Strength Design and Analysis of the Grouting while Drilling Equipment’s Sleeve

Abstract

According to structure and working-condition of the grouting while drilling equipment, sleeve's compressive strength and torsion strength are calculated with elastic theory, which are simulated and verified with FEA Software. The results indicate that its maximum internal stress exceeds the elastic yield limit at 30 MPa external pressures, and that the sleeve is working with risk in 3000 m underground soft coal. With Prandtl stress function method, the calculated shear strength in the sleeve's small end is far more than the material's shear strength due to 1500 N•m torque, the small end is stress concentration area and it can't meet the requirement. Finally, sleeve's theoretical work external pressure is calculated as 29.8 MPa and its axial deformation is about 0.2 mm, with radial deformation level at 0.03 mm, which can be referenced to tolerance design in the assembly.