Erosion, one of the important reasons for material damage or equipment failure, has become the most common form of gas pipeline damage [
1]. Natural gas pipelines in service always contain a certain amount of solid particles (dust) caused by gas source differences and pipe wall corrosion wear off [
2]. A portion of the solid particles gather at the bottom of the separator and then are discharged through the gas–solid two-phase flow pipeline connected with the separator. With the deepening degree of erosion, the solid particles will eventually lead to pipeline leakage damage, influencing the environment and people’s life [
3]. Actual damaged pipelines are shown in
Figure 1 [
4]. Statistically, gas transmission stations in a given area, over six years, have undergone pipe perforations five times and serious pipe wall thinning three times. However, these pipe perforation events have not been identified in advance and serious pipe wall thinning events have been found occasionally in the process of station renovation. That is, on the one hand, pipe perforation and severe pipe wall thinning are of great safety concern for the gas transmission station operation; on the other hand, there have been no reliable methods to predict the degree of pipeline erosion.
According to the specific mechanism and experiment, experts and scholars at home and abroad in recent years have established different erosion theories and put forward different erosion rate predicting equations that consider various erosion parameters [
3]. From the aspect of erosion theory, Bitter [
5] proposed the theory of deformation wear from the viewpoint of energy balance, but this theory lacked the support of a physical model. Finnie [
6] proposed a micro cutting theory that well explained the law of plastic material erosion under a low impact angle, but this theory was not suitable for brittle material erosion and plastic material erosion under high impact angle. Levy [
7] proposed a theory of extrusion forging that only focused on high-impact-angle erosion. Tilly [
8] studied the impact of plastic material erosion by particles and put forward a secondary erosion theory suited for brittle particles under high impact angle. From the aspect of erosion rate prediction, Oka et al. [
9,
10] put forward an E/CRC erosion wear experience relation equation that considers the target material hardness, particle diameter and particle properties. Lin [
11] presented a relation function for erosion rate, particle size, flow and impact angle. API-14E [
12] proposed an erosion velocity empirical formula that considered mixed fluid density, but the deviation of calculation results was bigger in the prediction of erosion speed under lower fluid mixing density. Desale et al. [
13] put forward a relational expression for the erosion rate and particle size and pointed out that this expression was related to material properties, experimental conditions, particle velocity and particle size distribution. Ou et al. [
14,
15] studied the liquid phase distribution and the particle trajectory in gas-liquid-solid multiphase flow pipeline and then an erosion rate formula was put forward. Lian et al. [
16] put forward a change curve for the erosion rate and angle of the bent sub after performing an erosion simulation for a sand piping bent sub. Gnanavelu et al. [
17] obtained the schematic diagram of stainless steel wall erosion loss for different particle impact angles and the impact speeds by integrating experimental results and computational fluid dynamics simulation. Lester et al. [
18] obtained a fitted formula for the thickness erosion loss including the particle impact velocity and angle through a matching experiment and computational fluid dynamics simulation data of liquid-solid two phase fluid on a cylinder sample. Feng et al. [
19] applied a self-defining function to fix the initial erosion calculation model of computational fluid dynamics software (FLUENT) software, then studied the liquid-solid erosion rule in the sudden expansion and contraction pipe as well. Zhang et al. [
20] predicted the wall erosion process and compared wall thickness erosion loss for bending tubes surface with different angles by simulating liquid-solid two-phase flow in bend tubes. Li et al. [
21] found that the wall thickness erosion loss along with the increase of liquid phase velocity increased exponentially under the working condition of hydraulic fracturing in a restriction choke. Ran [
22] proposed an erosion calculation model suitable for hydraulic jet fracturing conditions according to the rule of erosion damage and sand distribution in a dual-cluster hydraulic ejector.
Although there are many studies on the liquid-solid two-phase flow erosion, nevertheless, research on Gas–Solid two-phase flow erosion is relatively lacking. In addition, because most research on Gas–Solid two-phase flow erosion is limited to the proposed parameter conditions, it is difficult to combine research results with actual working conditions. Therefore, a recognized and widely applicable prediction method for the production field to accurately forecast the erosion level of material is lacking. Consequently, according to the erosion characteristics of pipeline material, it is necessary to establish a maximum erosion rate prediction equation for the Gas–Solid two-phase flow pipe widely used for engineering application in gas transmission stations by simulating the environment closer to actual operation conditions.