Deep-well support breakthrough: Dual-Telescoping Columns Address Long-Stroke Requirements

Recently, Shandong Wantong Hydraulic Co., Ltd., a national-level "Little Giant" enterprise specializing in niche expertise and innovation (hereinafter referred to as "Wantong Hydraulic"), announced that its independently developed double-extended hydraulic pillar has entered large-scale production. Designed specifically to meet the demands of "high mining height and long-stroke support" in deep井 mines, this product features a two-stage telescopic structure, making it a core piece of equipment for efficient support in deep-shaft coal mines and metal mines.

The double-acting hydraulic pillar is made from a composite alloy steel material combining 27SiMn and 42CrMo. Both the inner and outer cylinders undergo integral forging followed by precision machining, resulting in exceptionally high compressive strength. This design enables the pillar to handle working pressures ranging from medium-to-high to high-pressure applications, making it ideal for large- and medium-sized mining operations with significant extraction heights in deep wells. The pillar features a dual wear-resistant treatment: "chrome-plated outer cylinder combined with laser cladding on the inner cylinder," significantly enhancing its resistance to corrosion and abrasion compared to single-acting pillars. Additionally, optimized layouts of the dual-speed locking mechanism and sealing components effectively address synchronization issues and leakage concerns during the two-stage extension process, dramatically extending the product's service life. Furthermore, the product supports a wide range of cylinder diameters and maximum extension strokes, catering to the diverse height requirements of various deep-well mining environments.

As one of the first companies listed on the Beijing Stock Exchange, Wantong Hydraulics holds both the Coal Mine Machinery and Equipment Safety Mark Certification (MA Certification) and the ISO9001 Quality Management System Certification. Specifically for its double-acting hydraulic props, the company has established a comprehensive safety management system covering the entire process—from raw materials to production and finally to finished products. This includes rigorous testing such as prop burst-pressure tests, tens-of-thousands-of-cycle extension-compression fatigue tests, and simulated underground high-temperature and high-humidity environment tests, ensuring that its products meet the stringent safety standards required for deep-well mining operations. Leveraging its specialized hydraulic production line tailored for mining applications, Wantong Hydraulics can now produce enough double-acting hydraulic props annually to fulfill the customized procurement needs of deep-well mines, while also offering significantly shorter delivery times for bespoke products.

In a deep井 coal mine in Shaanxi, hydraulic supports equipped with Wantong Hydraulic's double-extended single columns have been operating smoothly for several months, perfectly suited for medium-to-large-height longwall mining faces. The columns exhibit exceptionally low synchronization errors during extension and retraction, ensuring stable support resistance. As a result, the frequency of column replacements has significantly decreased compared to the original equipment, leading to improved mining efficiency. "Deep wells demand greater extraction heights, and the long stroke and high stability of our double-extended columns make them an ideal match for our operational scenarios," said the mine’s production manager. Additionally, the product is also being supplied to a metal mine in Yunnan, where it is used for supporting deep-well mining areas—performing reliably even under the challenging conditions of elevated underground temperatures and high humidity.

As the proportion of deep-shaft mine exploitation increases domestically, demand for double-acting hydraulic props will continue to grow. Moving forward, the company will develop smart double-acting hydraulic props equipped with wireless pressure monitoring systems, helping to drive the digital and intelligent transformation of mine support systems.