A method is disclosed for surveying drill holes with a drilling arrangement and borehole survey assembly. The method can include providing a drill tool having at least one drill rod and a drill bit assembly, and providing a borehole survey tool having a sensor) for measuring a borehole. In the method a drill tool having a central flushing channel for conducting flushing fluid to the drill bit assembly is used, and the borehole survey tool is arranged in the central flushing channel so that flushing fluid can flow in the central flushing channel past the borehole survey tool.

An impact-driven tool includes a cylinder and a piston slidably inserted into the cylinder and has a large-diameter portion. The cylinder includes: a chamber on one end side; a chamber on the other end side; a communication path that allows the chamber on one end side and the chamber on the other end side to communicate with each other; and a valve chamber that is continuous with one end side in the axial direction of the communication path, and a valve body for piston lifting control that is incorporated so as to be movable up and down and is provided in the valve chamber.

An impact-driven tool includes a cylinder and a piston slidably inserted into the cylinder and has a large-diameter portion. The cylinder includes: a chamber on one end side; a chamber on the other end side; a communication path that allows the chamber on one end side and the chamber on the other end side to communicate with each other; and a valve chamber that is continuous with one end side in the axial direction of the communication path, and a valve body for piston lifting control that is incorporated so as to be movable up and down and is provided in the valve chamber.

Provided is an undersea mining base capable of corresponding with slopes and undulations of seabed ore deposits. The undersea mining base includes a seabed mineral mining device configured to form a pit in a seabed ore deposit and a platform equipped with the seabed mineral mining device and capable of self-traveling in at least one of an X direction and a Y direction.

A method for estimating wear of a drill bit in percussive rock drilling. A percussion device is configured for generating shock waves in a drill bit for breaking rock. The method includes, during drilling determining a percussion frequency of the percussion device; and estimating wear of the drill bit based on the determined percussion frequency of the percussion device and a model representation of the wear of the drill bit as a function of percussion frequency, wherein the model representation is configured to output the estimated wear of the drill bit utilizing the determined percussion frequency as input signal.

A rock drill includes a frame, a percussion member, an axial shank, and an axial sleeve provided within the frame and including a first pressure surface provided in a first pressure space and a second pressure surface provided in a second pressure space. A first channel is provided in the axial sleeve for providing a connection between the first pressure space and the second pressure space in at least one position of the axial sleeve in the frame. A second pressure channel connected to the second pressure space is connectable to external pressure. A pressure accumulator is connected to the first pressure space and the flow of the pressure medium outwards from the first pressure space is throttled.

A method and a mandrel for forming a cavity at a target location. The mandrel may include a main drilling shaft, a plurality of T-shaped elements, a hollow-cylindrical-shaped element, and a plurality of parallelepiped-shaped stiffener plates. The main drilling shaft may include a hammer insertion part positioned at a first end of the main drilling shaft, a bore head positioned at a second end of the main drilling shaft, and a medium part positioned between the hammer insertion part and the bore head. The plurality of T-shaped elements may be mounted adjacently around the medium part in a way such that forming a closed octagonal from a top-view of the mandrel. A first size of a first cross-section at a first location from a top-view of the plurality of T-shaped elements around the medium part may be larger than a second size of a second cross-section at a second location from the top-view.

A measurement tool for use in pneumatic percussion drilling comprises a body comprising one or more measuring instruments positioned in a drill string above a pneumatically operated hammer of the drill string.

The drilling machine comprises a control unit and at least one sensor. The drilling machine further comprises a percussive element and a tool, wherein an end of the tool comprises a drill bit configured to strike rock. The percussive element is configured to impact the tool and the tool is configured to transfer impulse energy generated by the percussive element to the drill bit. The method during drilling comprises collecting data depending on force fed into the rock and indentation depth into the rock at an impact of the percussive element. The method further comprises determining a percussion procedure based on the collected data, and determining a deviation between the percussion procedure and a reference percussion procedure. The method further comprises adjusting one or more drilling parameters related to the drilling process based on the deviation.

The drilling machine comprises a control unit and at least one sensor. The drilling machine further comprises a percussive element and a tool, wherein an end of the tool comprises a drill bit configured to strike rock. The percussive element is configured to impact the tool and the tool is configured to transfer impulse energy generated by the percussive element to the drill bit. The method during drilling comprises collecting data depending on force fed into the rock and indentation depth into the rock at an impact of the percussive element. The method further comprises determining a percussion procedure based on the collected data, and determining a deviation between the percussion procedure and a reference percussion procedure. The method further comprises adjusting one or more drilling parameters related to the drilling process based on the deviation.