2 The current development status of fully hydraulic rock drilling rigs abroad
In 1920, Dorman, an Englishman, was the first to develop a hydraulic rock drill. It was not until 1970 that Montabert, a French company, developed the world's first practical hydraulic rock drill, H50, which was assembled on a hydraulic drill truck for mine drilling, and was soon produced and popularized. Due to the superior technical performance and perforation efficiency of hydraulic rock drills, companies around the world have launched a wave of research and development on hydraulic rock drills and related equipment. After decades of development, hydraulic rock drills have formed various machine series with hundreds of specifications, widely used in many fields such as mining, hydropower, tunnel transportation, etc.
Foreign manufacturers that develop and produce hydraulic rock drills mainly include Atlas Copco of Sweden (Atlas Copco), Sandvik (Sandvik) and FURUKAWA of Japan (Guhe), which have invested in the development of hydraulic rock drills and related supporting drilling rigs. After the acquisition of Ingersoll Rand, Atlas Copco's product sales volume has always occupied the first place in the world; After acquiring Tomrock, Sandvik's product technology level and quality are considered by the industry to be the world's top, and the rock drilling equipment produced by these two companies accounts for more than half of the global production.
These companies' products have undergone long-term technological accumulation, improvement, and development, and have reached a very high level in terms of material selection, design, and manufacturing technology. At present, whether it is underground or open-pit, excavation or mining, there are corresponding hydraulic rock drills available for selection. The competition in the market has prompted companies around the world to accelerate product upgrades and develop towards product series, diversification, greening and intelligence. In the early 1980s, Finland's Tamrock company only had three series of hydraulic rock drills. Currently, the company's products have developed to seven series, dozens of types, ranging from small handheld to ultra heavy, with a complete range of specifications, suitable for various occasions such as small hole rock drilling, stone profile mining, open-pit step excavation, anchor rod drilling, mining roadway excavation and engineering tunnel excavation, underground mining rock drilling, etc. Especially Atlas Copco in Sweden can flexibly modify certain models of products according to users' special requirements, and assemble them into specialized products with matching components that can be changed according to different environments in different regions and countries. Nowadays, the Cop series hydraulic rock drills produced by Atlas Copco have evolved from Cop1022 to the latest Cop4050 heavy-duty hydraulic rock drill. The impact power of Cop4050 can reach 40kW, and it is assembled on the Simba4450 series fully hydraulic drilling rig. It has been successfully used for deep hole mining and rock drilling in the Kiruna iron mine of Luki Company in Sweden, with a drilling hole diameter of 127mm, which is the working range of traditional down the hole impactors. At the same time, the Swedish Atlas Copco company's Boomer E3 (three arm) and Boomer E4 (four arm) are hydraulic excavation rock drilling rigs suitable for large and medium-sized tunnels and tunnels with a cross-sectional area of 205 m ². Even in the hardest rock conditions, the But 45 heavy-duty drilling arm can easily drill through.
Hydraulic rock drilling rig is developed on the basis of the fully developed and mature hydraulic rock drilling machine, in order to improve the rock drilling speed, reduce the labor intensity of workers, and improve the working environment. It has the advantages of high rock drilling efficiency, low energy consumption, and green environmental protection. At the 1987 Stockholm World Mining Exhibition, companies such as Rask, Atlas Copco, and Tamrock exhibited various models of single arm micro hydraulic rock drilling rigs, ushering in a period of rapid development for hydraulic rock drilling rigs. Medium and large hydraulic rock drilling rigs are commonly used in engineering fields such as underground mining, mining rock drilling, and tunnel rock drilling. Among them, the most representative ones are Rocket Boomer series rock drilling rigs produced by Atlas Copco of Sweden and T3RW-210-177Y rock drilling rigs produced by Kogawa of Japan. They have been recognized by many users for their obvious progressiveness, economy and safety. This has also attracted the successive research and development of numerous manufacturers around the world to a certain extent, further promoting the vigorous development of hydraulic rock drilling rigs. In the later new hydraulic rock drilling rigs, there have been many products equipped with automatic control, such as automatic adjustment of drilling rig positioning and drilling arm, automatic drilling, tool withdrawal and shutdown, prevention of tool jamming accidents, remote control operation, etc. This also represents a certain development trend, that is, hydraulic rock drilling rigs are developing towards more efficient, fast, green, intelligent and economical direction [4-6].
The following are the models and pictures of commonly used excavation drilling vehicles by well-known foreign brands:

Anbaituo Boomer E4 hydraulic rock drilling rig

Figure 3 Sandvik DD422iE hydraulic rock drilling rig

3 Development status of fully hydraulic rock drilling rig in China
The development of hydraulic rock drills in China started early. In the mid-1960s, Zhuzhou Dongfang Tool Factory and others began to develop hydraulic rock drills, which has a history of more than 50 years. From the late 1970s to the late 1980s, it reached its peak, gradually quieted down in the 1990s, and began to rise again in the mid-2000s.
In 1980, the first hydraulic rock drill YYG80 for production in China was successfully developed by Changsha Mining and Metallurgy Research Institute, Zhuzhou Dongfang Tool Factory and other units. It was assembled on CGJ2Y fully hydraulic drilling rig and underwent industrial testing at Xiangdong Tungsten Mine, passing ministerial level technical appraisal, thus opening the prelude to the development of hydraulic rock drills in China. More than 10 units, including Beijing University of Science and Technology, Central South University of Technology, Shenyang Wind Power Tool Factory, Tianshui Wind Power Tool Factory, and Xuanhua Wind Power Tool Factory, have successively developed hydraulic rock drills and supporting drilling rigs. By the late 1990s, China had obtained national certification for twelve models, including YYG80, YYGJ145 (imitating Cop1038H), YYT30, YYG250A, CYY20 (imitating French RPH200), and DZYG38B (imitating Cop1238ME). Among them, there are 5 types with impact energies below 150J, while the remaining 7 types have impact energies between 150-250J. Most of the drillable holes are between 40 and 50mm, with only YYG250A, YYGJ145, TYYG20, and DZYG38B hydraulic rock drills having drillable holes larger than 50mm, up to a maximum of 115mm. The main models that have already been mass-produced are YYG80, YYT30, and YYG90A. Among the 12 models, except for 3 models that were surveyed and imitated from models sold in foreign markets at that time, the rest were independently developed by China.
The CGJ25-YYG90 hydraulic rock drill, designed and researched by Central South University of Technology and manufactured by Guangdong Nonferrous Metallurgical Machinery Factory, was used in the Rucheng Tungsten Mine in 1988. It was combined with a shovel insertion rock loader and an overlapping shuttle car to form a mechanized excavation line, achieving a monthly footage of 250m in a 2.4m × 2.6m section and a steadily increasing excavation efficiency of over 1m/work shift. In 1991, it achieved a good result of a single unit and single shift footage of 5.4-6m in the Huanren Copper Zinc Mine. The HYD200 and HYD300 hydraulic rock drills, which are matched with the French Mercury series hydraulic drilling rig, are produced using technology introduced by the French Eimco Secoma company from Lianhuashan Nonferrous Metallurgical Machinery Factory. Their localization rate has reached 95%, and the main component impact piston has a service life of over 20000 meters. All indicators have reached the level of similar foreign models, and have formed mass production. They have been promoted and applied in Jiaojia Gold Mine, Sanshan Island Gold Mine, and some coal mines. The CTJY12-3 fully hydraulic tire type drilling rig produced by Tianshui Fengdong Tool Factory is equipped with three YYGJ145 high-power hydraulic rock drills, three AB741 hydraulic drilling arms, AT1541 hydraulic thrusters, and one AF321 hydraulic working platform. It is the largest underground rock drilling rig in China with the world's advanced level in the 1980s. Subsequently, Xuzhou Xugong Railway Equipment and China Railway Equipment began the research and development of three arm rock drilling rigs, which have been put into use on site and continuously improved and developed [6-7].
In summary, the development of hydraulic rock drills in China has taken a path that combines independent research and development with the introduction and digestion of advanced foreign technologies. After decades of development and exploration, it has initially formed its own product specifications and series, reaching a certain level. However, the stability index of most hydraulic rock drills produced by manufacturers is around 500m (without dismantling for maintenance), while the world's advanced Swedish products are set at 6000m. Therefore, there is still a significant gap between domestic hydraulic rock drills and international advanced levels, and imported models have not yet been fully localized, with key components still relying on imports. In addition, domestic hydraulic rock drills mainly exhibit a situation of multiple research and development units, multiple product appraisals, numerous technological achievements, limited market applications, and low sustained production.
At present, the first choice for hydraulic rock drilling equipment used in some large-scale projects such as mines, transportation tunnels, and hydropower in China is still products from well-known foreign companies such as Atlas Copco from Sweden and Tamrock from Finland (now Sandvik). Domestic rock drilling equipment still needs to be improved in product series, layout, details, reliability, appearance, and other aspects to narrow the gap with international advanced levels. There is no doubt that there is a huge gap between domestic and foreign rock drilling equipment products in terms of product positioning, design concepts, and process methods, which run through the entire process of new product development. So we should enhance our ability to innovate independently, narrow the quality gap, and strengthen the research and development of key components at the technical level to form high-quality products with multiple specifications, stable performance, and sustainable development.
Introduction to Domestic Full Hydraulic Rock Drilling Truck Manufacturers
4.1 Xuzhou Xugong Railway Equipment Co., Ltd. TZ Series
XCMG TZ series: TZ1, TZ2T, TZ3A hydraulic rock drilling rigs are mainly suitable for excavation and construction operations in tunnels, mines, and other underground engineering tunnels and tunnels; And it can carry out drilling and blasting holes, anchor bolt holes, slotting holes, installation of explosives, anchor bolts, air ducts and other operations. The maximum tunnel section can reach 180 square meters. XCMG iron drilling vehicles are continuously accelerating localization and independent intellectual property rights in hydraulic, electrical and mechanical systems, and technology and product quality are constantly improving.

Figure 4: XCMG TZ3A Three Arm Drilling Car

4.2 Jiangxi Xintong Machinery Manufacturing Co., Ltd. Series Drilling Car
Jiangxi Xintong drilling rig includes single arm, double arm, and three arm series, with various types of walking modes including rubber wheel, crawler, and rail wheel, suitable for different working conditions such as coal and non coal mine tunnels, tunnels, and tunnels. The supporting hydraulic rock drills are mainly French Montebe and domestic Lianhuashan HYD rock drills.

Figure 5 Jiangxi Xintong DT2-23 Double arm Drilling Vehicle

4.3 Zhejiang Kaishan Heavy Industry Co., Ltd. KJ series drilling rig
The Kaishan KJ series drilling vehicles mainly consist of tracked and rubber wheeled single arm drilling vehicles, with nearly ten types of drilling vehicles suitable for tunnel areas ranging from 5-35 square meters. They are mainly used for construction operations in non coal mine mountain tunnels and tunnel excavation holes.

Figure 6 KJ210 rock drilling rig from Kaishan Heavy Industry

4.4 Zhangjiakou Xuanhua Huatai Mining and Metallurgical Machinery Co., Ltd. Series Drilling Car
Huatai drilling rigs come in various types with complete functions, including vertical shaft drilling rigs, CMJ series coal mine rock tunnel drilling rigs, CYT series rock drilling rigs, anchor rod drilling rigs, etc. It includes various types such as rubber wheel, track type, and rail wheel type. Applicable cross-sectional area is 6-17 square meters.

Figure 7 Xuanhua Huatai CMJ1-14 type
Coal mine rock tunnel drilling truck

4.5 Jiangsu Aneng Drilling Equipment Technology Co., Ltd. Series Drilling Vehicles
Aneng Drilling mainly focuses on open-pit mining equipment such as excavation and modification drilling machines, excavation and modification down the hole drilling machines, splitting machines, and carbon dioxide fracturing equipment. It has now formed a series of production of excavation and modification products and continuously enriched mining technology methods. For underground tunnels, tunnels, and other structures, our products mainly consist of anchor rod drilling machines and single arm tracked hydraulic rock drilling rigs. Among them, the CMJ1-10 rock drilling rig is mainly used for blasting operations in hard rock tunnels of 4-10 square meters in coal and non coal mines, focusing on small machine bodies and wireless remote control operations to achieve mechanized mining of small tunnels and replace traditional manual wind drilling. The external dimensions of the device body (length x width x height) are 4.7 x 1.1 x 1.5m.  

Figure 8: Jiangsu Aneng Drilling CMJ1-10 Coal Mine Rock Drilling Truck

Figure 9: Excavator converted to drilling rig

Figure 10 Carbon dioxide fracturing equipment

5. Conclusion
At present, the development of hydraulic rock drills and their drilling rigs in China cannot meet the rapid pace of construction to a certain extent. At the same time, the rapid development has brought many challenges and opportunities to the rock drilling industry. As a member of the hydraulic drilling rig manufacturer, we are constantly pursuing product stability and innovative breakthroughs. The following are my personal thoughts and summary:
1. Learn from advanced equipment experience and concepts from abroad, enhance the operability, stability, and success rate of drilling of our own equipment, and truly achieve mechanization and automation of this construction step;
2. Based on market research and product experience accumulation, design and develop mechanized equipment that is in line with domestic construction development, such as anchor drills for large tunnels, with independent intellectual property rights and core competitiveness;
3. It is expected that China will enhance the research and development of core hydraulic rock drills, continuously improve product quality and serialization, and at the same time, drilling rig manufacturers will do a good job in matching hydraulic rock drills, such as continuously improving their understanding of hydraulic rock drills, fault analysis and solutions, optimizing the matching of control systems, strengthening the accuracy requirements of drilling rig components such as guide rails and drill guards, reducing their failure rates, and extending their service life;
4. Enterprises can actively utilize relevant national policies and establish external advantages such as industry university research cooperation to accelerate product research and upgrading.