Abstract: The object of the invention is to measure, surely and in a stable condition, the orientation of a pig body in the pipe of a pipeline thereby to correct errors caused by measuring the linear shape of the pipeline by means of a gyroscope sensor. A three-axis gyroscope sensor unit 4 is placed in a pig body 2 such that one of measuring axes of the gyroscope sensor unit 4 is parallel to the center axis of the pig body 2 and is fixed so as to prevent the gyroscope sensor unit 4 from being shifted in position with respect to the pig body 2. Two sets of six distance measuring means 5-10 and 11-16 are arranged on the outer periphery of the pig body 2 at two positions in the back and forth direction (in a direction of travel), respectively, and the six distance measuring means of each set are arranged at equal intervals in the circumferential direction of the pig body 2.

Abstract: An inner burr cutting and inner surface cleaning apparatus comprises a base, a carriage mounted on the base and reciprocable along a long pressure-welded pipe of medium and small diameters, a supporting tube supported at one end thereof by the carriage and insertable into the pipe having an inner burr produced on an inner surface thereof, a first motor mounted on the carriage, a rotary shaft coaxially inserted into the supporting tube, having one end protruding from the other end of the supporting tube and rotated at the other end by the first motor, an inner burr cutting device fixedly mounted on the rotary shaft for cutting off the inner burr, sets of rollers, each set thereof being arranged circumferentially on an outer periphery of the supporting tube for contacting the inner surface of the pipe, a centering device disposed at the other end of the supporting tube for centering the cutting device in the pipe, a second motor mounted on the centering device and having a drive shaft coaxial with the rotary sh

Abstract: An inner burr cutting, inner face cleaning and inner face painting apparatus for long pressure-welded pipes of medium and small diameters comprises a carriage mounted on a base for reciprocal movement, a supporting tube mounted on the carriage to be inserted into a long pressure-welded pipe of a small or medium diameter, a hollow rotary shaft projecting from the supporting tube, an inner burr cutting device fixed to the rotary shaft, a mechanism for centering the inner burr cutting device in the pressure-welded pipe, a spatter crushing brush, an electromagnet device for attracting spatters and inner burr chips, a spattering prevention device, a paint spraying device disposed ahead of the electromagnet device, and a cooling device surrounding the pressure-welded pipe.