METAL TOUCH PORTION DETECTING METHOD FOR BURIED METAL TUBE

Japanese Patent JP2005134159

A

To provide a method for locating a metal touch portion when a buried metal tube is in metal-touch with another metal tube buried in parallel therewith.

This method is for detecting the metal touch portion of the buried metal tube with an anticorrosive coating with the other metal tube close-buried in parallel therewith. AC signals of different frequencies are applied to the buried metal tube and to the ground from both the sides of an objective zone of detection. The intensity of a magnetic field is measured by moving magnetometric sensors disposed on a ground surface to each of measurement points placed at prescribed intervals in the extension direction of the buried metal tube while scanning in the orthogonal direction. By signal-processing obtained data, changes in the intensity of the magnetic field are compared with each other at respective measurement points corresponding to the signals of different frequencies, thereby determining whether there is a metal touch portion, and its location.

WO/2002/097424	PIPE MATERIAL DISCRIMINATION
JPS6017350	METHOD FOR MEASURING TRANSFORMATION RATE OF METAL
WO/2021/081103	ELECTRONICALLY-CONTROLLED DIGITAL FERROFLUIDIC DEVICE AND METHOD FOR SCALABLE AND ADDRESSABLE BIOANALYTICAL OPERATIONS

KOGA RYUJI
SASAKI NOBUHIRO
KAWAKAMI MAKOTO

JP2003367897A

May 26, 2005

October 28, 2003

Click for automatic bibliography generation  

NIPPON STEEL CORP

G01N27/72; F16L1/024; (IPC1-7): G01N27/72; F16L1/024

JPS6281557A	1987-04-15
JP2000249685A	2000-09-14
JPS64481A	1989-01-05
JPS6378063A	1988-04-08
JPH10206390A	1998-08-07
JP2001215204A	2001-08-10

Nobuyuki Hayashi
Takehiko Katayose

Previous Patent: DEFECT DETECTOR

Next Patent: CORROSION SENSOR, METHOD FOR MEASURING CORROSIVE ENVIRONMENT OF OVERLAP STRUCTURE PART, METHOD FOR D...