Hose Safety and Reliability in Mining
Hose Safety and Reliability in Mining
Manufacturers and users of underground mining equipment take safety and reliability seriously, which means specifying hydraulic should also be taken seriously.
The mining industry, known for its harsh and unforgiving environments, demands reliable, high-quality equipment to ensure safety and efficiency. Longwall mining, which accounts for around 50% of total underground production, has had the largest continual impact upon underground coal operations in the U.S. over the last two decades.
Longwall mining is an underground mining operation in which a large panel or block of coal spanning up to 1,500 ft across distances of two to three miles is extracted. Longwall mines are characterized by low ceilings and tight spaces in which workers must operate heavy machinery. Hydraulic-powered roof supports, also called shields, protect the working area of the mine by extending as a shearer cuts back and forth along the coal face. Once it is cut by the shearer, coal falls onto a large chain conveyor for transport to the mine. The movable hydraulic shields in longwall mines advance with the shearer throughout the mining process, enabling increased productivity as well as improved safety for miners.
Safety is imperative in the mining industry, particularly when it comes to the dangers of roof falls and lack of clean air in underground coal mines. It is vital for the equipment used in mining to be thoroughly tested to meet internationally approved MSHA standards and provide consistently reliable performance to ensure safety of operations and individuals in extreme environments.
High Performance for Mining
Because of the rigid safety and performance requirements for mining equipment, Parker Hannifin and other major hose manufacturers offer products designed specifically for mining applications. Parker’s GlobalCore 187 hose is a 1,000 psi (7 MPa) constant-working-pressure hose specifically engineered for the mining industry. ISO 18752 requires impulse testing at 133% maximum working pressure and 100°C for 200,000 cycles for standard and compact type hoses. GlobalCore 187 hose exceeds these requirements and can be used as a high-pressure return line or where other hoses may be overkill or requires a lower bending force.
Constant-working-pressure hoses contradict traditional hydraulic hoses, in which pressure rating decreases as the inside diameter increases. For instance, if the maximum pressure requirement 1,000 psi, you could specify one hose family operating with a constant working pressure of 1,000 psi across all diameters for your hydraulic system. Converting from various product lines to a singular hose family that provides constant working pressure across sizes means a simplified selection process as well as reduced inventories, maintenance costs, and downtime.
The unified GlobalCore series of ISO 18752 hoses as the first family of 1,000 psi-rated constant-working-pressure hydraulic hose sizes from −8 through −48 (½- though 3-in. ID), and with half the minimum bend radius specified by SAE and ISO 18752. This feature reduces overall hose assembly length, promotes easier routing in the restrictive areas of underground mines, and decreases the number of bent tube fittings necessary. The tighter bend radius capability also means longer hose life in applications where machinery movement causes sharp bending of hoses.
Wide Selection for Safety
Although today’s hydraulic hose performs better than ever, a lack of maintenance, equipment abuse, or unforeseen circumstances can lead to failure of any hydraulic hose. The risk of serious injury resulting from the uncontrolled release of high pressure hydraulic fluids is an ongoing concern. Hydraulic fluid injection injuries are caused by a release of pressurized hydraulic fluid penetrating the skin. A pinhole-sized leak can travel at the same velocity as a bullet—600 ft/sec. According to research, more than 10% of mine safety incidents in the United States involve fluid power systems, with 1% of those resulting in serious injury or death.