WanTong Hydraulic Mining Hydraulic Supports: Strengthening the Comprehensive Mining Support Safety System and Empowering Efficient, Safe Coal Production

As a nationally recognized "Little Giant" enterprise specializing in niche, specialized, and innovative products—and a leading player in China's hydraulic industry—Shandong Wantong Hydraulic Co., Ltd. (hereinafter referred to as "Wantong Hydraulic") has been deeply engaged in the technology field of coal mine fully-mechanized mining support equipment. Recently, the company’s independently developed hydraulic pillars for mining applications have achieved large-scale deployment. Designed specifically to meet the demanding support conditions underground in coal mines—characterized by high pressure, severe off-center loading, intense corrosion, and abundant coal slime and dust—the product has made critical breakthroughs in areas such as consistent resistance-support precision, superior resistance to off-center loads, and exceptional sealing durability. These advancements have enabled the product to seamlessly integrate with mainstream domestic hydraulic supports, effectively addressing key challenges faced by major coal mines in core production regions like Shanxi, Shaanxi, and Inner Mongolia—including issues like "unstable support systems, frequent pillar damage, and ongoing maintenance needs." As a result, these hydraulic pillars have become indispensable core components for ensuring the stability of fully-mechanized mining faces and significantly boosting overall mining efficiency.

Targeting and overcoming the pain points in support systems, while ensuring technology is perfectly tailored to underground operational needs.

The hydraulic prop for mining applications serves as the "core load-bearing unit" of hydraulic support systems, playing a critical role in propping up the underground roof and effectively resisting the impact of mine pressure. Its performance directly determines the safety factor and production continuity of the fully mechanized mining face. Leveraging over two decades of accumulated expertise in hydraulic technology, Wantong Hydraulics has launched a targeted R&D initiative to address the most pressing challenges in underground support systems. Specifically, the company has innovatively developed a "High-Precision Constant-Resistance Pressure-Control System," which optimizes valve assembly design and enhances the pressure feedback mechanism. This breakthrough ensures that the working resistance of the prop remains stably within the designed range, preventing roof subsidence or prop overload damage caused by resistance fluctuations—and thereby meeting the diverse mine-pressure demands of coal seams with varying thicknesses. Additionally, to tackle the common issue of uneven loading in underground environments, Wantong Hydraulics has introduced an "Anti-Offset Cylinder Structure." By reinforcing the cylinder sidewalls and refining the piston-guidance design, this innovative solution significantly boosts the prop’s ability to withstand lateral loads, effectively mitigating cylinder deformation and piston-rod bending failures—problems often encountered in conventional props due to uneven loading conditions.

Materials and sealing are the "keys to durability" for mining hydraulic pillars. Specifically designed by Wantong Hydraulics to withstand the highly corrosive, coal-mud-laden environments found underground, these pillars are crafted from premium-grade special alloy steel that boasts exceptional fatigue resistance and rust-prevention properties. Before entering the factory, the steel undergoes rigorous multi-stage mechanical performance and corrosion-resistance testing. In the surface-treatment process, an innovative "multi-layered composite anti-corrosion technique" is employed, combining a chrome-plated layer with a phosphating-based rust-proof coating. This advanced approach significantly enhances the pillar's ability to resist coal-mud-induced corrosion and abrasion, thereby extending its service life underground. Meanwhile, the sealing system features a cutting-edge "coal-mud-resistant high-pressure sealing assembly," featuring a three-layer structure of "dust ring + primary seal + anti-extrusion ring." This design effectively prevents coal mud and dust from infiltrating the pillar interior, safeguarding against seal wear and subsequent fluid leakage—a common issue in conventional products. As a result, the sealing lifespan is markedly longer than traditional designs, reducing the frequency of underground maintenance and minimizing downtime.

Meanwhile, tailored solutions are provided by Wantong Hydraulics to meet the diverse requirements of various longwall mining scenarios: For high-mining-height working faces, long-stroke, high-strength hydraulic pillars have been developed to effectively support towering roof conditions. For thin-seam working faces, lightweight and compact pillars have been designed to fit into the limited installation spaces. And for working faces prone to dynamic pressure hazards, the pillars' impact resistance has been significantly enhanced, with additional cushioning structures incorporated to withstand sudden bursts of mine pressure, ensuring stable support across all operational environments.

Rigorous quality control throughout the entire process, safeguarding underground support safety.

Safety in roof support for fully mechanized mining faces is of paramount importance. Once a mine-used hydraulic prop fails, it could lead to serious safety hazards such as roof collapses. To address this, Wantong Hydraulics has established a dedicated quality control system specifically tailored for mine-used hydraulic props: At the raw material stage, specially formulated alloy steels are rigorously screened and must pass tests for tensile strength, bending resistance, impact toughness, and corrosion resistance—ensuring that material performance fully meets coal mine safety standards. During production, a combined process of "precision forging plus CNC deep-hole machining" is employed, achieving cylinder bore surface roughness levels that are outstanding within the industry, thereby guaranteeing smooth piston movement while minimizing localized stress concentrations. Additionally, a "dust-free assembly workshop" has been introduced during the assembly phase to prevent contaminants from compromising sealing performance, with critical component assembly precision controlled down to the micrometer level.

To simulate real underground support conditions, Wantong Hydraulics has established a dedicated testing platform: - A pressure test bench is used to replicate load conditions exceeding the rated working pressure, verifying the column's overload resistance. - A biased-load test bench applies lateral loads to assess its ability to withstand off-center forces. - A corrosion test chamber mimics the coal slime water environment found underground, ensuring the effectiveness of anti-corrosion performance. - A fatigue testing machine performs an extensive number of lifting and lowering cycles to validate long-term support reliability. Before leaving the factory, every mining hydraulic pillar undergoes a rigorous four-step inspection process: "no-load trial operation + high-pressure sealing test + comprehensive visual inspection + safety performance verification." Additionally, all products are certified by the National Mining Machinery Quality Supervision and Inspection Center, maintaining a 100% factory-pass rate and eliminating potential safety hazards at the source.

Deeply serving mining customers, with significant achievements in market applications.

To address the upgrade needs of aging hydraulic supports, Wantong Hydraulics also offers a "one-on-one customization and retrofit service": Our technical team conducts in-depth on-site surveys at mining locations to measure support parameters, then adjusts the stroke length, cylinder diameter, and connection methods of the existing supports based on their current structure and specific reinforcement requirements. This ensures a precise match between "old supports" and "new columns"—for instance, an older mine in Shanxi Province successfully upgraded the performance of its long-serving hydraulic supports to meet modern mining standards by replacing them with Wantong Hydraulics' advanced columns. This approach not only avoids the high costs associated with completely replacing the entire support system but also significantly reduces equipment modernization expenses. Moreover, to ensure uninterrupted production at mines, Wantong Hydraulics has established an "Emergency Response Mechanism for Mining Operations," setting up after-sales service centers in key coal-producing regions across China. These centers can provide remote technical support within 24 hours and arrange on-site repairs or replacements within 48 hours. Additionally, we offer a rotating stock of backup columns to minimize downtime and maximize operational efficiency, thereby cutting down on losses caused by equipment failures.

Anchor smart, green trends to drive product iteration and upgrades.

Facing the trends of intelligent and green transformation in the coal industry, Wantong Hydraulics is accelerating the iterative development of hydraulic support columns for mining applications. Currently, the company has launched research and development on an "intelligent monitoring-type mining hydraulic support column," which is designed to integrate embedded pressure, displacement, and temperature sensors inside the column. These sensors will transmit data—such as support load and column stroke—via a 5G wireless module in real time. Mining personnel can then remotely monitor the operational status of the columns through the fully mechanized face’s central control system, enabling them to proactively identify potential issues like abnormal loads or seal wear, thus facilitating "preventive maintenance" and further enhancing the safety of the support system. Meanwhile, to meet the demands of green mine construction, the company is also developing lightweight mining hydraulic support columns—using new high-strength, lightweight alloy materials to replace some traditional steel components. This innovation not only maintains robust load-bearing performance but also significantly reduces the column’s weight, thereby cutting down the overall energy consumption of hydraulic supports and helping mines achieve low-carbon production.

In the future, the company will continue to deepen its expertise in the field of mining hydraulic support systems, strengthening collaborative efforts with mining enterprises and research institutions across industry, academia, and research. Focusing on the core demands of "greater safety, enhanced reliability, and increased intelligence," we will further optimize the performance of mining hydraulic props, providing more competitive hydraulic support solutions that drive the intelligent transformation of the coal industry while safeguarding national energy security—and ultimately contributing to the achievement of China's "Dual Carbon" goals.