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The pressure transducer installed in the hydraulic system play an important role for the correct work of the powered roof support. Currently, in the free market economy there are many manufacturers offering a wide range of such products, however, it is often difficult to find a solution that would meet specific requirements, for example when selecting a pressure transducer for a powered roof support. It is difficult to find an ideal transducer that would meet all the requirements for the correct operation of the s...

Work safety in hard coal mines is implemented based on Geological and Mining Law. It imposes an obligation on the entrepreneur to identify hazards related to activities of the mine and to undertake actions aimed at preventing and removing these threats and hazards. The owner is required to assess the risk and propose solutions necessary to minimize it. These activities must cover all activities performed during the production process and the operation of all types of equipment, including mining machines. The most ...

An electrohydraulic control system as a part of powered roof support is required to be equipped with a safety valve. The aim of the valve is to protect the roof support against overloads that may damage hydraulic legs, and subsequently lead to loss of stability of the whole support unit. In order to select optimal operating parameters of the safety valve it is necessary to carry out tests in conditions similar to those in the mine. The tests should reflect the actual load condition of the support as much as possib...

A wireless system of continuous monitoring of pressure in a leg mounted in a powered roof support was designed in order to ensure the continuity of longwall coal mining process. Wireless multi-channel signal transmission in the longwall was applied for the first time. The extension of the power cell enabled maintenance-free use of the system and ensured comprehensive control of the support. The presented system monitors the pressure value in the spaces under the leg?s piston mounted in a powered roof support as we...

Introducing new technical solutions into practice is inseparably connected with a number of problems. In addition to obvious concerns about the quality, reliability and effectiveness of the solution, there are also social problems. They are related to distrust of employees regarding new solutions and is caused by a limited knowledge about the introduced product which is related to employees' concerns that such a product may disturb the existing state of balance. Therefore, in the case of introducing a new solution...

One of the fundamental problems in coal mining industry is inefficient use of machinery and equipment. It is therefore necessary to take measures to improve the situation. An innovative system to test components of mining machinery control hydraulics presented in the article may support the initiative. This system enables reliable and efficient testing of components of the control hydraulics. This has an essential and practical significance, since hydraulic systems are commonly applied by many industries, in parti...

One of the most significant elements of every machine operation is its control system. Proper design, construction and operation of the control system is the key factor for correct and efficient operation of a machine. This particularly applies to mining machinery operating in hazardous environments and exposed to loads which cannot be fully predicted. Such machines must be therefore characterized by high reliability, durability, readiness and safety. In order to fulfil all these requirements, a machine must be eq...