Abstract: 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.

Abstract: 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.

Abstract: A drill rod suitable for a hydraulic drilling apparatus, at the drilling end (I) of which there is a drilling device (1), that includes at least drilling equipment (2) and hammering equipment (5) as well as preferably flushing equipment (10) also, to drill a hole by use of the drilling equipment (2) by a feeding motion along the longitudinal axis (s) of the drilling device (1) and by a rotational motion (w) around the longitudinal axis (s) as well as by a to-and-from or a like hammering motion (t). The drilling device (1) has jointing equipment (3) for fastening of a drill rod (4) preferably in a removable way to increase the drilling depth of the drilling apparatus.

Abstract: A method of using an organic, oil-based pressurized medium derived from natural biological metabolism for the percussion device in a drilling device of a drilling apparatus having a drilling bit at its one end for drilling a hole in the ground comprises: a) causing the organic oil-based pressurized medium derived from natural biological metabolism to flow in the drilling hole through at least the drilling device and possibly one or several drill rods, when joined to the drilling device for increasing the drilling depth of the drilling device, b) driving the percussion device for generating the percussion movement by the organic oil-based pressurized medium derived from natural biological metabolism supplied through a first flow channel provided in the drilling device and the drill rod, c) removing drilling waste generated by the drilling bit at the end of the drilling device by a scavenging agent supplied through a second flow channel provided in connection with the drilling device and the drill rod, and d) s