Acid medium transmission pipeline welded joint and parent metal corrosion simulation testing device and method

Abstract

The invention provides a large-scale multifunctional corrosion stimulation test rack taking a test circular road as a main part, which is used for simulating the corrosion condition of high acid natural gas containing H2S, CO2 and Cl on a pipeline parent metal and a welded joint under the pipeline transmission condition. The device and the method provided by the invention can be applied to pipeline parent bodies with different pipe diameters, materials, steel grades and wall thicknesses, or a welded joint corrosion test; and test functions such as test on corrosion of the pipe section parent metal and the welded joint, sulfide stress cracking (SSC), hydrogen induced cracking (HIC), washout, corrosion inhibitor effect, welding process evaluation, corrosion monitoring method comparison, pipeline-corrosion-preventing process optimization and the like are integrated into a whole; and the test functions, such as preference of the corrosion process in the pipeline are integrated into a whole, thus reasonable material selection and safe welding quality are guaranteed, and the corrosion condition of the corresponding corrosion condition on the welded joint and the parent metal is known.

Description

[0001] technical field [0002] The invention relates to a dynamic corrosion simulation test device and method mainly based on a test ring, which is used for simulating acidic medium H in high-acid natural gas under pipeline transportation conditions. 2 S, CO 2 and Cl - Corrosion status of pipe base metal and weld under single or combined action. [0003] Background technique [0004] In recent years, with the continuous development of gas field exploration and development, among the newly developed gas fields in my country, gas fields with abnormally high temperature, high pressure, and extremely high content of hydrogen sulfide and carbon dioxide have appeared, and the working conditions and medium conditions vary greatly. Medium corrosion conditions are very harsh, Cl - Content up to 1.0×10 5 mg / L, and CO 2 、H 2 S, Cl - Mixed gas fields. h 2 S, CO 2 It has stress corrosion cracking and electrochemical corrosion effects on steel, and is the main factor causing in...

AI Technical Summary

Problems solved by technology

However, the shortcoming of this device is that the range of applicable working conditions is narrow; the gas composition cannot be adjusted, and the test object is single; It is a flat hanging piece, which is quite different from the actual pipeline transportation conditions

[0015] (1) The processing capacity of the device is far less than the actual processing capacity on site, the test loop is short, the pipe diameter is small, and most of them are small indoor test devices, and the obtained test data is difficult to match the actual project;

[0016] (2) The coupon corrosion test is mainly used, with simple design and single function. When testing multiple materials or multiple corrosion methods, it needs to go through multiple tests or use multiple sets of equipment, which increases manpower, material resources and financial resources;

[0017] (3) Most of the test objects are liquid media, and few are suitable for gas media. In contrast, the circulation of gas in the ring is more complicated

Images