Research On The Drilling Parameters Of Rotary Drilling Rig Considered With Drolling Rock Speed And Life Of The Power Head Gear

Rotary Drilling Rig, as a high-tech modern piling equipment, and taking its advantages at drilling efficiency, drilling depth and diameter, energy saving and environmental protection and many others, has been widely applied on the fields of road, bridge, architecture construction and so on. However, acting as an essential indicator to evaluate the performance of the equipment, the capacity of drilling into the rock has presented itself as a tough question, while there is rather little research involving it at home and abroad. Choosing reasonable drilling parameters for ensuring the economic benefits of construction to reach its maximum is necessary for this high input-output piling equipment, taking drilling speed and the life of the power head gear into consideration, because unreasonable drilling parameters of rig will seriously affect economic benefits of construction of rig. Therefore, based on the study of the load characteristic while rig drilling rock, the reasonable drilling parameters of rig was gotten by the analysis of the influence of drilling parameters on the drilling speed and the life of the power head gear, and a set of electro-hydraulic proportional control program was designed to ensure that rig drills steadily on the reasonable drilling parameters point. The main contents are outlined as follows:1. Based on the research of single Conical Bit while cutting rock, also combined with structure and operating characteristics of the Short Helix Bit of Rotary Drilling Rig, a load model of Short Helix Bit was built and the mathematical expression for drilling speed of rig was derived, the discipline of drilling speed changing by contact strength of rock and drilling parameters was revealed.2. According to the load of rig while drilling rock and the time-varying incentives within gear system, the power head gear system dynamics model was established and the meshing force of a node of the pinion was obtained. Also the dynamic contact stress was gotten according to the Hertz contact theory, the discipline of contact fatigue life of the node changing by drilling parameters was received by fatigue life analysis with Miner cumulative damage theory.3. Comprehensively considering the influence of drilling parameters on the drilling speed and the life of the power head gear, and aiming at the largest economic benefits of construction, this research commits to obtain the most reasonable drilling parameters of rig while drilling rock A set of electro-hydraulic proportional control program was designed to ensure that rig drills steadily on the reasonable drilling parameters point through theoretical modeling of the pressurized circuit hydraulic system and simulation by AMESim software.4. According to the data from the geological exploration units, the experiments on the same device in two different construction sites were conducted by using above theoretical results of the research, the accuracy of drilling speed mathematical expression for Short Helix Bit of Rotary Drilling Rig when normal drilling at full power and the rationality of the electro-hydraulic proportional control program was verified by the comparison of theoretical and experimental results.Some data and rules with a certain theoretical and practical value have been obtained through the research of reasonable drilling parameters of Short Helix Bit of Rotary Drilling Rig while drilling rock, which not only laid a solid foundation for the follow-up research and the exploitation of new products, but also played a guiding role in the actual construction.