DOC AIRBUS | AMM A320FFAN FRAME ASSEMBLY - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The fan frame module provides front handling mounts and is the main forward support for mounting the engine to the aircraft. Its purpose is to support the fan, booster and high pressure compressor (HPC) rotors, and to provide ducting for primary and secondary airflows.
The fan frame module consists of the following major assemblies:
** ON A/C NOT FOR ALL The fan frame module provides front handling mounts and is the main forward support for mounting the engine to the aircraft. Its purpose is to support the fan, booster and high pressure compressor (HPC) rotors, and to provide ducting for primary and secondary airflows.
Fan Frame AssemblyThe fan frame module consists of the following major assemblies:
- Fan frame assembly.
- Fan Inlet Case assembly.
2. Fonctions
The Fan Frame and Fan Inlet Case perform the following primary functions:
The Fan Frame and Fan Inlet Case perform the following primary functions:
A. Fan Frame.
(1) An inlet airflow path to the core engine.
(2) A support for loads of the fan stator, fan rotor and fan reverser.
(3) Containment of accessory drive power take off gears (inlet gearbox) and radial drive shaft arrangement.
(4) A variable bypass bleed valve system.
(5) Housing for the oil pressure, scavenge, drain lines and venting/pressurisation/sealing system associated with the bearings and gears located in the engine forward sump.
B. Fan Inlet Case.
(1) Provides for attachment of the engine inlet cowl and the support and transmission of attachment loads from this point to the fan frame.
(2) Provides fan blade containment.
(3) Provides attachment points for acoustical panels, and fan OGV.
(4) Provides an abradable lining for fan blade tips.
A. Fan Frame Assembly
The fan frame assembly is a fabricated structural weldment made of concentric rings connected by radial struts. It consists of the basic fan frame structure and the fan inlet case assembly.
The fan frame assembly is a fabricated structural weldment made of concentric rings connected by radial struts. It consists of the basic fan frame structure and the fan inlet case assembly.
(1) The basic fan frame structure is made of steel alloy. It consists of a hub, mid box structure and outer casing interconnected through 4 thick and 8 thin radial struts.
(a) Structural strength for the fan frame is obtained from the 12 struts. The struts are hollow and provide passage for the following equipment :
1 No. 1 bearing vibration sensor cable (No. 4 strut).
2 N1 speed sensor and drain cavity (No. 6 strut).
3 Transfer gearbox (TGB) radial drive shaft and scavenge tube (No. 7 strut).
4 Forward sump oil supply tube (No. 10 strut).
(b) The hub front face supports the No. 1 and No. 2 bearing support. The rear face supports, from front to rear, the IGB and No. 3 bearing module and the rear stationary air/oil seal together with its pressurization air supply ring. The hub outer surface, which is also the inner wall of the primary airflow annulus, has orifices for bleed air requirements.
(c) The mid box structure is located radially between the primary and secondary airflows. It houses the 11 variable bleed valve (VBV) ballscrew actuators and the VBV master ballscrew actuator , and air scoops for the LPT active clearance control system (LPTACC). The front flange of the structure supports the rear outer flanges of the stage 5 booster vane assembly, and the fan OGV inner shroud. The structure rear flange supports the HPC forward case, the VBV hydraulic fuel gear motor and provides for engine mounting.
(d) The outercasing makes up the outer wall of the secondary airflow. Located on the outer surface of the casing are the 2 ground handling mounts and the TGB mounting pad. The fan inlet case mounts to the outer casing front flange, and the fan discharge duct mounts to the outer casing rear face.
(e) An adapter ring, with a V-groove, is bolted to the outer casing rear flange to adapt the outer cowl of the engine (fan) thrust reverser (Ref. AMM D/O 78-30-00-00).
4. Fan Inlet Case Assembly
The fan inlet case assembly is composed of the 2 parts which follows:
The fan inlet case assembly is composed of the 2 parts which follows:
- The upstream fan case
- The downstream fan case
The upstream fan case is a structural weldment made of alloy steel. The outer rear flange is bolted to the downstream fan case outer front flange.
The downstream fan case is made of aluminium. The outer rear flange is bolted to the outer front flange of the fan frame.
The outer surface of the fan inlet case assembly has flanges and ribs to provide additional strength to the case during engine operation. It also has 2 hoisting points for engine ground handling purposes (2 and 10 o'clock positions), 2 accessory gearbox (AGB) mounts and various other mounting provisions for engine equipment. The inner surface houses an abradable shroud located radially in line with the fan rotor blades, 6 fan forward acoustical panels, 6 fan mid acoustical panels, the fan OGV assembly and 12 aft acoustical panels. The engine air inlet cowl is attached to the front flange of the fan inlet case.
The fan outlet guide vanes (OGV) are made of composite material. The fan OGV inner shroud rear flange is bolted to the fan frame. Its forward outer surface contains 34 apertures to allow passage of the vane inner platforms and two borescope inspection ports. The fan splitter fairing is attached to the forward end of the fan OGV inner shroud. The fan OGV assembly has 34 twin vanes (or vane doublets). The vane inner platform are axially retained by the inner face of the fan (OGV) inner shroud. The vane outer platforms are bolted to the fan inlet case.