the dth hammers are right-handed threads, the dth hammers should always be kept right back during the drilling work.

2、When opening the hole, the minimum impact and propulsion force should be used to make the drill enter the rock formation smoothly.

3、It is important to match the propulsion force and the weight of the drilling tool, and the propulsion force of the thruster must change with the weight of the drilling tool.

4、The rotary speed usually adopted by the dth hammer is generally 15-25rpm, the faster the speed, the faster the chiseling speed, but in hard rock, the speed should be reduced in order to ensure that the drill bit is not overly worn.

5、Because plugging block and cavity may lead to stuck drill, so the dth hammer should be used to blow strongly and clean the bottom of the hole regularly.

6、Reasonable lubrication of the dth hammer should never be neglected, otherwise, it will accelerate the wear and tear of the impactor or even cause damage.

7、In the process of connecting the rod, rock ballast and various impurities will fall into the impactor, so the loose threaded end of the drill pipe must be covered to ensure that the drill pipe does not stick to rock ballast and dust.

Check the machine after each work, and deal with any problems immediately.


Post time: Sep-13-2022