SECURITY ARRANGEMENTS FOR TESTING THE CONVERSION OF A COAL STOCK OF A CYLINDER CONTRACT IN A COAL/CYLINDER AGGREGATE

摘要

A packing arrangement for packing of the passage of a piston rod 3 through a cylinder cover 2 in a piston- cylinder aggregate controlled by means of a pressurised fluid, comprises a packing 10 arranged in the cylinder cover and surrounding the piston rod, and a scraper ring 11 arranged at the outside of the cylinder cover and surrounding the piston rod. An annular groove 6 surrounding the piston rod 3 is formed in the cylinder cover 2 between the packing 10 and the scraper ring 11. The annular groove 6 is connected to a source 15 of vacuum which is adapted to maintain a certain defined normal pressure in the groove. A supervising means 17 is arranged to supervise the pressure in the groove 6 in order to indicate the condition if the pressure therein deviates from said normal pressure. IMAGE