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OIL MIST LUBRICATION-DRY SUMP
A method for lubricating anti-friction bearings which utilizes oil dispersed on an air stream. The mist is exhausted from the bearing housing so as not to permit oil to accumulate.
OIL MIST LUBRICATION-WET SUMP
Similar to Oil Mist Lubrication – Dry Sump, except that a pool of oil is developed in the bearing chamber. This oil pool will continue to supply oil to the bearing in the event that the oil mist is interrupted and is fed from a source outside the bearing housing such as a constant level oiler.
OPEN BEARING
A ball bearing that does not have a shield, seal or guard on either of the two sides of the bearing casing.
OPEN EXTERNALLY-VENTILATED MACHINE
A machine that is ventilated with external air by means of a separate motor-driven blower mounted on the machine enclosure.
OPEN PIPE-VENTILATED MACHINE
An open machine except for openings for the admission of ventilating air is so arranged that inlet ducts or pipes can be connected to them. Air may be circulated by means integral with a machine or by means external to and not a part of the machine. In the latter case, this machine is sometimes known as a separately- or force-ventilated machine.
OPEN (PROTECTED) MOTOR
A motor having ventilating openings which permit passage of external cooling air over and around the windings. The term “open machine”, when applied to large apparatus without qualification, designates a machine having no restriction to ventilation other than that necessitated by mechanical construction.