Abstract: A self-contained closed-circuit oxygen-generating breathing appratus is provided with a partition wall disposed in such a manner as to oppose at least the lower portion of the inner surface of a breathing bag. The partition wall partitions the central portion and peripheral portion of the interior of the breathing bag along the inner surface of the breathing bag, and the space or gap between the partition wall and the inner surface of the breathing bag acts as a passage for oxygen-enriched gas discharged from the outlet of a canister of an oxygen-generating agent into the interior of the breathing bag. The oxygen-enriched gas can flow through the passage while kept in good contact with the inner surface of the breathing bag, and thus can be cooled to a temperature suitable for inhalation by the user.

Abstract: A thermoplastic lined plug valve is prepared using a plug having a nonlocking taper and a stem at the small end of the plug. The plug is seated initially by forcing the plug into the plug cavity, raising the temperature of the plug valve above the service temperature of the valve body lining until the valve body lining conforms to the valve plug. The valve is then cooled to a temperature below the service temperature of the body lining.

Abstract: A control arrangement for supplying pressure fluid through a supply conduit from a source of pressure fluid to at least two hydraulically operated consumer devices includes, for each of the consumer devices, a valve having a valve member movable axially between a neutral position preventing flow of pressure fluid to the respective consumer device and two working positions respectively connecting the consumer device to the source of pressure fluid or a return conduit. A throttle is located in the supply conduit between a first point of the latter from which a first branch conduit branches off to a first of the valves and a second point from which a second branch conduit branches off to the second of the valves. The arrangement includes further a control valve and a control circuit therefor, controllable at least by the valve member of one of the valves. In the neutral position of all valve members the supply conduit is connected with the return conduit to form therewith a neutral fluid circulation passage.