EP 0886759 A4 20001122 - COMPTON BACKSCATTER PIPE WALL THICKNESS GAUGE EMPLOYING FOCUSING COLLIMATOR AND ANNULAR DETECTOR
Title (en)
COMPTON BACKSCATTER PIPE WALL THICKNESS GAUGE EMPLOYING FOCUSING COLLIMATOR AND ANNULAR DETECTOR
Title (de)
COMPTON-RÜCKSTREUUNGS-WANDDICKENMESSER MIT FOKUSSIERKOLLIMATOR UND RINGFÖRMIGEM DETEKTOR
Title (fr)
JAUGE D'EPAISSEUR DE PAROI DE TUYAU A RETRODIFFUSION COMPTON EMPLOYANT UN COLLIMATEUR A CONCENTRATION ET UN DETECTEUR ANNULAIRE
Publication
Application
Priority
- US 9703516 W 19970303
- US 1275596 P 19960304
Abstract (en)
[origin: WO9733141A1] This invention is directed toward the measure of the thickness of material using nuclear techniques. More particularly, the invention is directed toward apparatus and methods for measuring the thickness of pipe wall, from the outside of the pipe (70), using an annular detector (50), concentric conical detector collimation (26), and backscatter gamma radiation. A source of gamma radiation (14), preferably at energy 279 keV from mercury-203, is collimated into a pencil beam and impinged perpendicularly upon the outside of the pipe wall to be measured. Compton backscatter radiation from the pipe wall is then measured with an annular, concentric photon detector which preferably comprises a scintillation crystal, such as sodium iodide, optically coupled to a single photomultiplier tube. Pipe thickness is determined from detector response using a predetermined relationship obtained during system calibration. Conical, concentric detector collimation is used to obtain accurate and precise measurements when the pipe is filled with liquid.
IPC 1-7
IPC 8 full level
G01B 15/02 (2006.01)
CPC (source: EP)
G01B 15/02 (2013.01); G21K 1/025 (2013.01)
Citation (search report)
- [XY] US 5400380 A 19950321 - GIGNOUX DOMINQUE [US], et al
- [Y] US 4825454 A 19890425 - ANNIS MARTIN [US], et al
- [Y] US 5195117 A 19930316 - ONG POEN S [US]
- See references of WO 9733141A1
Designated contracting state (EPC)
BE DE ES FR GB IT NL SE
DOCDB simple family (publication)
WO 9733141 A1 19970912; AU 2070397 A 19970922; CA 2248145 A1 19970912; EP 0886759 A1 19981230; EP 0886759 A4 20001122
DOCDB simple family (application)
US 9703516 W 19970303; AU 2070397 A 19970303; CA 2248145 A 19970303; EP 97908911 A 19970303