Ultra-supercritical coal-fired power generator pipeline weld joint online creep monitoring method

Abstract

The invention discloses an ultra-supercritical coal-fired power generator pipeline weld joint online creep monitoring method. According to the method,a pipeline weld joint measuring tool is configured, the pipeline weld joint measuring tool comprises a tool A, a tool B, a probe, a spring loading device, an access signal acquisition and transmission device and a weld joint. The monitoring method comprises the following steps of: the tool A and the tool B are respectively arranged on two sides of the weld joint; and the probe is fixedly connected to the tool B. In order to avoid the situation that due to the fact that the service temperature of a pipeline is high, the weld joint can be subjected to thermal expansion, and the steps cannot be further operated. According to the method disclosed by the invention, the online measurement of the creep of the weld joint is successfully implemented for the first time, and a measurement result is closer to an actual situation; the limitation of pipe cutting is small; capacitance impedance measurement and high-temperature metal creep expansion measurement are combined for the first time, the three-stage mechanism of metal creep failure and weld joint creep deformation online detection are fused; and tracking monitoring and early warning of metal weld joint creep deformation are achieved.

Description

technical field [0001] The invention relates to the technical field of detection, in particular to an online creep monitoring method for pipeline welds of ultra-supercritical coal-fired generators. Background technique [0002] As we all know, the development of the contemporary economy is inseparable from the supply of energy. The ultra-supercritical coal-fired generating units have a relatively large amount in the country, and they are responsible for the country’s economic development. , a large number of high-alloy heat-resistant steels such as SA335-P92 and 122 are used as steam pipelines. The general service temperature of such pipelines is above 590°C, which exceeds the upper limit of the temperature for creep damage of materials. Due to normal service When the service life is approaching or the service life is approaching due to special working conditions, the probability of creep damage failure will increase significantly, especially the weld seam of the pipeline as...

AI Technical Summary

Problems solved by technology

Creep damage detection is an important detection method for the safe service of pipelines. At present, the detection and supervision is mainly carried out by using the creep ruler to detect and record manually when the unit is shut down. However, this detection method is extremely complicated and the surface of the detected part is easy to be flat Temperature, ambient temperature, etc., and the detection accuracy is only 0.02mm, so the timeliness of early warning is poor, and online monitoring cannot be realized. Due to the low accuracy of detection data, the latest "Metal Technical Supervision Regulations for Thermal Power Plants" (DL / T 438-2016) has canceled the supervision and testing requirements, but it does not mean that the testing is worthless

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