Study On Vibration Characteristics Of DTH Hammer Of Rotary Drilling Rig

Due to the large torque and large diameter of the hole,the rotary drilling rig has been widely used in drilling engineering,but the conventional drilling tool is inefficient in the process of drilling hard rock.In order to solve the problem of hard rock drilling,the drilling hole can be effectively improved by the use of the down-the-hole hammer and the rotary drilling rig.In order to study the vibration characteristics of the rotary drilling boring machine during the drilling process,this paper combines the Xuzhou pipe gallery project and the Shandong Lunan high-speed rail pile hole project to drill the kinetic model of the drilling boring machine and the down-the-hole hammer.The vibration test system,the vibration response analysis of the down-the-hole hammer and the extraction of the characteristic parameters,and the evaluation of the application effects of two different types of dampers are studied:Based on the Ritz series method,a dynamic model including the part of the rotary drilling rig damper,the down-the-hole hammer drill string,and the lifting wire rope is established.The effects of the factors related to the vibration of the DTH hammer on the displacement field equation and dynamic load of the drill string are studied.The vibration characteristics of the DTH hammer during the drilling process are analyzed.The Ritz series is verified by the model.Convergence,the modal frequency information of each order is obtained.Based on the virtual instrument technology,the submersible hammer vibration test system of rotary drilling rig was constructed.The selection and design of the hardware part of the test system was carried out,including the selection of main components such as sensors,acquisition cards,and flow meters,and the design of some hardware circuits.Based on Labview and Matlab,the test software was developed to realize the modular function combination,and the field test data acquisition and signal offline analysis were completed.The debugging of the main functions of the experimental hardware was completed.The test system was applied to the field experiment and achieved good practical results.Combined with EMD and Laplace wavelet correlation filtering method,the time-frequency characteristic parameters of the shock response of the down-the-hole hammer are extracted.Through simulation and experimental analysis,the DTH vibration shock response is a transient attenuation signal including multiple frequency components.Firstly,the multi-order modal response components generated during theDTH drilling process are separated by EMD,and then the Laplace wavelet correlation filtering is used to extract the key characteristic parameters of the single modal signal.The practical effect of the DTH damper is evaluated based on the wavelet packet energy band decomposition method.Through the correlation of amplitude ratio,vibration transmission rate and other related indicators,the signal is multi-band decomposed by wavelet packet decomposition,and combined with the application conditions of the damper,the effects of two different types of dampers are evaluated.