In the hydraulic support system of fully mechanized coal mining working face, the high-pressure fluid transmission pipeline is the core component supporting the whole support actions of lifting, moving and pushing scraper conveyor. Its explosion-proof compliance, anti-pulse impact performance and long-term wear resistance directly determine the continuous operation efficiency of the whole fully mechanized mining equipment and underground production safety. MSHA MT/T98 Mining Wire Spiral Hydraulic Hose, as an exclusive product that meets both MSHA coal mine safety certification in the United States and domestic coal industry MT/T98 standards, together with the Hydraulic Support High Pressure Rubber Hose Assembly formed by high-precision integrated crimping process, is a highly reliable compliant transmission solution for hydraulic systems in high-gas and high-impact coal mines.
The safety qualification requirements for hydraulic hoses in the coal mining industry are much higher than those in ordinary industrial scenarios, and ordinary industrial-grade high-pressure rubber hoses cannot pass the underground acceptance process of coal mine projects. This MSHA MT/T98 Mining Wire Spiral Hydraulic Hose strictly follows dual mining safety specifications from the material selection stage: the outer rubber adopts a mining-specific flame-retardant and antistatic formula, and its combustion performance and surface resistance parameters fully meet the MSHA federal coal mine safety requirements, while 100% matching all technical indicators of the domestic MT/T98 "Steel Wire Spiral Reinforced Hydraulic Rubber Hose and Hose Assembly" industry standard. After the product is delivered from the factory, MSHA certification documents and coal mine safety related test reports can be provided simultaneously, and the underground project compliance acceptance can be completed directly without additional supplementary qualification materials.
Different from ordinary single-layer or double-layer steel wire braided hydraulic rubber hoses, the reinforcement layer of this mining hose adopts 4 or 6 layers of high-tensile galvanized steel wire spiral winding structure. Relying on the stress advantage of multi-layer steel wire staggered winding, the rated working pressure of the whole series covers the range from 16MPa to 53MPa, and the anti-pulse cycle life is far more than 200,000 times. It is fully suitable for the instantaneous high-pressure impact conditions that frequently occur during the moving and lifting process of the hydraulic support, and early failures such as hose burst and steel wire breakage caused by long-term high-frequency pressure fluctuation will not occur.
The inner layer of the hose adopts special nitrile rubber resistant to emulsion, which has excellent chemical stability to water-based hydraulic media and mineral hydraulic oil commonly used in coal mines. It will not cause problems such as inner layer swelling and medium penetration after long-term use. The special formula of the outer rubber can resist frequent dragging and wear of coal cinder in the underground roadway and salt spray corrosion in high humidity environment. In the long-distance moving pipeline of the hydraulic support, the outer layer wear resistance life is more than 40% higher than that of the ordinary braided hose, which greatly reduces the daily replacement and maintenance frequency of the underground pipeline.
Aiming at the characteristics of limited on-site processing conditions and strict safety management and control requirements in coal mines, the supporting Hydraulic Support High Pressure Rubber Hose Assembly adopts the factory pre-crimping integrated molding process: before leaving the factory, the MSHA MT/T98 Mining Wire Spiral Hydraulic Hose and the mining-specific high-strength steel joints are integrally assembled by CNC high-precision crimping equipment. Each finished assembly has passed the pressure holding sealing test of 1.5 times the rated working pressure before leaving the production line, which completely eliminates the assembly defect risk caused by manual rubber stripping and manual crimping on site.
Users can directly connect the finished product to the hydraulic support pipeline system after receiving it, without carrying out complex processing operations in the underground roadway, which greatly shortens the underground installation operation time and avoids the safety hidden dangers caused by underground hot work and rubber debris residue. The whole series supports customized inner diameter, assembly length and joint form according to actual demands, covering all mainstream hydraulic support pipeline specifications from DN10 to DN152, and can meet the requirements of liquid inlet and return pipelines and control valve group supporting pipelines of fully mechanized mining working faces with different tonnages.
During the selection process, it is necessary to reserve a burst safety margin of no less than 4 times combined with the actual maximum working pressure of the underground hydraulic support, so as to avoid long-term operation under full pressure. During the installation process, ensure that the bending radius of the hose is not less than the minimum bending radius marked on the product, and it is forbidden to forcibly tighten the joint when the hose body is in a twisted state, otherwise the pulse fatigue life of the hose will be greatly reduced. In daily maintenance, it is necessary to regularly check whether the outer rubber has problems such as wear exposing steel wires and aging cracking. Replace the hose in time when hidden dangers are found, so as to avoid underground safety accidents caused by faulty operation.
