The present invention provides a material for built up edge formation having a resin block containing a high molecular weight compound having a weight average molecular weight of 510.sup.4 or higher and 110.sup.6 or lower, a medium molecular weight compound having a weight average molecular weight of 110.sup.3 or higher and lower than 510.sup.4, and a carbon.

The present invention provides an entry sheet for drilling which provides higher hole position accuracy than that of a conventional entry sheet for drilling. The present invention provides an entry sheet for drilling, including a metal foil, and a layer including a resin composition and formed on at least one surface of the metal foil, wherein the resin composition includes a resin and tungsten disulfide as a solid lubricant, and the content of the tungsten disulfide included in the resin composition is 10 parts by mass to 200 parts by mass based on 100 parts by mass of the resin included in the resin composition.

The present invention provides an entry sheet for drilling which provides higher hole position accuracy than that of a conventional entry sheet for drilling. The present invention provides an entry sheet for drilling, including a metal foil, and a layer including a resin composition and formed on at least one surface of the metal foil, wherein the resin composition includes a resin and tungsten disulfide as a solid lubricant, and the content of the tungsten disulfide included in the resin composition is 10 parts by mass to 200 parts by mass based on 100 parts by mass of the resin included in the resin composition.

A drilling apparatus has a work robot mounting a drilling blade and moving inside a main pipe and a photodetector for detecting the contour of an opening image formed on the inner surface of a pipe lining material by illumination light. The opening image is scanned, and a two-dimensional image corresponding to the opening image is generated based on the contour points P0 to P8 detected by the photodetector for display on a display unit. The amount of positional deviation between the center of the two-dimensional image on the display unit and the axial center C of the rotary shaft of the drilling blade is calculated, and the pipe lining material is drilled by moving the drilling blade by the amount of positional deviation in a direction in which the positional deviation is eliminated.

A drilling apparatus has a work robot mounting a drilling blade and moving inside a main pipe and a photodetector for detecting the contour of an opening image formed on the inner surface of a pipe lining material by illumination light. The opening image is scanned, and a two-dimensional image corresponding to the opening image is generated based on the contour points P0 to P8 detected by the photodetector for display on a display unit. The amount of positional deviation between the center of the two-dimensional image on the display unit and the axial center C of the rotary shaft of the drilling blade is calculated, and the pipe lining material is drilled by moving the drilling blade by the amount of positional deviation in a direction in which the positional deviation is eliminated.

A drilling apparatus includes a hydraulic motor 27 for rotating a drilling blade 30 that drills a pipe lining material 13, laser light sources 40, 41 for emitting laser beams toward the pipe lining material parallel to the rotary shaft of the drilling blade from positions near the drilling blade to form laser spots on the inner circumferential surface of the pipe lining material, an electric motor 28 for rotating the laser light sources coaxially with the rotary shaft of the drilling blade, and a camera 50 for photographing the trajectory of the laser spots rotating on the inner circumferential surface of the pipe lining material and a bright area that is formed on the inner circumferential surface of the pipe lining material by illumination light from the lateral pipe side. The positioning of the drilling blade is performed so that the trajectory image and the bright area image match.

A drilling apparatus includes a hydraulic motor 27 for rotating a drilling blade 30 that drills a pipe lining material 13, laser light sources 40, 41 for emitting laser beams toward the pipe lining material parallel to the rotary shaft of the drilling blade from positions near the drilling blade to form laser spots on the inner circumferential surface of the pipe lining material, an electric motor 28 for rotating the laser light sources coaxially with the rotary shaft of the drilling blade, and a camera 50 for photographing the trajectory of the laser spots rotating on the inner circumferential surface of the pipe lining material and a bright area that is formed on the inner circumferential surface of the pipe lining material by illumination light from the lateral pipe side. The positioning of the drilling blade is performed so that the trajectory image and the bright area image match.

A boring machine for boring a part of a fluid pipe in an uninterrupted flow state, includes: a shaft member having a leading end to which a cutter is attached; a drive mechanism configured to rotate the cutter and the shaft member around the shaft of the shaft member; and a forward and backward moving operation mechanism configured to move the cutter and the shaft member forward and backward in the axial direction of the shaft member by a handle that is manually rotated. The forward and backward moving operation mechanism is further configured to switch a feed amount of the cutter and the shaft member in the axial direction between at least two different feed amounts according to a rotational amount of the handle.

A boring machine for boring a part of a fluid pipe in an uninterrupted flow state, includes: a shaft member having a leading end to which a cutter is attached; a drive mechanism configured to rotate the cutter and the shaft member around the shaft of the shaft member; and a forward and backward moving operation mechanism configured to move the cutter and the shaft member forward and backward in the axial direction of the shaft member by a handle that is manually rotated. The forward and backward moving operation mechanism is further configured to switch a feed amount of the cutter and the shaft member in the axial direction between at least two different feed amounts according to a rotational amount of the handle.

Entry sheet for drilling including a metallic foil and a layer of a resin composition, the layer formed on the metallic foil without interposing an adhesion layer, in which the layer of the resin composition has a peak attributable to a carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 and a peak attributable to a carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 in infrared spectroscopy, and when the absorbance at the peak attributable to the carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 is represented by Abs(CO)L, and the absorbance at the peak of the carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 is represented by Abs(CO)L, the layer of the resin composition has an absorbance ratio (C) of 0.12 to 1.80, the absorbance ratio (C) represented by the following expression (1).
Absorbance ratio(C)=Abs(CO)L/Abs(CO)L Expression (1).