A method for measuring scale deposits in boiler tubes

Abstract

The invention discloses a measurement method for the depositing amount of oxide skin inside a boiler pipe. A transmitting probe and a receiving probe are installed on the outer wall of the portion, to be measured, of the boiler pipe; the arc length L1 between the peak, in the vertical direction, of the outer arc surface of the boiler pipe and a first acoustic beam transmitting array element is measured; if the serial number of an acoustic beam transmitting array element corresponding to a first ultrasonic wave received by the receiving probe is N, the arc length L3 between the first acoustic beam transmitting array element of the transmitting probe and the acoustic beam transmitting array element of the first ultrasonic wave received by the receiving probe is calculated; according to the arc length L1 between the peak, in the vertical direction, of the outer arc surface of the boiler pipe and the first acoustic beam transmitting array element and the arc length L3 between the first acoustic beam transmitting array element of the transmitting probe and the acoustic beam transmitting array element of the first ultrasonic wave received by the receiving probe, the depositing amount of the oxide skin inside the boiler pipe is calculated. The method is convenient to operate, the on-site detection efficiency of the depositing amount of the oxide skin inside the boiler pipe is improved, and a safety guarantee is provided for normal operation of a power plant boiler.

Description

【Technical field】 [0001] The invention belongs to the technical field of non-destructive testing, and in particular relates to a method for measuring the scale deposition amount in boiler tubes. 【Background technique】 [0002] Thermal power plant units operate in a high-temperature environment for a long time. Since the high-temperature boiler tubes are under high pressure and the operating temperature is within the creep temperature range, after the boiler tubes are put into use, the inner wall of the boiler tubes will be rapidly oxidized in the superheated steam mixture environment. . At the same time, under the conditions of ultra-high temperature, large temperature fluctuations or large pressure fluctuations, the oxidation of the inner wall of the boiler tube will form a multi-layer film. This multi-layer film greatly accelerates the oxidation rate on the one hand, and blocks The heat exchange between the medium in the tube and the tube wall leads to a further increase ...

AI Technical Summary

Problems solved by technology

[0011] The above detection method can prevent the tube explosion accident caused by the peeling and blockage of the oxide scale to a certain extent by judging the peeling of the scale on the inner wall of the boiler tube, but it cannot accurately determine the amount of scale deposited in the U-shaped tube after peeling off, and cannot Accurately predict boiler tube life

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