Swing check valves can be installed in both horizontal and vertical position. These valves are typically used in sizes 2 inches and over. The disk is suspended from the body by means of a hinge pin and seals against the seat which is integral with the body. Swing Check Valves are available in straight body design and y-pattern design.
Types of Check ValvesĬheck valves are available in the following designs: This is also called Non return Valve (NRV). Consequently, the oil coolers are the only means of dissipating the oil heat.Check valve is used to stop back flow in a piping system. Second, the large turbofan engines normally require a greater number of bearings, which means that more heat is transferred to the oil. First, air cooling of bearings by using compressor bleed-air is not sufficient to cool the turbine bearing cavities because of the heat present in area of the turbine bearings. Dry- sump lubrication systems require coolers for several reasons. This cooler may be air-cooled or fuel-cooled and many engines use both. An air oil cooler is usually included in a dry-sump oil system. It is similar in construction and operation to the air-cooled cooler used on reciprocating engines. The air-cooled oil cooler is normally installed at the forward end of the engine. Air oil coolers are used in the lubricating systems of some turbine engines to reduce the temperature of the oil to a degree suitable for recirculation through the system. Two basic types of oil coolers in general use are the air-cooled and the fuel-cooled. This vent equalizes pressure around the bearing surface so that the lower pressure at the first compressor stage does not cause oil to be forced past the bearing rear oil seal into the compressor.
A vent that leads directly to the bearing compartment may be used in some engines. Some breathers may have a baffle to prevent oil leakage during flight maneuvers. The screened breathers are usually located in the front center of the accessory case to prevent oil leakage through the breather when the aircraft is in unusual flight attitudes. If in enough quantity, oil leakage could cause burning and seal and bearing malfunction. Otherwise, the pressure buildup within the accessory case would stop the flow of oil draining from the bearing, forcing this oil past the bearing oil seals and into the compressor housing. The scavenged oil carries air into the accessory case and this air must be vented. In the accessory case, the vent (or breather) is a screen-protected opening that allows accumulated air pressure within the accessory case to escape to the atmosphere. The signal is sent to the FADEC/EICAS computer and is displayed on the lower EICAS display. Oil temperature can be sensed at one or more points in the engine’s oil flow path. A message is sent to the display in the upper EICAS display in the flight deck as can be seen in Figure 10. The differential oil pressure switch alerts the flight crew of an impending oil filter bypass because of a clogged filter. The low oil pressure switch alerts the crew if the oil pressure falls below a certain pressure during engine operation. The tank quantity transmitter information is sent to the EICAS computers.
WATERGEMS TANKS HAS CHECK VALVE FULL
An electronic sensor is placed to send a signal to the Full Authority Digital Engine Control (FADEC) control unit and through the Engine Indicating and Crew Alerting System (EICAS) computers, and on to the displays in the flight deck. The oil pressure transmitter connection is located in the pressure line between the pump and the various points of lubrication. The oil pressure gauge measures the pressure of the lubricant as it leaves the pump and enters the pressure system. Gauge connection provisions are incorporated in the oil system for oil pressure, oil quantity, low oil pressure, oil filter differential pressure switch, and oil temperature.
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