... drilling. Long spiral drill diameter of not more than Phi 800mm general, to import large drilling long spiral drill, spiral drill ... .CFG spiral drill pipe model range: 300mm 400mm 500mm 600mm 800mm, the center pipe: seamless alloy tube without bending, deformation, not ... to customer requirements. Kelly: overall good verticality, convenient disassembly, installation. 800mm CFG spiral drill pipe