The causes of equipment vibration are described in "Basic Conditions for the Main Body of the Rock Rotary Drilling Rig
". The vibration hazards are as follows:
1 The structure of the equipment accelerates under the action of vibration, and the structure has premature fatigue failure.
2 Because of the uncertainty of the vibration direction, the structure of the rig is more complicated to load, and excessive triaxial force is formed inside the structure, and the equipment is more easily destroyed.
3 Due to the excitation, superposition and depletion of vibration, many structures change from static load to dynamic load, and most of them are impact loads, which puts higher requirements on equipment.
4 Accelerate the development and growth of tissue defects, such as the weld microcracks and the transition layer of the soft zone of the hardened zone in the heat affected zone, the internal defects of the material, the micro defects of the heat treatment, etc., which will absorb energy from the vibration to develop and grow.
In order to reduce equipment damage and accidents caused by vibration, we should design and grow the rock drilling rig according to the following points: 1 Calculate the structural reliability from the angle of dynamic load and fatigue.
2 Strictly select materials, select suitable processing technology and strictly implement them.
3 Reduce the application of structures that are prone to failure in vibration (eg, screwing).
Suggestions on the construction of rock drilling rigs
1. The effective service life of the tool is the most important factor affecting the drilling efficiency and economy. The qualified pick (or tooth) must be selected.
2. It is necessary to select a Drill Pipe
and several drill bits that are well matched with the project.
3. Different geological methods should be adopted to drill geology with different lithology.
4. Control the depth of each drilling, master the method and timing of cleaning, and the cooling of the tool.
5. The drilling efficiency of the rock formation is 1/20~1/5 of the soil layer, and the equipment and tool loss is much larger than the soil layer. It is necessary to select the project with reasonable construction cost.