A cutting head includes a main body that is attachable to an ice drill shaft at a top side. The main body includes a bottom side that has a bottom peripheral surface. The cutting head includes at least one cutting edge that is disposed on the main body. The cutting edge is configured to perform a cutting operation at the bottom side of the main body. The cutting head includes a cutting rate control pad that is disposed on the bottom side of the main body. The cutting rate control pad extends away from the bottom peripheral surface.

A self propelling vehicle capable of propagating through a solid medium, comprising two or more rotors, arranged in tandem, and means for rotating the rotors, each rotor being formed as a hollow rotational body with an external helicoidal flighting, configured to engage surrounding solid medium, wherein the flightings of any pair of adjacent rotors follow helicoids of mutually opposite senses and the means for rotating are operative to rotate the adjacent rotors in mutually opposite senses.

A self propelling vehicle capable of propagating through a solid medium, comprising two or more rotors, arranged in tandem, and means for rotating the rotors, each rotor being formed as a hollow rotational body with an external helicoidal flighting, configured to engage surrounding solid medium, wherein the flightings of any pair of adjacent rotors follow helicoids of mutually opposite senses and the means for rotating are operative to rotate the adjacent rotors in mutually opposite senses.

A frost removal system is for thawing frozen ground and a method removes frost from a selected area of frozen ground. The method can include providing at least one heat transfer device; auguring a hole into the frozen ground to at least a depth of the frost.

The at least one heat transfer device is lowered into the selected area of frozen ground and self-augured to the predetermined depth. The at least one heat transfer device is heated and the heat is allowed to travel along a length of the at least one heat transfer device. Heat is applied from the at least one heat transfer device for thawing the selected area of frozen ground until the frost is removed. The removal system may also be used to remove moisture from saturated soil and to bake columns of soil with increased load-bearing capacity.

A frost removal system is for thawing frozen ground and a method removes frost from a selected area of frozen ground. The method can include providing at least one heat transfer device; auguring a hole into the frozen ground to at least a depth of the frost.

The at least one heat transfer device is lowered into the selected area of frozen ground and self-augured to the predetermined depth. The at least one heat transfer device is heated and the heat is allowed to travel along a length of the at least one heat transfer device. Heat is applied from the at least one heat transfer device for thawing the selected area of frozen ground until the frost is removed. The removal system may also be used to remove moisture from saturated soil and to bake columns of soil with increased load-bearing capacity.

A shrouded screw apparatus includes an outer tube, a telescoping inner tube, an auger bit, and an anti-rotation pin. The outer tube has a first sidewall defining a first interior chamber. The first sidewall has an opening defined therethrough. The inner tube is positioned in the first interior chamber. The inner tube has a second sidewall defining a second interior chamber. The second sidewall has a longitudinal groove defined therein. The inner tube is configured to extend from and retract within the first interior chamber of the outer tube. The auger bit is positioned in the second interior chamber and is rotatably coupled to the inner tube. The anti-rotation pin is coupled to the first sidewall of the outer tube and extends inwardly into the first interior chamber. The pin engages the longitudinal groove of the inner tube.

A shrouded screw apparatus includes an outer tube, a telescoping inner tube, an auger bit, and an anti-rotation pin. The outer tube has a first sidewall defining a first interior chamber. The first sidewall has an opening defined therethrough. The inner tube is positioned in the first interior chamber. The inner tube has a second sidewall defining a second interior chamber. The second sidewall has a longitudinal groove defined therein. The inner tube is configured to extend from and retract within the first interior chamber of the outer tube. The auger bit is positioned in the second interior chamber and is rotatably coupled to the inner tube. The anti-rotation pin is coupled to the first sidewall of the outer tube and extends inwardly into the first interior chamber. The pin engages the longitudinal groove of the inner tube.

A steering head for use with a casing, the steering head having a body with a first body end with a lead edge, a second body end with a rear edge, and a body surface extending from the lead edge to the rear edge, an outer tube with an internal side generally facing the body surface, the outer tube extending from the first body end to the second body end, and a steering flap disposed on an external side of the outer tube having a first flap face facing radially inwardly and a second flap face facing radially outwardly. A fluid dispenser is disposed in a void defined between the outer tube and the body.

A steering head for use with a casing, the steering head having a body with a first body end with a lead edge, a second body end with a rear edge, and a body surface extending from the lead edge to the rear edge, an outer tube with an internal side generally facing the body surface, the outer tube extending from the first body end to the second body end, and a steering flap disposed on an external side of the outer tube having a first flap face facing radially inwardly and a second flap face facing radially outwardly. A fluid dispenser is disposed in a void defined between the outer tube and the body.

A pile-forming method for a compound extruded and expanded pile, comprising using a compound extrusion and expansion drilling tool of pile-forming equipment for a compound extruded and expanded pile to drill, extrude, and expand to form a bore, wherein when upwardly rotating and lifting, expansion bodies of the compound extrusion and expansion drilling tool enlarge, and at the same time, a concrete pump is started up to pour a pile material under pressure into the pore for the pile, to reach a pile top mark height, obtaining a compound extruded and expanded pile. Pile-forming equipment for a compound extruded and expanded pile is also disclosed, comprising a compound extrusion and expansion drilling tool and a control system thereof. The compound extrusion and expansion drilling tool comprises a drill stem. A plurality of expansion bodies are provided on a threaded section of a drill bit of the drill stem.