Patent ID: 7587842

Claim:
A method of using a ripper tool on a hydraulic arm of a carrier or excavator extendable to a given vertical reach to take down a large storage tank structure having a vertical wall extending around a periphery of the tank and standing at a vertical height above the ground substantially within the given vertical reach of the hydraulic arm and made of a heavy, durable material such as metal for demolition, comprising: (a) providing the ripper tool with a ripper blade having a blade portion with a sharp inner edge extending along a concave curved arc to a sharp point, wherein the sharp point at the end of the blade portion provides a point of attack for punching a hole into tank walls, and the concave, sharp inner edge provides a shearing force for cutting through tank walls; (b) positioning the ripper tool on an end of the hydraulic arm and extending the hydraulic arm to its given vertical reach on the excavator and operating the hydraulic arm so that it is pulled downward so as to keep the ripper blade positioned on a vertical cut made from a top part of the vertical height of the tank wall down to a lower part of the tank wall, (c) cutting a series of long vertical cuts into the tank wall with the ripper tool down the vertical height of the tank wall from its top part to its lower part in swathes at spaced intervals around a substantial part of the periphery of the tank structure on at least one side thereof in order to weaken the at least one side of the tank structure, (d) collapsing the at least one side of the tank structure weakened by the series of vertical cuts around the periphery of the tank wall on said one side for bringing down the top part of the tank structure down to the ground on said one side, and (e) ripping the remainder of the tank structure into smaller pieces for demolition from said one side brought down to the ground.