OSBL
OSBL is an abbreviation of Outside Side Battery Limits.
OSBL refers to systems (equipment pieces and associated components) that support several units. Typical OSBL equipment includes cooling towers, water treatment facilities, tanks farms, etc.
OS&Y
OS&Y is an abbreviation of Outside Screw &
Yoke.
A valve design in which the threaded portion of the stem is outside the pressure boundary of the valve. The valve bonnet has a Yoke, which holds a nut through which the rotating stem rises as the valve is opened. The stem part inside the valve is smooth and is sealed so that stem threads are isolated from the flow medium.
