Performance and Safety Considerations of Hydraulic Support Systems

摘要

Hydraulic cyclinders are used in several roof support systems, such as longwall shields and mobile roof supports, to provide critical ground control. Many state-of-the-art hydraulic support systems operate at pressures as high as 7,000 psi to provide the multi-stage cylinders can be intesified by a factor of 2 or 3 providing pressures of 20,000 psi or greater. This paper examines the basic operating principles of state-of-the-art hydraulic cylinders and discusses relative issues pertaining to (1)setting loads, (2) support stiffness, (3) yielding behavior, (4) errors in assessing support loading, and (5) hydraulic failure mechanisms and how to detect them.