Radioisotopic tube wall thickness gauge

Journal Article · Tue Dec 31 23:00:00 EST 1974 · Sov. J. Nondestr. Test. (Engl. Transl.); (United States)

OSTI ID:7273111

Chizh, V A; Drabkin, L A; Tokarskii, V F

For measuring the wall thickness of thick-walled hot-rolled and centrifugal-cast pipes the VNITI (All-Union Scientific-Research Institute of Pipes) developed a device incorporating a radioisotopic thickness gauge. This semi-automatic machine detects deviations of +-10 to 20% from nominal dimensions along the whole pipe length. The device can be divided arbitrarily into two parts: the measuring instrument proper and the pipe feed machanism. The principle of operation of the device is based on a direct exposure of the pipe to ..gamma..-quanta radiation. The radiation source is placed into a special container outside the pipe, and the detector is placed inside the pipe on a long rod. Isotope /sup 137/Cs is used as the source of radiation with an exposure dose energy, at a distance of 1 m, of 4.9 . 10/sup -4/ R/sec (radioactivity 2 g-eq . Ra). The radiation beam, weakened during the passage through the pipe wall, reaches the detector which has a scintillation counter with a NaI(Tl) crystal and a FEU-14B photoamplifier. The scintillation counter converts the radiation energy into a proportional electric signal which is compared with a constant master voltage in the measuring circuit of the instrument. The size and direction of the unbalance signal provides an indication of the magnitude and direction of the deviation of pipe wall dimensions from the nominal values, and this is indicated by a pointer instrument calibrated in units of this deviation. Provision is made for recording the signal on a diagram tape. (WHK)

• Research Organization: All-Union Scientific-Research Inst. of Pipes, Moscow
• OSTI ID: 7273111
• Journal Information: Sov. J. Nondestr. Test. (Engl. Transl.); (United States), Journal Name: Sov. J. Nondestr. Test. (Engl. Transl.); (United States) Vol. 11:5; ISSN SJNTA
• Country of Publication: United States
• Language: English

Related Subjects

440105* -- Radiation Instrumentation-- Radiometric Instruments-- (-1987)
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ALKALI METAL ISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CESIUM 137
CESIUM ISOTOPES
DESIGN
DIMENSIONS
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
GAMMA SOURCES
IONIZING RADIATIONS
ISOTOPES
MEASURING INSTRUMENTS
NUCLEI
ODD-EVEN NUCLEI
PIPES
RADIATION SOURCES
RADIATIONS
RADIOISOTOPES
RADIOMETRIC GAGES
THICKNESS
THICKNESS GAGES
YEARS LIVING RADIOISOTOPES