8 results about "Flow-accelerated corrosion" patented technology

The invention belongs to the technical field of ocean engineering, and discloses a seabed vibration elbow solid-liquid two-phase flow erosion corrosion coupling analysis method and system. The method comprises the following steps: establishing a three-dimensional fine model of a local bent pipe section; constructing a flow accelerated corrosion model by using a mass transfer equation and a solubility equation to calculate a flow accelerated corrosion rate; an E / CRC particle erosive wear model is introduced to calculate the erosive wear rate of particles to the wall surface of the pipeline; an erosion-corrosion coupling model is constructed based on the electrochemical corrosion secondary current model to simulate the erosion corrosion process of solid-liquid two-phase flow in the vibration pipeline, and an erosion corrosion coupling response rule in the vibration elbow is obtained. Compared with an original analysis method which only considers erosion wear, the erosion corrosion rate calculation precision is improved by 36%, the simulation result and experiment comparison error is reduced to be within 20%, and technical support is provided for accurate analysis of pipeline damage under the erosion corrosion coupling effect.

The invention belongs to the technical field of flow accelerated corrosion testing, and particularly discloses a high-temperature water vapor pipeline flow accelerated corrosion performance testing device and method, and the high-temperature water vapor pipeline flow accelerated corrosion performance testing device comprises a detachable testing section, a steam generator, a spraying system and a steam compressor. The steam compressor is connected with the outlet end of the test section and the steam generator and is used for pressurizing to form high-flow-rate steam flow. The spraying system is connected with the bottom of the steam generator, the nozzle is arranged on the pipeline, and liquid drops are introduced into steam flow to form gas-liquid two-phase flow. A DCPD measuring system is integrated in the test section, comprises a sample clamping assembly, an electrode penetrating assembly and a sensor assembly, and is used for clamping a sheet-shaped sample and measuring the corrosion performance. According to the invention, the actual service conditions of the secondary loop pipeline of the nuclear power plant in a high-temperature, high-pressure and gas-liquid two-phase impact environment can be accurately simulated, and meanwhile, the corrosion thinning rate of the material is monitored in real time by utilizing the DCPD measurement system integrated in the detachable test section, so that the hysteresis quality of a traditional offline measurement method is overcome, and the accuracy of experimental data is improved.

The invention relates to a method, a system and equipment for predicting flow accelerated corrosion distribution of a bent pipe. The method comprises the following steps: acquiring elbow pipe information and environment information for a to-be-predicted elbow pipe; establishing a geometric model of the bent pipe to be predicted according to the bent pipe information; according to the environment information, physical fields of the geometric model of the to-be-predicted elbow are simulated, the geometric model provided with physical fields is obtained, and the physical fields comprise a secondary current distribution physical field, a dilute material transfer physical field and a flow field physical field; and calculating the corrosion rate distribution of the bent pipe to be predicted according to the geometric model provided with the physical field. According to the method, the integration of chemical reaction, interface electrochemical reaction and mass transfer process of species is fully considered, the corrosion rate distribution of the bent pipe can be predicted more accurately, and theoretical basis and guidance are provided for accelerated corrosion and protection of pipeline flow.

The application discloses a kind of air cooling island flow accelerated corrosion simulation test system and method, main loop subsystem, including high-purity water tank, main loop outlet pipe, electrode flow cell and main loop return pipe;The water outlet of high-purity water tank is connected with the one end of main loop outlet pipe, the other end of main loop outlet pipe is connected with the water inlet of electrode flow cell, the one end of main loop return pipe is connected with the water outlet of electrode flow cell, the other end of main loop return pipe is connected with the backwater of high-purity water tank;Dosing subsystem is used to add alkali agent or oxidizing agent to main loop outlet pipe;Flow accelerated corrosion test subsystem includes test electrode and corrosion tester;Test electrode is placed in electrode flow cell, and test electrode is connected with the input end of corrosion tester by wire;The material of test electrode is the same as the material of the equipment to be simulated air cooling island;The application realizes the real simulation of air cooling island equipment, meets the simulation of high flow rate and anaerobic condition, and the error of simulation test result is small.

The invention discloses a low-alloy corrosion-resistant welding wire and a welding method, and relates to the technical field of welding. The low-alloy corrosion-resistant welding wire comprises the following chemical components: 0.03%-0.10% of C, 0.2%-0.3% of Si, 0.8%-2.4% of Mn, 0%-1.5% of Ni, 0.4%-1.5% of Cr, less than or equal to 0.005% of S, less than or equal to 0.005% of P, less than or equal to 0.02% of Als and Fe. The components of the welding wire do not comprise alloy elements such as Cu, Mo and Ti, a proper amount of Cr and Ni are added, and the compactness of a welding line rust layer, especially the compactness of an inner rust layer can be remarkably improved by adding Cr into the welding wire, so that the welding wire has excellent corrosion resistance; and by adding a proper amount of Ni element, grains can be refined, so that the structure is more easily converted into acicular ferrite, and the toughness of a welding seam is improved. By the adoption of the welding wire, the impact toughness of obtained weld metal reaches 80% or above of that of low-alloy corrosion-resisting steel, under the flowing accelerated corrosion condition, the corrosion step of the weld and a heat affected zone / base metal is smaller than 30 microns, the flowing medium corrosion resistance and impact resistance of a steel pipe are remarkably improved, and application and popularization of the low-alloy corrosion-resisting steel in a heat supply pipe network are promoted.

The invention belongs to the field of flow accelerated corrosion testing of nuclear power plant secondary circuit pipeline materials, and particularly discloses a device and method for monitoring flow accelerated corrosion thinning through a radioactive tracer method.The device comprises a test pipe section embedded with 60Co, and the mass fraction of cobalt in the pipe is 0.1%-1.0%; the fluid circulation system is used for forming simulation fluid with preset temperature and pressure and comprises a steam generator, and a turbocharging module, a fluid circulation pump and a spray control unit which are integrated in the steam generator; the gamma-ray monitoring system is provided with a plurality of NaI detectors; the cobalt interception module is used for blocking 60Co recirculation interference and comprises ion exchange resin and a filter; and the downstream pipeline is also connected with an environment detection module and a water chemical regulation system. The problems that in the prior art, the corrosion amount cannot be monitored in real time, and an electrochemical method is poor in reliability are solved, real-time monitoring of the corrosion amount is achieved, the measurement reliability under the conditions of the high flow speed and the gas-liquid two-phase flow is improved, and the activity signal and the actual corrosion amount are accurately correlated.

The invention discloses a drain pipeline anti-corrosion device, a heat supply system and a drain pipeline anti-corrosion method.The drain pipeline anti-corrosion device is characterized in that the data acquisition end of a control unit is connected with the data sending end of an oxygen-enriched water metering pump and used for obtaining a flow signal of the oxygen-enriched water metering pump; the output end of the control unit is connected with the control end of the oxygen-enriched water metering pump; the output end of the control unit is connected with the control end of the oxygen introduction unit; the output end of the oxygen introduction unit is connected with the input end of the oxygen-enriched water preparation unit, the output end of the oxygen-enriched water preparation unit is connected with the first end of the oxygen-enriched water metering pump, and the second end of the oxygen-enriched water metering pump is connected with an inlet of a drain pipe of the heating network heater. According to the drain pipe device, oxygen-enriched water is introduced into the drain pipe of the heating network heater, the oxygen content in the drain pipe is increased, a compact oxidation protection layer can be formed in the drain pipe, electrochemical reaction in the drain pipe is hindered, and flowing accelerated corrosion of the drain pipe is inhibited.

This invention relates to a simulation method and system for accelerated corrosion in a two-loop pipeline. The method includes: constructing a computational domain geometric model of the two-loop pipeline; discretizing the computational domain geometric model into a finite number of grid cells; cyclically updating the grid cell node coordinates and solving the fluid control equations to obtain flow field data step by step until the convergence condition or the total simulation time is reached. The fluid control equations use the incompressible Navier-Stokes equations described by ALE as the core of the control. Simulation results are generated based on the flow field data. By introducing the incompressible Navier-Stokes equations described by ALE as the core of the fluid control equations, the influence of grid movement on fluid flow can be accurately considered during the dynamic change of the computational grid as the wall thins. This avoids the problem of fixed grids failing to capture boundary layer evolution and the element distortion caused by grid reconstruction, significantly improving the accuracy and stability of flow field simulation under dynamic boundary conditions.