Research on the International Competitiveness and Sustainable Trade Development of the Key Equipment and Components of China’s High-Speed Rail

Abstract

The high-speed rail industry (from now on referred to as HSR) in China is flourishing, and improvements in its international competitiveness and the sustainable development of trade are gradually attracting international attention. This study examined data related to trade between major countries producing and importing key HSR equipment and components from 2013 to 2022. The International Competitiveness Index, Trade Complementarity Index, and Trade Integration Index were used to study the international competitiveness of the key equipment and components of China’s HSR, as well as the bilateral trade complementarity between China and other HSR powers. It also studied the degree of bilateral trade integration between China and these HSR powers, as well as that between China and the “Belt and Road” countries. Then, the ARIMA model was established by using Python 3.9.5 software to predict the degree of trade integration between China and the above countries from 2023 to 2027. The results show the following: (1) Some of the key equipment and components of China’s HSR have international competitiveness, but some have shortcomings. (2) China and HSR powers have both trade competition and trade complementarity in the field of key equipment and components. (3) The trade integration of key HSR equipment and components between China and countries along the “Belt and Road” is high. Overall, after ten years of development, China’s HSR industry had improved by 2022. The HSR market in the “Belt and Road” countries is the market that China’s HSR industry must focus on for sustainable development in the future.

1. Introduction

China’s HSR industry is booming, with outstanding technological, construction, and management advantages. It has not only built a huge HSR network at home but has also demonstrated strong competitiveness on the international stage. However, the competitive position of the HSR industry in the international market does not match that of China, a large HSR manufacturing country. This is mainly due to the low overall development level of China’s key HSR equipment and components. It is not difficult to see from the experience of the development of this powerful country in the HSR industry and the focus of international market competition in the HSR industry that the key equipment and components of HSR, as important carriers of new knowledge, are the concrete embodiment of the development level of modern science and technology, and they are also important strategic supports to improve the international market competitiveness of the HSR industry.

However, it is also not difficult to see from the trade status of the key equipment and components of China’s HSR industry that the international competitiveness of China’s HSR industry needs to be improved. According to the calculations of the UN COMTRADE database, the top six countries in terms of import and export trade value of nine types of key equipment and components in HSR (see Section 3.2 for specific details) in 2022 are as follows: Germany, at USD 2.816 billion; the United States, at USD 1.981 billion; Austria, at USD 1.45289 billion; China, at USD 1.45282 billion; Spain, at USD 815 million; and France, at USD 643 million. The value of import and export trade between China and Austria is almost the same, and China ranks fourth. The authors also calculated the total trade volume of key HSR equipment and components between China and the rest of the world from 2013 to 2022. In 2013, it was USD 1.599 billion. In 2015, it rapidly rose to a peak of USD 2.87 billion. In 2017, it rapidly declined to a low of USD 1.283 billion, and then stabilized at USD 1.453 billion in 2022. Although the export data of key equipment and components of China’s HSR industry showed a steady development trend as a whole, the export data of key equipment and components of some subcategories showed a slowing or even downward trend. China’s HSR industry still has some weaknesses in the international competition of its key equipment and components. For example, the international competitiveness of its key equipment and components such as HSR maintenance or service vehicles is weak, and there are still some bottlenecks that need to be addressed [1].

In order to meet its own development needs, China must import a significant amount of key equipment and components from HSR powers annually. Additionally, in an effort to establish a presence in the international market of the HSR industry, China aims to export key equipment and components to HSR powers and countries involved in the “Belt and Road” initiative. The strength of China’s international competitiveness in HSR key equipment and components is a crucial consideration. Identifying the countries with which China can form the best trade complementarity, as well as those with which it should maintain closer trade ties in the future, are pressing issues for sustainable development within China’s HSR industry. These concerns also extend to other countries’ development within the HSR industry. Therefore, this paper utilizes objective analysis methods such as the Revealed Comparative Advantage Index (RCA), the Trade Complementarity Index ($C_{ij}^k$), the Trade Integration Index (TII) and a predictive model (ARIMA) to address these issues.

2. Literature Review

The sustainable international competitiveness, trade complementarity, and trade integration of China’s HSR industry are key issues for this industry to address in order to base itself on the global market. The key core technologies of HSR are the key equipment and components of HSR. The HSR industry drives the development of upstream and downstream industries. Promoting the trade development of the key equipment and components of HSR will not only drive the development of the HSR industry but also drive the development of manufacturing-related fields on a large scale.

Many scholars have carried out research from the perspective of the international competitiveness and sustainable competitiveness of the manufacturing industry. Sun et al. [2], taking the photovoltaic industry as an example, found that core technology competitiveness is an important part of the growth of photovoltaic enterprises, but they also established that enterprises must maintain a dominant position in the industry for a long time and must distinguish between domestic and foreign market demands, so as to achieve the healthy, stable, and sustainable growth of China’s photovoltaic industry. Chen [3] found that even if manufacturers conduct extensive research and development (R&D), they cannot ensure sustainable competitiveness. Guo et al. [4] found that the highest growth rates from 2005 to 2020 were shown by Japan, China, Germany, and the United States, respectively, in terms of the Revealed Comparative Advantage Index (RCA) of the rail, shipbuilding, aerospace, and other transportation equipment manufacturing industries. Yu [5] found that industrialized countries such as the United States, Japan, and Germany attach great importance to the growth of the manufacturing industry, especially the consistency of the advanced manufacturing industry in maintaining its global competitiveness. Yao [6] used the RCA method from the perspective of digital trade to study China’s dominant comparative interests in digital trade. It was found that the RCA of China is lower than that of other countries such as the United Kingdom, the United States, Japan, and India. Li [7], using the RCA, compared the international competitiveness of China and South Korea with regard to resource-intensive, technology-intensive, capital-intensive and labor-intensive products from 2007 to 2021. Ejaz [8] stressed the importance of management strategy and explained how manufacturing enterprises formulate strategies to achieve sustainable competitiveness. Corovic et al. [9] measured the textile and clothing export competitiveness of the western Balkan countries to the EU-28 market, and their results showed that the sustained growth of the market share would significantly improve the comparative advantage. Liu [10] argued that the competitiveness of future manufacturing operations depends on forward-looking thinking strategies and optimizing resource allocation and adjustment strategies to sustainably develop competitive potential, as analyzed at the enterprise level. Das [11] studied the international product trade related to automated industrial robots (AIR), the industrial Internet of Things (IIoT) and additive manufacturing (AM). The comparative advantage shown by the export of these products indicates the benefits of environmentally friendly production technology and further improves the country’s performance with regard to the relevant sustainable development goals, especially in developed countries. Fox [12] confirmed that the countries that have dominated the global manufacturing industry in recent decades continue to dominate physical production. Nand et al. [13] studied the status quo of sustainable manufacturing trade-offs that affect suppliers in industrialized and less developed countries and found that suppliers are facing increasing pressure to incorporate sustainability methods into international supply chains. Shen et al. [14] pointed out that China is an important ally of many countries in the global market because it has industrial strength in production and leading commodity import and export activities. Zhang [15] found that the development of oil and gas should become the main goal of China’s political pipeline trade with Mongolia and Central Asia, and the country’s competitive advantage in the export of traditional manufactured products should be enhanced, so as to improve its position in the global oil and gas field trade. Shi et al. [16] demonstrated that the integration of manufacturing subsidiaries into the global value chain has greatly improved innovation regarding low-carbon capabilities and has helped to achieve long-term competitive advantages.

The abovementioned scholars studied the sustainable international competitiveness of the manufacturing industry by taking different sectors of the manufacturing industry as the research objects. When it comes to international competitiveness, studies must involve the competitive relationship between many countries. Scholars have found that trade exchanges in the manufacturing industry can fully reflect the relationship between supply and demand. Both trade competitiveness and trade complementarity exist between supply and demand in the manufacturing industry. Tian [17] found that the Trade Complementarity Index between China and the five Central Asian countries is relatively high through the investigation of the trade competitiveness and complementarity between China and these five Central Asian countries. Zhan and Jia [18] found that the trade complementarity of consumer goods between China and emerging economies may be stronger. Chen and Lian [19] argued that the competition and integration between China and ASEAN in the field of high-tech products are stronger. Hu and Zheng [20] found that the trade complementarity between China and countries along the “Belt and Road” is greater than the trade competitiveness. Wang and Ying [21] found that the competition and interests of China and developed countries in the electronic and optical instrument industry coexist, and China has trade dependence on developed countries. Jiang and Wang [22] studied the problem of Central Asia and found that capital-intensive products represent an export advantage for China, while resource-intensive products represent an export advantage for Central Asia, and the trade between Central Asia and China is highly complementary. Chen and Xu [23] argued that industrial products represent an export advantage for China with regard to South Asia; primary and semi-finished products represent an export advantage for South Asia with regard to China; and the trade structures of the two countries are complementary. Zheng et al. [24,25] found that the trade complementarity between China and Latvia, Estonia, Lithuania, Poland, the Czech Republic, and Hungary is mainly manifested in labor-intensive products, while the trade complementarity between these countries and China is manifested in resource-intensive products. Chen et al. [26] empirically found that the “Belt and Road” initiative between China and the “Belt and Road” countries has significantly promoted the trade growth between China and the “Belt and Road” countries. Another article by Chen et al. [27] investigated the agricultural trade between these countries and China, which is complementary and competitive with the Comprehensive and Progressive Agreement of the Trans-Pacific Partnership (CPTPP). Edjah et al. [28] studied the comparative trade interests and complementarities of 20 major agricultural products between China and Ghana and found that Ghana has stronger comparative advantages than China. Liu et al. [29] found that the complementarity and competitiveness of agricultural commerce in the “Belt and Road” countries tend to coexist, and the density of competitive networks and complementary networks has increased. Tang et al. [30] found that China and the European Union have significant trade complementarity in the low-tech field, and China and ASEAN have high trade complementarity in the high-tech electronics and electrical field. Nurgazina et al. [31] found that the complementarity of 28 agricultural products traded between China and Kazakhstan needs to be improved. Tian et al. [32] found that Vietnam’s imports from China are extremely beneficial to Vietnam’s category 0 imports, while Vietnam’s exports to China are highly complementary to China’s category 2 imports. Wang et al. [33] suggested that Xinjiang, China, and Pakistan establish a highly complementary supply chain import and export cooperation mechanism.

The above-mentioned scholars studied the trade competition and trade complementarity of different industries among countries based on the trade exchanges of agricultural products and other commodities between Central Asia, South Asia, ASEAN, the European Union, the “Belt and Road” countries, and China. So, how we can further understand whether the trade between two countries is maximized and the degree of trade tightness that two countries may establish in the future are the core issues that scholars have further explored. Wu and Feng [34] analyzed the bilateral trade integration between ASEAN and China and found that the economic interdependence between China and ASEAN, with investment and trade as the core, continued to deepen from 2012 to 2020. Li [35] found that the product market competition between China and South Korea is increasingly fierce, and the industrial complementarity and China’s rich resource endowment provide new ideas and directions for the further development of the economic and trade relations between these two countries. Shi and Zhang [36] found from the data in 2016 that the export trade potential between China and Brunei, Indonesia, Laos, the Philippines, and Thailand belongs to the category of incredible prospects; the trade between China and Myanmar belongs to the category of potential development; and the trade between China and Cambodia, Vietnam, Singapore, and Malaysia belongs to the category of potential remodeling. Tian [37] found that the resistance of China’s export trade to Nepal is greater than the opposition to bilateral trade, and the possibility of import trade between Nepal and China is huge. Parteka and Wolszczak-Derlacz [38] empirically analyzed the characteristics and openness of the markets of Poland and its expanding EU partners from 1995 to 2006, which stimulated the potential of Polish trade.

To sum up, scholars mainly study the international competitiveness and trade status of the manufacturing industry as a whole or a large sector of the manufacturing industry from the perspectives of the comparative advantage, trade complementarity, and trade integration of sustainable international competitiveness. Scholars not only agree that mastering key core technologies is fundamental for manufacturing power and global trade; they also agree that only by constantly using comparative advantages to expand new markets can trade opportunities be increased and advantageous industries develop sustainably. At present, most scholars carry out research from the perspective of the industry itself, the manufacturing industry as a whole, or a specific manufacturing industry sector, and only a few studies carry out research at the level of the key equipment and components, representing key core technologies. This work took the key equipment and components that represent the most scientific and technological content and core competitiveness in the HSR industry as the research object and took the HSR powers possessing HSR technology and the “Belt and Road” countries displaying great demand for HSR as the trade objects to carry out research with theoretical and practical significance.

3. Research Methods and Data Sources

3.1. Methods of Research

Revealed Comparative Advantage Index. The so-called Revealed Comparative Advantage Index (RCA) refers to the ratio between the share of a country’s exports of a certain commodity within its total export value and the share of this commodity’s exports within the world’s total export volume. It focuses on analyzing the international competitiveness of the industry using the trade data of the country or region. The formula is as follows:

$$\mathrm{RCA}=(x_{ij}/\sum x_{ij})/x_{wj}/\sum x_{wj}$$

(1)

In the above equation, $x_{ij}$ represents the export amount of key equipment and components j of HSR in country i, while $x_{wj}$ is the export amount of key equipment and components j of HSR in the world. $\sum x_{ij}$ represents the total export volume of key equipment and components of HSR in country i. $\sum x_{wj}$ represents the total export volume of key equipment and components of HSR in the world.

Trade Complementarity Index. The Trade Complementarity Index reflects the trade complementarity between national exports and national imports. Every country has its strengths and weaknesses. By taking advantage of its own advantages, a country can improve itself. Based on the research of Balassa [39] and Yu [40], the Trade Complementarity Index is expressed as $C_{ij}^k$, and the specific calculation formula is as follows:

$$C_{ij}^k={RCA}_{xi}^k\times {RCA}_{mj}^k$$

(2)

where ${RCA}_{xi}^k$ represents the trade comparative advantage of k-type products of country i measured by exports. ${RCA}_{xi}^k=(X_{ik}/X_i$)($W_k/W$), where $X_{ik}$ refers to the export volume of k-type products in country i and $X_i$ represents the total export volume of all goods of country i. $W_k$ represents the total world exports of category k products, while W represents the total world exports of all goods. The greater the ${RCA}_{xi}^k$, the greater the proportion of category k products in the total exports of country i, indicating that country i has more comparative advantages in the export of category k products. ${RCA}_{mj}^k$ indicates the comparative disadvantage of k-type products in country j measured by imports. ${RCA}_{mj}^k=$($M_{jk}/M_j$)($W_k/W)$, where $M_{jk}$ refers to the import value of k-type products in country j and $M_j$ refers to the total imports of all goods of country j. The greater the ${RCA}_{mj}^k$, the greater the proportion of category k products in the total imports of country j, which means that country j has a comparative disadvantage in the import of category k products. $C_{ij}^k$ refers to the Trade Complementarity Index between the exports of country i and the imports of country j in category k commodities.

Trade Integration Index. The Trade Integration Index (TII), as a bilateral concept, is a comprehensive indicator that is usually used to measure the heavy dependence on trade between countries. It was first proposed by Brown and was then improved by Kojima [41]. Wang and Feng [42] also used the Trade Integration Index to study the trade competitiveness and complementarity of China, Japan, and South Korea’s manufacturing industry. The specific formula is as follows:

$${TII}_{ij}^k=\left(X_{ij}^k/X_{iw}^k\right)/\left[M_{jw}^k/(M_{ww}^k-{\mathrm{M}}_{\mathrm{i}\mathrm{w}}^{\mathrm{k}})\right]$$

(3)

where ${TII}_{ij}^k$ indicates the trade combination degree of the exports of country i to industry k of country j, $X_{ij}^k$ represents the export volume of k industry in country i to country j, and $X_{iw}^k$ represents the export volume of k industry in country i to the world. $M_{iw}^k$ refers to the import volume of k industry in country i, $M_{jw}^k$ represents the total import volume of k industries in country j, and $M_{ww}^k$ refers to the total import volume of world k industry. When ${TII}_{ij}^k$ > 1, it indicates that the exports of industry k in country i are highly dependent on the imports of country j, and the trade relationship between country i and country j is close. When ${TII}_{ij}^k$ < 1, it indicates that the exports of industry k in country i are less dependent on the imports of country j, and the trade ties between country i and country j are loose. The closer ${TII}_{ij}^k$ is to 0, the fewer trade ties there are between country i and country j.

Predictive model. The ARIMA (p, d, q) model is essentially a combination of a differential operation and the autoregressive moving average model (ARMA (p, q)). Let Y be a set of given sample sequences that do not meet the stationarity condition. The d-order difference transforms the non-stationary time series into a stationary time series and then estimates the order parameters of the stationary time series to obtain the values of p and q. Then, the ARMA (p, q) model is used to predict and analyze the time series. If the sequence W = VY after differential change meets the ARMA model conditions, then Y undergoes the ARIMA process. The specific expansion form is as follows:

$$W_t ={\varnothing }_1{W}_{t-1}+{\varnothing }_2{W}_{t-2}+\dots +{\varnothing }_p{W}_{p-1}+{\epsilon }_1-{\theta }_1{\epsilon }_{t-1}{-\theta }_2{\epsilon }_{t-2}-\dots -{\theta }_q{\epsilon }_{t-q}$$

(4)

Represented by the sequence y_t, we can obtain

$$Y_t-Y_{t-1}={\varnothing }_1(Y_{t-1}-Y_{t-2})+{\varnothing }_2(Y_{t-2}-Y_{t-3})+\dots +{\varnothing }_p(Y_{t-p}-Y_{t-p-1})+{\epsilon }_t-{\theta }_1{\epsilon }_{t-1}-{\theta }_2 {\epsilon }_{t-2}-\dots -{\theta }_q{\epsilon }_{t-q}$$

(5)

3.2. Sources of Data

The data were sourced from the UN COMTRADE database, and the names of the nine key pieces of equipment and components correspond to the six-digit codes of the International Customs Import and Export Product Classification Standard HS, namely axle wheels and components (860719); air brakes and components (860721); other brakes and components (860729); driving bogies (860711); other bogies (860712); maintenance or service vehicles (860400); traffic management equipment and components (860800); hooks, connectors, buffers, and components (860730); and electric locomotives (860110). This study selected data from 2013 to 2022 for analysis and argumentation.

4. Empirical Results

4.1. Comparative Analysis of the International Trade Competitiveness of Key Equipment and Components of China’s HSR

This section calculates the mean value of the RCA of the dominant comparative advantage of key equipment and components in 18 HSR powers from 2013 to 2022, as shown in

Table 1. RCA of international competitiveness of key equipment and components of HSR powers.

2013–2022 RCA Mean	Electric Locomotives	Maintenance or Service Vehicles	Driving Bogies	Other Bogies	Axle Wheels and Components	Air Brakes and Components	Other Brakes and Components	Hooks, Connectors, Buffers, and Components	Traffic Management Equipment and Components
CHN	1.77	0.55	0.13	0.93	1.07	0.36	0.72	1.96	1.36
JPN	N/A	0.15	2.46	1.58	1.90	0.49	0.66	1.26	1.37
KOR	N/A	0.65	0.25	N/A	0.94	0.22	0.32	0.20	1.01
USA	N/A	1.37	0.24	0.19	1.58	0.59	1.43	1.46	0.69
MEX	N/A	N/A	N/A	N/A	1.55	0.97	N/A	3.50	0.12
CAN	N/A	0.93	0.24	0.15	2.02	0.52	1.35	0.38	0.81
GER	2.26	0.77	1.11	1.24	0.56	1.63	0.64	0.95	0.57
AUT	N/A	3.18	3.06	1.61	0.21	0.92	0.13	0.02	0.58
ITA	N/A	1.51	0.30	0.10	1.40	1.34	1.40	0.03	1.14
ESP	1.68	0.72	0.63	0.73	1.02	1.11	0.26	0.07	1.90
NED	N/A	0.61	4.29	N/A	0.50	0.45	0.39	0.59	3.28
SUI	0.91	2.36	3.20	4.45	0.35	0.13	0.36	0.24	0.95
SWE	N/A	0.72	0.30	0.26	0.25	1.36	1.38	4.69	1.18
GBR	0.18	0.41	0.35	0.19	0.32	1.56	2.11	2.00	3.38
FRA	1.74	0.49	2.69	0.46	0.63	0.23	5.48	0.32	1.66
POL	N/A	0.13	0.29	1.35	0.88	0.21	1.12	5.52	0.71
CZE	0.10	0.09	0.23	1.32	2.10	0.66	0.53	0.92	0.29
SVK	0.65	N/A	N/A	2.99	1.67	0.63	1.45	0.69	0.53

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. Abbreviations of countries: Republic of China—CHN; Japan—JPN; Republic of Korea—KOR; the United States of America—USA; Mexico—MEX; Canada—CAN; Germany—GER; Austria—AUT; Italy—ITA; Spain—ESP; Netherlands—NED; Switzerland—SUI; Sweden—SWE; the United Kingdom—GBR; France—FRA; Poland—POL; Czech Republic—CZE; Slovakia—SVK. The abbreviations of countries in Table 2, Table 3, Table 4, Table 5 and Table 6 are the same.

. In the analysis, reference is made to the research methods of Tang and Liu [1]. RCA ≤ 0.8 means that the dominant comparative advantage is weak; 0.8 < RCA ≤ 1.25 indicates a slight dominant comparative advantage; 1.25 < RCA ≤ 2.5 indicates a strong explicit comparative advantage; and RCA > 2.5 indicates that the dominant comparative advantage is extremely strong. On the whole, the RCA of key equipment and components of China’s HSR is between 0 and 1.96. China’s RCAs of electric locomotives (1.77), hooks, connectors, buffers and components (1.96), and traffic management equipment and components (1.36) belong to the second-highest strength category, indicating that these products have strong international competitiveness. The RCAs of other bogies (0.93) and axle wheels and components (1.07) in China belong to the second-lowest strength category, indicating that these products have reasonably strong international competitiveness. China’s RCAs for maintenance or service vehicles, driving bogies, air brakes, and other brakes and components belong to the lowest strength category, indicating that these products have weak international competitiveness, especially for driving bogies (0.13) and air brakes (0.36), which have the weakest international competitiveness.

From the perspective of RCA > 2.5, Germany, Austria, the Netherlands, Switzerland, and France are the countries with extremely strong comparative advantages, and each of these countries has two types of key HSR equipment and components with extremely strong comparative advantages. Although Germany does not have extremely strong RCA values in the field of electric locomotives (2.26) and air brakes (1.63), it is the world leader in these areas. Through the above comparative analysis, we find that the international competitiveness of key equipment and components of China’s HSR is generally at the upper middle level, but it is undeniable that there is still a large gap compared with the leading level globally. Some of these areas obviously represent the weakness of the development of China’s HSR industry. Only by addressing these bottlenecks can we achieve the high-quality development of China’s HSR industry. At the same time, we can also see that the global HSR powers have different levels of performance in the trade of key equipment and components. No country can take the lead in all nine categories of key HSR equipment and components. Therefore, the development of the global HSR industry requires the cooperation of all countries, and mutual benefits and win–win relationships represent an inevitable trend in the sustainable development of the world’s HSR industry in the future.

4.2. Comparative Analysis of the Trade Complementarity of Key Equipment and Components of China’s HSR

The trade complementarity of goods can be reflected by the Trade Complementarity Index. If the Trade Complementarity Index is higher, it indicates that the import and export structure of the goods between the two countries has a high degree of fit, and vice versa. This section uses the Trade Complementarity Index $C_{ij}^k$ to compare and analyze the bilateral trade complementarity and fluctuation trends of nine types of key HSR equipment and components between China and 17 countries in 2013 and 2022. The selection of these two years for analysis is based on the desire to compare the changes and trends of $C_{ij}^k$ over the past 10 years. The calculation and analysis results are shown in Table 2 and Table 3.

4.2.1. The Trade Complementarity Relationship between China’s Exports and 17 Countries’ Imports

The larger the Trade Complementarity Index $C_{ij}^k$, the stronger the trade complementarity. The values of $C_{ij}^k$ in Table 2, which are dominated by Chinese exports, can be roughly divided into three stages, namely $C_{ij}^k<1, {1\le C}_{ij}^k<5, \mathrm{a}\mathrm{n}\mathrm{d} C_{ij}^k$ ≥ 5. By observing these values longitudinally, it is found that the $C_{ij}^k$ value of electric locomotives is relatively high—for example, 14.84 in AUT, 24.55 in SWE, and 11.19 in CZE—and there are many values in the range of 1 ≤${ C}_{ij}^k$< 5 relating to hooks, connectors, buffers and components, traffic management equipment and components, as well as other bogies and axle wheels and components. This indicates that the trade complementarity between China’s exports of these types of components and the imports of these types of components by various countries is strong, and the trade matching between the two countries is compatible. However, regarding maintenance or service vehicles, driving bogies, air brakes, and other brakes, the value of $C_{ij}^k$ is significantly lower than for the above categories. This indicates that the trade complementarity between China’s exports of these types of components and the imports of these types of components by other countries is weak, and the trade between the two countries is not matched. It is worth noting that the value of maintenance or service vehicles in 2013 was almost less than 1 or hovering around 1, indicating weak trade complementarity. However, by 2022, the value had significantly increased, indicating enhanced trade complementarity. The characteristics of the above values of $C_{ij}^k$ are consistent with Table 1, and China’s internationally competitive key HSR equipment and components can also establish close complementary trade relationships with most HSR powers.

Table 2. The Trade Complementarity Index $C_{ij}^k$ between China’s exports and 17 countries’ imports of key HSR equipment and components.

Country	Year	Electric Locomotives	Maintenance or Service Vehicles	Driving Bogies	Other Bogies	Axle Wheels and Components	Air Brakes and Components	Other Brakes and Components	Hooks, Connectors, Buffers, and Components	Traffic Management Equipment and Components
JPN	2013	N/A	1.21	0.00	N/A	0.04	0.07	0.22	0.16	0.58
	2022	N/A	3.37	0.04	0.00	0.06	0.12	0.05	0.28	0.47
KOR	2013	N/A	0.48	0.13	0.01	0.24	0.04	0.19	0.67	0.29
	2022	0.00	1.95	0.01	0.01	0.49	0.20	0.21	0.99	0.06
USA	2013	N/A	0.15	0.04	0.04	0.64	0.09	0.28	0.55	0.29
	2022	0.00	N/A	0.04	0.07	0.56	0.10	0.20	1.28	0.39
MEX	2013	0.00	0.52	0.00	0.24	2.83	0.29	2.31	3.19	0.74
	2022	N/A	N/A	N/A	N/A	4.18	0.58	1.38	10.05	0.54
CAN	2013	N/A	2.07	0.03	0.11	1.29	0.19	1.13	1.63	1.47
	2022	0.27	4.05	0.03	0.18	2.88	0.38	1.07	3.79	2.27
GER	2013	7.71	0.91	0.70	5.08	0.61	0.52	0.81	0.71	0.58
	2022	1.07	0.19	0.56	1.79	0.99	0.75	0.49	0.78	0.70
AUT	2013	1.78	2.77	0.01	11.01	2.78	1.67	0.78	1.79	2.43
	2022	14.84	2.30	0.28	1.95	2.51	2.39	2.15	2.26	3.63
ITA	2013	1.41	0.93	0.06	0.06	0.26	0.30	0.15	0.32	0.50
	2022	0.19	1.86	0.02	0.07	0.45	0.89	0.16	0.98	0.84
ESP	2013	0.16	0.54	0.32	0.05	0.30	0.30	0.34	0.45	0.36
	2022	9.40	1.10	0.03	0.06	0.33	0.63	0.23	0.92	11.89
NED	2013	0.15	0.05	0.00	0.00	0.15	0.06	0.05	0.07	0.47
	2022	0.00	0.08	0.00	N/A	0.12	0.00	0.00	0.31	0.18
SUI	2013	0.98	1.06	0.02	1.02	0.94	0.30	0.97	1.05	1.62
	2022	0.76	1.70	0.16	0.70	1.07	0.63	0.50	1.77	1.92
SWE	2013	24.55	0.21	0.08	0.31	2.17	0.43	0.86	3.88	2.05
	2022	3.31	5.01	0.08	0.44	0.65	0.87	0.36	1.34	2.45
GBR	2013	0.00	0.49	0.05	3.64	0.27	0.11	1.60	0.46	1.38
	2022	0.01	0.26	0.70	0.13	0.47	0.29	0.27	3.10	1.31
FRA	2013	N/A	1.42	0.05	0.06	0.57	0.25	2.60	0.81	0.99
	2022	0.00	0.24	0.02	0.05	0.86	0.30	2.16	1.37	0.79
POL	2013	1.00	0.32	0.03	4.48	0.69	0.28	0.55	3.46	0.66
	2022	1.63	0.25	0.21	1.05	2.17	0.53	0.50	4.69	0.72
CZE	2013	3.24	0.10	0.02	0.88	1.20	0.25	2.66	0.99	0.26
	2022	11.19	0.07	0.01	0.05	1.45	0.86	2.27	3.07	0.26
SVK	2013	9.15	0.34	0.01	0.97	1.86	0.72	0.27	3.99	1.44
	2022	0.18	1.58	0.04	0.57	5.93	3.00	0.93	9.61	0.39

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

Table 2. The Trade Complementarity Index $C_{ij}^k$ between China’s exports and 17 countries’ imports of key HSR equipment and components.

Country	Year	Electric Locomotives	Maintenance or Service Vehicles	Driving Bogies	Other Bogies	Axle Wheels and Components	Air Brakes and Components	Other Brakes and Components	Hooks, Connectors, Buffers, and Components	Traffic Management Equipment and Components
JPN	2013	N/A	1.21	0.00	N/A	0.04	0.07	0.22	0.16	0.58
	2022	N/A	3.37	0.04	0.00	0.06	0.12	0.05	0.28	0.47
KOR	2013	N/A	0.48	0.13	0.01	0.24	0.04	0.19	0.67	0.29
	2022	0.00	1.95	0.01	0.01	0.49	0.20	0.21	0.99	0.06
USA	2013	N/A	0.15	0.04	0.04	0.64	0.09	0.28	0.55	0.29
	2022	0.00	N/A	0.04	0.07	0.56	0.10	0.20	1.28	0.39
MEX	2013	0.00	0.52	0.00	0.24	2.83	0.29	2.31	3.19	0.74
	2022	N/A	N/A	N/A	N/A	4.18	0.58	1.38	10.05	0.54
CAN	2013	N/A	2.07	0.03	0.11	1.29	0.19	1.13	1.63	1.47
	2022	0.27	4.05	0.03	0.18	2.88	0.38	1.07	3.79	2.27
GER	2013	7.71	0.91	0.70	5.08	0.61	0.52	0.81	0.71	0.58
	2022	1.07	0.19	0.56	1.79	0.99	0.75	0.49	0.78	0.70
AUT	2013	1.78	2.77	0.01	11.01	2.78	1.67	0.78	1.79	2.43
	2022	14.84	2.30	0.28	1.95	2.51	2.39	2.15	2.26	3.63
ITA	2013	1.41	0.93	0.06	0.06	0.26	0.30	0.15	0.32	0.50
	2022	0.19	1.86	0.02	0.07	0.45	0.89	0.16	0.98	0.84
ESP	2013	0.16	0.54	0.32	0.05	0.30	0.30	0.34	0.45	0.36
	2022	9.40	1.10	0.03	0.06	0.33	0.63	0.23	0.92	11.89
NED	2013	0.15	0.05	0.00	0.00	0.15	0.06	0.05	0.07	0.47
	2022	0.00	0.08	0.00	N/A	0.12	0.00	0.00	0.31	0.18
SUI	2013	0.98	1.06	0.02	1.02	0.94	0.30	0.97	1.05	1.62
	2022	0.76	1.70	0.16	0.70	1.07	0.63	0.50	1.77	1.92
SWE	2013	24.55	0.21	0.08	0.31	2.17	0.43	0.86	3.88	2.05
	2022	3.31	5.01	0.08	0.44	0.65	0.87	0.36	1.34	2.45
GBR	2013	0.00	0.49	0.05	3.64	0.27	0.11	1.60	0.46	1.38
	2022	0.01	0.26	0.70	0.13	0.47	0.29	0.27	3.10	1.31
FRA	2013	N/A	1.42	0.05	0.06	0.57	0.25	2.60	0.81	0.99
	2022	0.00	0.24	0.02	0.05	0.86	0.30	2.16	1.37	0.79
POL	2013	1.00	0.32	0.03	4.48	0.69	0.28	0.55	3.46	0.66
	2022	1.63	0.25	0.21	1.05	2.17	0.53	0.50	4.69	0.72
CZE	2013	3.24	0.10	0.02	0.88	1.20	0.25	2.66	0.99	0.26
	2022	11.19	0.07	0.01	0.05	1.45	0.86	2.27	3.07	0.26
SVK	2013	9.15	0.34	0.01	0.97	1.86	0.72	0.27	3.99	1.44
	2022	0.18	1.58	0.04	0.57	5.93	3.00	0.93	9.61	0.39

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

Comparing these values horizontally on a national basis, the Trade Complementarity Index of nine key types of HSR equipment and components based on China’s export advantage is presented, and most countries have higher values in 2022 than in 2013. This indicates that for the same type of key HSR equipment or components, the 17 HSR powers prefer to import from China, and the larger the difference in the index between 2022 and 2013, the stronger the trade complementarity between the two countries and the more matched the trade relationship. After ten years of technological progress and innovation, China’s HSR manufacturing industry has expanded its export advantages. China can better leverage this advantage and establish stable complementary trade relationships with more countries in need, which will undoubtedly benefit the safety, stability, and sustainable international competitiveness of China’s HSR key equipment and component export industry chain.

4.2.2. The Complementary Relationship between China’s Imports and 17 Countries’ Exports

Through longitudinal observations of the Trade Complementarity Index measured using China’s import disadvantage, it was found that the $C_{ij}^k$ values of hooks, connectors, buffers, and components, as well as other bogies and axle wheels and components, were almost all lower in 2022 than in 2013. This indicates that the trade complementarity between China’s imports of these types of components and the exports of these types of components by various countries has weakened. These three categories are precisely the key types of equipment and component in China’s HSR that have international competitiveness and are mentioned in Table 1. After ten years of development, China’s imports are smaller than its exports, and its import disadvantage is narrowing. In the category of traffic management equipment and components, even though a few $C_{ij}^k$ values in 2022 are higher than those in 2013, the difference in values is between 0.1 and 0.3, displaying little impact on China’s import disadvantage. In terms of driving bogies, air brakes, and other brakes, most of the $C_{ij}^k$ values in 2022 are higher than those in 2013. Most increases are below 1, and China’s importing countries include most of these 17 countries, expanding its import channels.

Table 3. The Trade Complementarity Index $C_{ij}^k$ between China’s imports and 17 countries’ exports of key HSR equipment and components.

Country	Year	Electric Locomotives	Maintenance or Service Vehicles	Driving Bogies	Other Bogies	Axle Wheels and Components	Air Brakes and Components	Other Brakes and Components	Hooks, Connectors, Buffers, and Components	Traffic Management Equipment and Components
JPN	2013	N/A	0.01	0.01	0.12	3.07	0.19	0.03	3.12	0.21
	2022	N/A	0.03	0.07	0.01	0.23	0.40	0.31	0.15	0.32
KOR	2013	N/A	0.07	0.00	0.07	0.74	0.06	0.03	0.38	0.18
	2022	N/A	0.03	0.02	0.00	0.12	0.02	0.05	0.03	0.25
USA	2013	N/A	3.79	0.01	0.22	9.43	0.90	0.25	9.08	0.23
	2022	N/A	0.47	0.01	0.01	1.11	1.02	1.26	1.79	0.28
MEX	2013	N/A	0.09	N/A	0.06	3.08	0.70	0.01	9.45	0.00
	2022	N/A	N/A	N/A	N/A	0.20	0.44	0.43	0.83	0.04
CAN	2013	N/A	1.09	0.00	0.02	3.29	0.44	0.08	0.39	0.18
	2022	N/A	0.18	0.01	0.00	0.64	0.14	0.62	0.12	0.06
GER	2013	N/A	2.62	0.02	1.02	6.39	3.24	0.30	12.36	0.42
	2022	N/A	0.24	0.31	0.13	0.77	3.44	1.40	1.27	0.36
AUT	2013	N/A	67.72	0.13	7.04	18.86	16.80	0.21	1.82	1.87
	2022	N/A	6.01	6.10	0.98	1.15	14.36	1.45	0.10	2.12
ITA	2013	N/A	2.48	0.00	0.09	7.64	2.01	0.12	0.17	0.39
	2022	N/A	0.78	0.26	0.01	0.94	2.27	1.81	0.06	0.42
ESP	2013	N/A	1.65	0.01	3.71	7.08	0.67	0.10	0.25	1.54
	2022	N/A	0.10	0.07	0.02	0.98	2.47	0.50	0.24	1.08
NED	2013	N/A	0.00	0.00	N/A	0.09	0.03	0.00	0.02	0.09
	2022	N/A	0.02	0.02	0.00	0.01	0.07	0.04	0.04	0.08
SUI	2013	N/A	4.33	0.03	2.72	1.01	0.19	0.04	1.49	0.42
	2022	N/A	0.57	0.61	0.26	0.25	0.29	0.36	0.35	0.37
SWE	2013	N/A	0.73	0.00	0.04	2.23	1.41	0.35	32.73	0.48
	2022	N/A	0.43	0.02	0.05	0.17	2.68	0.19	3.18	0.40
GBR	2013	N/A	0.14	0.00	0.03	0.80	0.90	0.20	3.87	0.45
	2022	N/A	0.12	0.07	0.00	0.19	0.49	0.67	0.74	0.67
FRA	2013	N/A	0.60	0.03	0.18	3.07	0.21	0.71	2.08	0.48
	2022	N/A	0.05	0.17	0.04	0.51	0.38	6.21	0.34	0.56
POL	2013	N/A	0.32	0.00	0.06	4.09	0.38	0.47	49.13	0.84
	2022	N/A	0.06	0.09	0.26	0.63	0.54	0.87	5.50	0.16
CZE	2013	N/A	0.59	0.01	1.37	38.61	2.11	0.26	12.86	1.60
	2022	N/A	0.02	0.41	0.38	4.43	4.90	1.55	3.25	0.28
SVK	2013	N/A	0.81	N/A	1.03	4.29	0.31	0.17	1.36	0.04
	2022	N/A	N/A	0.07	0.12	2.29	3.69	1.15	1.86	0.03

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

Table 3. The Trade Complementarity Index $C_{ij}^k$ between China’s imports and 17 countries’ exports of key HSR equipment and components.

Country	Year	Electric Locomotives	Maintenance or Service Vehicles	Driving Bogies	Other Bogies	Axle Wheels and Components	Air Brakes and Components	Other Brakes and Components	Hooks, Connectors, Buffers, and Components	Traffic Management Equipment and Components
JPN	2013	N/A	0.01	0.01	0.12	3.07	0.19	0.03	3.12	0.21
	2022	N/A	0.03	0.07	0.01	0.23	0.40	0.31	0.15	0.32
KOR	2013	N/A	0.07	0.00	0.07	0.74	0.06	0.03	0.38	0.18
	2022	N/A	0.03	0.02	0.00	0.12	0.02	0.05	0.03	0.25
USA	2013	N/A	3.79	0.01	0.22	9.43	0.90	0.25	9.08	0.23
	2022	N/A	0.47	0.01	0.01	1.11	1.02	1.26	1.79	0.28
MEX	2013	N/A	0.09	N/A	0.06	3.08	0.70	0.01	9.45	0.00
	2022	N/A	N/A	N/A	N/A	0.20	0.44	0.43	0.83	0.04
CAN	2013	N/A	1.09	0.00	0.02	3.29	0.44	0.08	0.39	0.18
	2022	N/A	0.18	0.01	0.00	0.64	0.14	0.62	0.12	0.06
GER	2013	N/A	2.62	0.02	1.02	6.39	3.24	0.30	12.36	0.42
	2022	N/A	0.24	0.31	0.13	0.77	3.44	1.40	1.27	0.36
AUT	2013	N/A	67.72	0.13	7.04	18.86	16.80	0.21	1.82	1.87
	2022	N/A	6.01	6.10	0.98	1.15	14.36	1.45	0.10	2.12
ITA	2013	N/A	2.48	0.00	0.09	7.64	2.01	0.12	0.17	0.39
	2022	N/A	0.78	0.26	0.01	0.94	2.27	1.81	0.06	0.42
ESP	2013	N/A	1.65	0.01	3.71	7.08	0.67	0.10	0.25	1.54
	2022	N/A	0.10	0.07	0.02	0.98	2.47	0.50	0.24	1.08
NED	2013	N/A	0.00	0.00	N/A	0.09	0.03	0.00	0.02	0.09
	2022	N/A	0.02	0.02	0.00	0.01	0.07	0.04	0.04	0.08
SUI	2013	N/A	4.33	0.03	2.72	1.01	0.19	0.04	1.49	0.42
	2022	N/A	0.57	0.61	0.26	0.25	0.29	0.36	0.35	0.37
SWE	2013	N/A	0.73	0.00	0.04	2.23	1.41	0.35	32.73	0.48
	2022	N/A	0.43	0.02	0.05	0.17	2.68	0.19	3.18	0.40
GBR	2013	N/A	0.14	0.00	0.03	0.80	0.90	0.20	3.87	0.45
	2022	N/A	0.12	0.07	0.00	0.19	0.49	0.67	0.74	0.67
FRA	2013	N/A	0.60	0.03	0.18	3.07	0.21	0.71	2.08	0.48
	2022	N/A	0.05	0.17	0.04	0.51	0.38	6.21	0.34	0.56
POL	2013	N/A	0.32	0.00	0.06	4.09	0.38	0.47	49.13	0.84
	2022	N/A	0.06	0.09	0.26	0.63	0.54	0.87	5.50	0.16
CZE	2013	N/A	0.59	0.01	1.37	38.61	2.11	0.26	12.86	1.60
	2022	N/A	0.02	0.41	0.38	4.43	4.90	1.55	3.25	0.28
SVK	2013	N/A	0.81	N/A	1.03	4.29	0.31	0.17	1.36	0.04
	2022	N/A	N/A	0.07	0.12	2.29	3.69	1.15	1.86	0.03

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

Based on Table 2 and Table 3, it can be concluded that the bilateral trade complementarity of key equipment and components between China and the 17 HSR powers is increasing. The complementary trade relationship of key HSR equipment and components measured according to China’s export advantages is expanding. The network of China’s HSR industry chain is also expanding, thereby enhancing the resilience of the industry chain and reducing the risk of industry chain breakage caused by a country reducing or terminating its imports of key equipment and components for China’s HSR. The number of countries with complementary trade relationships relating to key HSR equipment and components, measured according to China’s import disadvantage, is increasing. The channels through which China imports from abroad are increasing in number, which will reduce or avoid disruptions to China’s HSR industry chain caused by supply interruptions from a single country. However, it must be noted that only AUT (6.01 and 6.10) has strong trade complementarity with China’s imported HSR maintenance or service vehicles and driving bogies. The Trade Complementarity Index of driving bogies imported by China and exported by other HSR powers in 2022 is less than 0.5. This indicates that there is a serious trade mismatch between China and other countries in these areas, which poses significant risks to the security of China’s HSR industry chain.

4.3. Analysis of the Trade Integration of Key Equipment and Components of China’s HSR

This section uses the United Nations UN COMTRADE database, the HS classification method, and Kojima’s revised formula to calculate the bilateral Trade Integration Index (TII) between China and 17 HSR powers from 2013 to 2022. It also measures the TII between China and 11 “Belt and Road” countries from 2013 to 2022, and then analyzes the trade tightness of key HSR equipment and components between China and these countries. The calculation results are shown in Table 4 and Table 5. Due to space limitations, TII data for 2014, 2016, and 2018 are not listed.

4.3.1. Bilateral Trade Integration of Key HSR Equipment and Components between China and 17 Manufacturing Powerhouses

On the left side of Table 4 is the TII (Trade Integration Index) of China’s key equipment and component exports to 17 HSR powers. The larger the TII value, the higher the trade dependence between the two countries. It can be seen that China’s TII for South Korea and China’s TII for the United States are both greater than 1, and a small portion of China’s TII for Japan and Mexico is greater than 1. This indicates that from 2013 to 2022, China had a high dependence on the trade of key HSR equipment and components from these countries. China has a high degree of trade dependence on South Korea, possibly due to the use of similar HSR technologies and similar key equipment and components in these two countries. The TII of China in relation to the United States generally shows a fluctuating trend of first rising and then falling; the reason for this fluctuation may be due to the fact that from 2013 to 2022, the United States, as China’s largest foreign trade partner, mainly imported Chinese products. With the overall improvement of China’s manufacturing capabilities and the diversified development of China’s foreign trade, China’s dependence on the exports of key HSR equipment and components from the United States has somewhat decreased since 2019.

Table 4. Bilateral Trade Integration Index (TII) of China’s and 17 countries’ key HSR equipment and components.

Countries		China’s Exports to 17 Countries							17 Countries’ Exports to China
	Time	2013	2015	2017	2019	2020	2021	2022	2013	2015	2017	2019	2020	2021	2022
JPN		0.75	0.21	1.01	1.02	0.47	0.24	0.40	6.51	5.01	3.43	4.91	9.06	6.33	3.93
KOR		5.10	1.54	4.52	2.11	1.91	2.90	2.10	0.04	0.51	0.28	0.45	0.10	0.08	6.13
USA		3.31	2.17	2.98	2.78	2.11	2.29	1.68	0.63	0.28	0.35	0.35	0.20	0.68	0.47
MEX		0.41	0.33	0.68	1.06	1.08	1.18	0.76	N/A	N/A	N/A	N/A	N/A	N/A	N/A
CAN		0.27	0.39	0.52	0.74	0.67	0.37	0.26	0.02	0.00	0.01	0.08	0.08	0.06	N/A
GER		0.12	0.08	0.12	0.18	0.30	0.31	0.22	1.23	1.95	1.50	1.45	1.05	1.48	2.02
AUT		0.01	0.01	0.02	0.05	0.07	0.08	0.08	0.75	0.25	0.15	0.31	0.22	0.12	0.10
ITA		0.39	0.10	0.15	0.09	0.22	0.15	0.15	1.23	2.14	3.00	2.08	2.72	2.43	1.63
ESP		0.25	0.17	0.47	0.68	0.47	0.47	0.16	0.20	0.23	0.28	0.89	0.02	0.34	2.89
NED		0.66	0.39	0.48	0.69	0.66	0.70	3.13	0.27	0.07	0.65	0.67	0.29	0.31	0.25
SUI		0.00	0.01	0.01	0.01	0.01	0.01	0.02	0.00	0.00	0.00	0.00	N/A	0.01	0.00
SWE		0.08	0.10	0.27	0.18	0.30	0.21	0.09	0.48	0.44	0.89	0.70	0.53	0.50	0.72
GBR		0.45	0.19	0.21	0.34	0.26	0.34	0.20	1.24	2.06	2.61	1.87	0.87	0.84	0.93
FRA		0.21	0.13	0.38	0.79	0.79	0.88	0.85	0.14	0.24	0.70	0.37	0.46	0.83	1.30
POL		0.19	0.02	0.29	0.34	0.24	0.16	0.27	0.18	0.34	0.96	0.64	0.61	0.72	0.56
CZE		0.26	0.04	0.08	0.28	0.06	0.06	0.07	0.44	0.58	0.76	1.14	0.61	0.82	1.09
SVK		0.01	0.00	0.03	0.03	0.04	0.05	0.05	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

Table 4. Bilateral Trade Integration Index (TII) of China’s and 17 countries’ key HSR equipment and components.

Countries		China’s Exports to 17 Countries							17 Countries’ Exports to China
	Time	2013	2015	2017	2019	2020	2021	2022	2013	2015	2017	2019	2020	2021	2022
JPN		0.75	0.21	1.01	1.02	0.47	0.24	0.40	6.51	5.01	3.43	4.91	9.06	6.33	3.93
KOR		5.10	1.54	4.52	2.11	1.91	2.90	2.10	0.04	0.51	0.28	0.45	0.10	0.08	6.13
USA		3.31	2.17	2.98	2.78	2.11	2.29	1.68	0.63	0.28	0.35	0.35	0.20	0.68	0.47
MEX		0.41	0.33	0.68	1.06	1.08	1.18	0.76	N/A	N/A	N/A	N/A	N/A	N/A	N/A
CAN		0.27	0.39	0.52	0.74	0.67	0.37	0.26	0.02	0.00	0.01	0.08	0.08	0.06	N/A
GER		0.12	0.08	0.12	0.18	0.30	0.31	0.22	1.23	1.95	1.50	1.45	1.05	1.48	2.02
AUT		0.01	0.01	0.02	0.05	0.07	0.08	0.08	0.75	0.25	0.15	0.31	0.22	0.12	0.10
ITA		0.39	0.10	0.15	0.09	0.22	0.15	0.15	1.23	2.14	3.00	2.08	2.72	2.43	1.63
ESP		0.25	0.17	0.47	0.68	0.47	0.47	0.16	0.20	0.23	0.28	0.89	0.02	0.34	2.89
NED		0.66	0.39	0.48	0.69	0.66	0.70	3.13	0.27	0.07	0.65	0.67	0.29	0.31	0.25
SUI		0.00	0.01	0.01	0.01	0.01	0.01	0.02	0.00	0.00	0.00	0.00	N/A	0.01	0.00
SWE		0.08	0.10	0.27	0.18	0.30	0.21	0.09	0.48	0.44	0.89	0.70	0.53	0.50	0.72
GBR		0.45	0.19	0.21	0.34	0.26	0.34	0.20	1.24	2.06	2.61	1.87	0.87	0.84	0.93
FRA		0.21	0.13	0.38	0.79	0.79	0.88	0.85	0.14	0.24	0.70	0.37	0.46	0.83	1.30
POL		0.19	0.02	0.29	0.34	0.24	0.16	0.27	0.18	0.34	0.96	0.64	0.61	0.72	0.56
CZE		0.26	0.04	0.08	0.28	0.06	0.06	0.07	0.44	0.58	0.76	1.14	0.61	0.82	1.09
SVK		0.01	0.00	0.03	0.03	0.04	0.05	0.05	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. The abbreviations of the country names are the same as in Table 1.

On the right side of Table 4 is the TII (Trade Integration Index) of key equipment and component exports from 17 HSR powers to China. It can be seen that Japan, Germany, and Italy all have a TII greater than 1 for China, and Japan has a higher TII value for China, indicating a higher degree of trade dependence on China. South Korea, the United Kingdom, France, and the Czech Republic have a few TIIs for China that are greater than 1. The reason for the large TII value is that at the beginning of China’s HSR development, four different technical standards of key HSR equipment and components were imported from Japan, Germany, Italy, and France. Between 2013 and 2022, these countries had a strong trade dependence on China.

4.3.2. Bilateral Trade Integration of Key HSR Equipment and Components between China and the Nations that Make Up the “Belt and Road”

Table 5 shows the bilateral Trade Integration Index (TII) of key HSR equipment and components between China and 11 “Belt and Road” countries. It can be seen from the left side of this table that most of China’s TII values for the “Belt and Road” countries are greater than 1, and China’s TII values for Laos and Vietnam are larger. This shows that China has a high trade dependence on the “Belt and Road” countries, especially Laos and Vietnam. This is because from 2013 to 2022, China attached great importance to the demand for HSR or increases in railway speed and the reconstruction and expansion of rail services in the “Belt and Road” countries. It can be seen from the right side of this table that the TII of Hungary to China is greater than 1, the TII of the other “Belt and Road” countries with data to China is greater than 1, and some values are larger. This shows that the “Belt and Road” countries have a potential trade dependence and demand for key equipment and components of China’s HSR in order to develop their own HSR industry.

Table 5. China and the “Belt and Road” countries’ key HSR equipment and component bilateral Trade Integration Index (TII).

Countries		China’s Exports to 11 Countries							11 Countries’ Exports to China
	Time	2013	2015	2017	2019	2020	2021	2022	2013	2015	2017	2019	2020	2021	2022
INA		1.22	0.69	0.89	1.10	1.49	3.29	7.42	N/A	N/A	N/A	0.01	0.00	3.26	0.73
LAO		54.75	2.29	24.43	0.11	8.59	16.52	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
VIE		2.89	1.32	9.88	5.04	9.40	5.69	12.37	N/A	N/A	N/A	N/A	N/A	N/A	N/A
SIN		0.70	6.94	0.38	0.57	1.82	4.44	1.95	0.05	0.03	0.50	0.14	1.37	1.15	4.37
MAS		3.56	1.25	3.66	2.75	3.57	1.50	3.68	0.73	0.01	1.56	3.73	4.68	1.80	0.67
THA		8.76	3.62	2.18	2.34	13.02	6.75	2.13	8.17	0.04	0.36	0.32	0.81	4.92	6.22
IND		4.07	1.66	4.23	6.32	4.05	2.42	3.34	0.12	0.14	0.11	0.27	0.17	0.58	1.85
PAK		1.40	0.94	4.41	3.85	2.03	7.25	1.19	N/A	N/A	N/A	N/A	N/A	N/A	N/A
TUR		0.48	0.81	1.08	1.87	1.35	3.22	0.90	N/A	N/A	0.00	0.03	0.05	0.10	0.26
HUN		0.10	0.01	0.04	0.07	0.12	0.30	0.07	2.46	2.33	2.26	1.11	1.69	1.66	1.14
SRB		0.01	0.02	3.06	0.54	0.29	0.91	0.53	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. Abbreviation of country: Indonesia—INA; Laos—LAO; Vietnam—VIE; Singapore—SIN; Malaysia—MAS; Thailand—THA; India—IND; Pakistan—PAK; Turkey—TUR; Hungary—HUN; Serbia—SRB. The abbreviations of countries in Table 5 and Table 6 are the same.

Table 5. China and the “Belt and Road” countries’ key HSR equipment and component bilateral Trade Integration Index (TII).

Countries		China’s Exports to 11 Countries							11 Countries’ Exports to China
	Time	2013	2015	2017	2019	2020	2021	2022	2013	2015	2017	2019	2020	2021	2022
INA		1.22	0.69	0.89	1.10	1.49	3.29	7.42	N/A	N/A	N/A	0.01	0.00	3.26	0.73
LAO		54.75	2.29	24.43	0.11	8.59	16.52	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
VIE		2.89	1.32	9.88	5.04	9.40	5.69	12.37	N/A	N/A	N/A	N/A	N/A	N/A	N/A
SIN		0.70	6.94	0.38	0.57	1.82	4.44	1.95	0.05	0.03	0.50	0.14	1.37	1.15	4.37
MAS		3.56	1.25	3.66	2.75	3.57	1.50	3.68	0.73	0.01	1.56	3.73	4.68	1.80	0.67
THA		8.76	3.62	2.18	2.34	13.02	6.75	2.13	8.17	0.04	0.36	0.32	0.81	4.92	6.22
IND		4.07	1.66	4.23	6.32	4.05	2.42	3.34	0.12	0.14	0.11	0.27	0.17	0.58	1.85
PAK		1.40	0.94	4.41	3.85	2.03	7.25	1.19	N/A	N/A	N/A	N/A	N/A	N/A	N/A
TUR		0.48	0.81	1.08	1.87	1.35	3.22	0.90	N/A	N/A	0.00	0.03	0.05	0.10	0.26
HUN		0.10	0.01	0.04	0.07	0.12	0.30	0.07	2.46	2.33	2.26	1.11	1.69	1.66	1.14
SRB		0.01	0.02	3.06	0.54	0.29	0.91	0.53	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Note: N/A indicates no data. Source: The authors performed their calculations according to UN COMTRADE data. Abbreviation of country: Indonesia—INA; Laos—LAO; Vietnam—VIE; Singapore—SIN; Malaysia—MAS; Thailand—THA; India—IND; Pakistan—PAK; Turkey—TUR; Hungary—HUN; Serbia—SRB. The abbreviations of countries in Table 5 and Table 6 are the same.

According to Table 4 and Table 5, China’s trade of key HSR equipment and components with the “Belt and Road” countries is highly integrated. The TII in Table 5 is relatively large, and China’s trade dependence on the “Belt and Road” countries is stronger. Between 2013 and 2022, China was able to meet the HSR market demand of the “Belt and Road” countries.

4.4. Prediction of Trade Prospects for Key Equipment and Components of China’s HSR

This part of the study used the pm. auto. Arima () code in Python 3.9.5 software to automatically build ARIMA models. Then, using the data from 2013 to 2022, we predicted the bilateral Trade Integration Index of key equipment and components for HSR between China and other countries from 2023 to 2027. Based on this, this paper analyzes the bilateral trade prospects of key equipment and components between China and the HSR powers in the next five years, and it also analyzes the bilateral trade prospects of the key equipment and components of HSR between China and the “Belt and Road” countries in the next five years. Each pair of countries establishes an ARIMA model. Due to space limitations, only the establishment and prediction process of the ARIMA model for the trade of key equipment and components of HSR in China with the United States is analyzed as an example, as shown in Figure 1.

Firstly, we perform a stationarity test on the aforementioned index sequence. It was found that, after the second-order differential transformation, the data fluctuated randomly around 0 without any obvious trend or period. Therefore, it is preliminarily judged that the second-order differential sequence is a stationary sequence, and the value of d in the model is 2. According to the Bess information criterion (BIC), we validate the model, select the model that minimizes the BIC function as the relatively optimal model, and determine ARIMA (1,2,0) as the optimal order parameter for the model. Secondly, we conduct a significance test on the model. From the output results, it can be seen that the LB test statistic and p-value of the ARIMA (1,2,0) model are significantly greater than 0.05, and the residuals follow a stationary random process with 0 as the mean, representing white noise disturbance. Therefore, the residual sequence of the fitting model belongs to the white noise sequence, and the fitting simulation is significantly effective. Again, we predict the ARIMA model, as shown in Figure 2. We observe the observed values, fitted values, and predicted values from 2013 to 2022, and then compare the two. The model fitting effect is good, so based on this, the trade integration degree of the key equipment and components of China’s HSR with the United States from 2023 to 2027 is predicted. The dotted line indicates that the dependence of the United States on the key equipment and components of China’s HSR will fluctuate and increase in the next five years.

We construct an ARIMA model for bilateral trade between China and other countries using the same methods and steps and predict the Trade Integration Index. The analysis results are shown in Table 6. It can be seen that from 2023 to 2027, the bilateral TII between China and countries such as South Korea, France, Singapore, and India will continue to be greater than 1. In the future, China will have close bilateral trade ties with these countries for key HSR equipment and components. China’s unilateral TII for the United States, the Netherlands, Malaysia, Indonesia, and Vietnam will basically be continuously greater than 1. In the future, China will have a high dependence on the trade of key HSR equipment and components with these five countries, while their trade dependence on China is not high. The unilateral TII of Germany, Italy, Spain, the United Kingdom, the Czech Republic, Thailand, and Hungary with regard to China will basically be continuously greater than 1 or close to 1. In the future, these countries will have a high dependence on the trade of China’s HSR key equipment and components.

Table 6. Prediction of the bilateral trade integration of key HSR equipment and components between China and various countries from 2023 to 2027.

Countries		2023	2024	2025	2026	2027	Countries		2023	2024	2025	2026	2027
	Time							Time
CHN vs. KOR		1.07	0.61	1.25	1.14	0.22	KOR vs. CHN		12.18	18.23	24.28	30.33	36.38
CHN vs. FRA		0.93	1.00	1.07	1.14	1.21	FRA vs. CHN		1.77	2.24	2.72	3.19	3.66
CHN vs. SIN		2.92	1.55	1.75	0.89	0.75	SIN vs. CHN		4.66	7.44	8.10	10.57	11.50
CHN vs. IND		4.26	5.19	6.11	7.04	7.96	IND vs. CHN		3.11	4.37	5.64	6.90	8.17
CHN vs. USA		1.76	1.24	1.24	0.79	0.72	USA vs. CHN		0.87	0.73	1.06	0.99	1.27
CHN vs. NED		5.55	7.98	10.40	12.83	15.25	NED vs. CHN		0.19	0.13	0.06	0.00	−0.06
CHN vs. MAS		4.21	2.55	4.58	4.89	3.59	MAS vs. CHN		−0.46	−1.58	−2.71	−3.84	−4.96
CHN vs. INA		10.34	14.47	17.39	21.53	24.45	CHN vs. VIE		13.50	13.90	18.40	19.22	21.26
CHN vs. GER		0.12	0.03	−0.06	−0.16	−0.25	GER vs. CHN		1.76	1.70	2.24	2.43	2.20
CHN vs. ITA		0.20	0.22	0.18	0.22	0.25	ITA vs. CHN		1.90	1.53	1.05	1.09	0.73
CHN vs. ESP		0.07	−0.09	−0.29	−0.41	−0.60	ESP vs. CHN		5.31	5.91	5.97	7.28	9.45
CHN vs. GBR		0.25	0.13	0.16	0.06	0.07	GBR vs. CHN		1.02	1.11	1.20	1.30	1.39
CHN vs. CZE		0.07	0.07	0.07	0.07	0.07	CZE vs. CHN		1.51	1.07	1.04	1.15	1.75
CHN vs. THA		−3.37	−8.40	−13.7	−18.8	−24.1	THA vs. CHN		7.51	8.80	10.10	11.39	12.69
CHN vs. HUN		0.22	0.15	0.20	0.18	0.20	HUN vs. CHN		1.27	1.25	0.97	0.94	0.90
CHN vs. AUT		0.10	0.10	0.12	0.12	0.13	AUT vs. CHN		0.02	−0.02	−0.09	−0.13	−0.19
CHN vs. SWE		−0.07	0.02	−0.08	−0.18	−0.32	SWE vs. CHN		0.58	0.47	0.40	0.50	0.43
CHN vs. JPN		0.00	−0.13	−0.15	−0.45	−0.57	JPN vs. CHN		1.53	−0.87	3.26	−5.66	−8.06
CHN vs. POL		0.37	0.48	0.59	0.69	0.80	POL vs. CHN		0.20	0.12	0.09	−0.09	−0.32
CHN vs. MEX		0.69	0.39	0.23	−0.02	−0.20	CHN vs. CAN		−0.01	−0.15	−0.39	−0.55	−0.78
CHN vs. SRB		0.81	0.65	0.78	0.72	0.79	CHN vs. SUI		0.01	0.01	0.01	0.02	0.01

Note: The actual value of the Trade Integration Index (TII) can be infinitely close to 0, and predicted negative values in this table indicate a trend. Data source: Predicted using Python based on Table 4 and Table 5. The abbreviations of the country names are the same as in Table 1 and Table 5.

Table 6. Prediction of the bilateral trade integration of key HSR equipment and components between China and various countries from 2023 to 2027.

Countries		2023	2024	2025	2026	2027	Countries		2023	2024	2025	2026	2027
	Time							Time
CHN vs. KOR		1.07	0.61	1.25	1.14	0.22	KOR vs. CHN		12.18	18.23	24.28	30.33	36.38
CHN vs. FRA		0.93	1.00	1.07	1.14	1.21	FRA vs. CHN		1.77	2.24	2.72	3.19	3.66
CHN vs. SIN		2.92	1.55	1.75	0.89	0.75	SIN vs. CHN		4.66	7.44	8.10	10.57	11.50
CHN vs. IND		4.26	5.19	6.11	7.04	7.96	IND vs. CHN		3.11	4.37	5.64	6.90	8.17
CHN vs. USA		1.76	1.24	1.24	0.79	0.72	USA vs. CHN		0.87	0.73	1.06	0.99	1.27
CHN vs. NED		5.55	7.98	10.40	12.83	15.25	NED vs. CHN		0.19	0.13	0.06	0.00	−0.06
CHN vs. MAS		4.21	2.55	4.58	4.89	3.59	MAS vs. CHN		−0.46	−1.58	−2.71	−3.84	−4.96
CHN vs. INA		10.34	14.47	17.39	21.53	24.45	CHN vs. VIE		13.50	13.90	18.40	19.22	21.26
CHN vs. GER		0.12	0.03	−0.06	−0.16	−0.25	GER vs. CHN		1.76	1.70	2.24	2.43	2.20
CHN vs. ITA		0.20	0.22	0.18	0.22	0.25	ITA vs. CHN		1.90	1.53	1.05	1.09	0.73
CHN vs. ESP		0.07	−0.09	−0.29	−0.41	−0.60	ESP vs. CHN		5.31	5.91	5.97	7.28	9.45
CHN vs. GBR		0.25	0.13	0.16	0.06	0.07	GBR vs. CHN		1.02	1.11	1.20	1.30	1.39
CHN vs. CZE		0.07	0.07	0.07	0.07	0.07	CZE vs. CHN		1.51	1.07	1.04	1.15	1.75
CHN vs. THA		−3.37	−8.40	−13.7	−18.8	−24.1	THA vs. CHN		7.51	8.80	10.10	11.39	12.69
CHN vs. HUN		0.22	0.15	0.20	0.18	0.20	HUN vs. CHN		1.27	1.25	0.97	0.94	0.90
CHN vs. AUT		0.10	0.10	0.12	0.12	0.13	AUT vs. CHN		0.02	−0.02	−0.09	−0.13	−0.19
CHN vs. SWE		−0.07	0.02	−0.08	−0.18	−0.32	SWE vs. CHN		0.58	0.47	0.40	0.50	0.43
CHN vs. JPN		0.00	−0.13	−0.15	−0.45	−0.57	JPN vs. CHN		1.53	−0.87	3.26	−5.66	−8.06
CHN vs. POL		0.37	0.48	0.59	0.69	0.80	POL vs. CHN		0.20	0.12	0.09	−0.09	−0.32
CHN vs. MEX		0.69	0.39	0.23	−0.02	−0.20	CHN vs. CAN		−0.01	−0.15	−0.39	−0.55	−0.78
CHN vs. SRB		0.81	0.65	0.78	0.72	0.79	CHN vs. SUI		0.01	0.01	0.01	0.02	0.01

Note: The actual value of the Trade Integration Index (TII) can be infinitely close to 0, and predicted negative values in this table indicate a trend. Data source: Predicted using Python based on Table 4 and Table 5. The abbreviations of the country names are the same as in Table 1 and Table 5.

Overall, in the next five years, China will pay special attention to maintaining its trade relationships with South Korea, France, Singapore, India, and Indonesia and will promote the development of the bilateral trade of key HSR equipment and components in accordance with the predicted trend. At the same time, China should pay more attention to its trade relationships with the “Belt and Road” countries, so as to make the trade of key equipment and components of HSR more competitive in the “Belt and Road” market. For countries with a TII less than 1, the bilateral or unilateral trade links between China and these countries regarding key HSR equipment and components are loose, making it difficult to establish a close trade dependency relationship in the short term.

5. Conclusions

From 2013 to 2022, the competitiveness of the trade of China’s nine types of key HSR equipment and component in the international market gradually increased. Electric locomotives, hooks, couplings, buffers and components, traffic management equipment and components, axles wheels and components, and other bogies manufactured in China are all highly competitive in international trade. Maintenance or service vehicles, driving bogies, air brakes, and other brakes and components manufactured in China have weak competitiveness in international trade, especially driving bogies.

This trade complementarity research based on China’s export advantage found that the trade complementarity in 2022 was greater than that in 2013 and found that the unilateral trade complementarity between China and other HSR powers regarding the five categories of key equipment and components with strong international competitiveness was still strong. The unilateral complementary trade relationships between China and other HSR powers regarding the four categories of key equipment and components with weak international competitiveness were still weak. The study of trade complementarity with China’s imports as a disadvantage found that the intensity of trade complementarity of China’s key equipment and components with international competitiveness in 2022 was less than that in 2013. This shows that China has consolidated its original advantages, reducing imports and expanding its export advantages. The trade complementarity of China’s original key equipment and components with weak international competitiveness increased, and the value in 2022 was greater than that in 2013, and more countries were matching in pairs. This shows that China has increased the number of countries it imports vulnerable categories of products from in order to effectively prevent the risk of supply interruption.

From 2013 to 2022, China’s unilateral trade dependence on South Korea and the United States was close, which shows that China’s HSR technology is similar to that of South Korea. Considering the factors of procurement cost and geographical distance, China hopes to import key HSR equipment and components from South Korea, and China is also closely linked with the United States, its largest partner in trade. However, Japan, Germany, Italy, and France have a close trade dependence on China unilaterally. This is because, at the beginning of the construction of HSR, China mainly imported from these four countries, which need to occupy the Chinese market in the field of key equipment and components of HSR. From 2013 to 2022, countries along the “Belt and Road” attached great importance to HSR construction and railway reconstruction and expansion. China has a high degree of trade dependence unilaterally on countries along the “Belt and Road”, especially Laos and Vietnam. The unilateral trade dependence of the “Belt and Road” countries on China exists but is not continuous.

According to the prediction of this model, China and South Korea, France, Singapore, and India may have a bilateral trade dependency from 2023 to 2027. China may have a unilateral trade dependence on the United States, the Netherlands, Malaysia, Indonesia and Vietnam. Germany, Italy, Spain, the United Kingdom, the Czech Republic, Thailand and Hungary may have a unilateral trade dependence on China.

Due to the rapid changes in the international market’s competition environment, there have been unprecedented changes, and there is a risk of supply chain disruption. Therefore, it is necessary to comprehensively examine the trade pattern of the key equipment and components of the global HSR industry, optimize the import and export trade structure of the key equipment and components of HSR, and strengthen all-round international cooperation. At the same time, we should further study the market segmentation of key HSR equipment and components and gradually increase our understanding of international market competition so as to make full use of the advantages of China’s HSR industry chain and expand the international market in an all-round way.