Analysis of support by hydraulic props in a longwall working
Performance and safety considerations of hydraulic roof support systems. Proceedings of 17th International Conference on Ground Control in Mining, Morgantown, WV, pp. 176-186. Manual of FLAC ...
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A proper routing
Before retrofitting or modifying high-pressure hydraulic lines on longwall mining equipment, it is important to apply safe hydraulic hose fitting and mounting principles, including the use of properly rated and sized couplers, filters, and hoses designed to handle longwall system specifications. SAFETY TIP – SAFE HYDRAULIC HOSE ASSEMBLY
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Mechanical analysis of the structure of longwall mining hydraulic
A column hydraulic cylinder, balance hydraulic cylinder, rear connecting rod, and shield beam were treated as simplexes in the model to simulate the bearing capacity of the structure. Xu et al. 5,6 investigated the bearing capacity of a two-column shield hydraulic support using a plane bar support system model. After analyzing the …
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Dynamics of Hydraulic Leg of Powered Longwall Support
K. Stoinski, "Joint operation of valve block with hydraulic leg of powered longwall support," in: Proceedings of Scientific and Technical Conference on Testing, Designing, Manufacturing, and Maintenance of Hydraulic Systems [in Polish], Gliwice, Szczyrk (2000). "Polish Standard PN-G-50041:1994. Labor protection.
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Longwall hydraulics failure prompts safety alert
Staff Writer February 18, 2010, 9:45 am. Industry and Investment NSW has issued a safety alert after the "catastrophic failure" of hydraulic isolation valves on a mine's longwall system, as ...
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Reducing risk of hose assembly failures
A recent survey out of the United States has shown more than 60% of longwall operations with shields in service for 4-6 years have developed significant …
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Safety alert: longwall hydraulic system over …
A longwall hydraulic system became over-pressurised, resulting in the catastrophic failure of hydraulic isolation valves and other fittings in the pump station. These failures …
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THE NIOSH SHIELD HYDRAULICS INSPECTION …
ABSTRACT. Longwall shields provide essential ground control in longwall mining, yet a high percentage of shields are operating at less than peak capacity and many at well …
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Development of a Hydraulic System for the Automatic …
A mechanical support in a longwall complex requires proper supervision and control of operating parameters because it is responsible for the safety of machines and workers. Its main functions are to protect the excavation against the adverse effects of rock mass and to move it along with the operational progress of the shearer and the scraper …
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High-pressure incident prompts safety alert
17 February 2010. The perils of high-pressure hydraulic power are well known in the industry, with up to 20 longwall miners injured every year. A high-force jet of hydraulic …
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Longwall |
is a leading manufacturer of construction, mining, forestry, and industrial heavy equipment. Longwall mining is an efficient mining method and using the right equipment can make it even more profitable. Joy …
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Analysis of the Pressure Increase in the Hydraulic …
One of the most essential elements of the powered roof support hydraulic system is the safety valve. ... extraction of hard coal occurs mainly through underground mines' longwall systems [22 ...
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A proper routing
8 Min Read. Before retrofitting or modifying high-pressure hydraulic lines on longwall mining equipment, it is important to apply safe hydraulic hose fitting and mounting …
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Hydraulic Controls – Australia's Most Trusted Fluid Power …
Hydraulic Controls is committed to providing exceptional service in the design, manufacture and supply of fluid power systems. Our objectives include creating satisfied stakeholders and continually improving our management system. To that end, we have developed a custom framework to establish, maintain and achieve these objectives.
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Hauhinco Water Hydraulics
Hauhinco high-pressure stations for longwall hydraulics are premium, certified systems with all the necessary approvals. This also applies to the spraying stations for the supply of the shearer water sprays, coal plow operations and cooling systems of drive motors. Hauhinco systems guarantee the necessary safety and …
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Longwall mining demands safety and reliability in equipment
This system uses a range of data supplied from equipment used in the process of continuous longwall mining and uses it to calculate the changes in demand for hydraulic fluid before they occur.
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Analysis of the Pressure Increase in the Hydraulic …
to analyses the pressure increase in the safety valve during shock loading. The tests used a hydraulic cylinder (from the powered roof support) loaded using a freefalling mass. Such loading systems are commonly used for coal longwall shield testing and are availa-ble, for example, in Poland and the Czech Republic. The research concept and its ...
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Improving safety and productivity in coal mines
Around 90 per cent of Australia's underground coal production comes from longwall mining. Traditionally, a mechanical shearer cuts along the coal seam beneath a roof supported by hydraulic jacks, exposing miners to multiple risks. Increasing safety and productivity in longwall mining has been a long-term industry goal.
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Analysis of support by hydraulic props in a longwall working
This paper presents a study of the support system in an anthracite working situated in Feixolin (Northern Spain). The working is mined by the longwall method, caving being controlled by means of hydraulic props and wooden cribs. As the coal seam has an average thickness of 3.5 m and 30° slope, the workings do not meet Spanish regulations …
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Fluid Power Systems for Longwalls
The hydraulic networks that deliver emulsion from the tanks in the headgate to the last shield on the face also determine the overall efficiency of operations. by alcwyn elliott. With today's modern longwall mining systems, fluid distribution from the high-pressure pumps to the last shield on the face has to be efficient in all respects ...
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Longwall Hydraulics Awarded New Pump Station Contract
As well as the dedicated dust suppression, Longwall Hydraulics will also implement new designs on the pump cart to improve performance and efficiency in operation. New safety initiatives to reduce fluid injection potential. The pump station is designed to allow all pumps to be operated as both main Emulsion system and Hi Set …
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Measurement and analysis of the roof pressure on hydraulic …
The mining method employed is the longwall coal face, in which caving is controlled by means of individual hydraulic props.We first report the empirical formulas used to estimate the roof pressure ...
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Hydraulic Control Systems for Longwall Shield Supports
Abstract. Recent shield support developments demand a new approach to hydraulic control systems due to higher support loads, heavier supports and greater speed of operation demanded to cater for modern coal machines. The paper reviews system requirements and systems currently developed i.e.:-. Adjacent support control.
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Guideline for fluid power safety systems at mines
5.1. General. This section applies to the commissioning of the fluid systems at mines, including pumps, hoses, valves, gauges, accumulators, filters and actuators. Fluid power systems should be commissioned in accordance with the designer's documentation and ISO 4413, ISO 4414 and AS 4041 as applicable.
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Hose Safety and Reliability in Mining | Power & Motion
The movable hydraulic shields in longwall mines advance with the shearer throughout the mining process, enabling increased productivity as well as improved …
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Roof Supports (mining) Selection Guide: Types, Features
These are sophisticated hydraulic systems used in high-production environments like longwall operations. They offer high load-bearing capacity and can be automatically or remotely controlled to advance with the mining operation. ... robust roof supports like steel sets or rock bolts are commonly used to prevent cave-ins and ensure safety. Coal ...
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ACARP Abstract
a) Hydraulic hose assembly duty - there is a need to understand loading severity under various operating conditions. It was proposed that representative samples (i.e. 4 - 6 weeks) of in-service pressure history data are established for two longwall system designs; namely, Joy and Bucyrus/ longwall systems.
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Development of a Hydraulic System for the …
The pressure drop in the hydraulic system after expanding the sections in the longwall excavation causes uneven support of the roof along the length of the wall. This affects the improper cooperation of the …
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Performance and Safety Considerations of Hydraulic …
The manufacturer of the oil can provide accurate data on the bulk modulus. A value of 320,000 psi is recommended in the absence of manufacturer data. This value can also be used for water-oil emulsions such as those used in longwall shields. K„ = stiffness of stage n, lbs/in. = area of stage n, in2.
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8.4.2c Longwall Mining | GEOG 000
Longwall Mining of Coal. Longwall mining of coal is a high production and high productivity method, employing sophisticated electrical, mechanical, and hydraulic systems, as well as computer-based monitoring and control systems. Most modern (coal) longwall faces are semi-automated. It is noteworthy that longwall operations in trona …
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