FIAT BOGIE IN LHB COACH

 3.4 FIAT BOGIE. 

The LHB coaches are provided with the FIAT bogies to run at a speed of 160 KMPH. 

Limitations of ICF all Coil Bogie 

• The longitudinal and lateral movements of the wheels cannot be controlled independently as generally required for Highspeed bogies. 
• Since there is vertical space constraint between the top and bottom bolster, it is not possible to provide softer secondary suspension springs which are required for the high speed trains to control the dynamic movements of the bogie bolster and coach body. 
• Headstocks increase the yaw inertia of the bogie frame and thereby, influence the tendency for hunting. The wheelbase of ICF all coil bogie is 2896 mm. This large wheelbase affects curve negotiations and thereby increases wheel flange wear. 131 
• Since the brake forces are offered on the wheel tread by clasp brake, it could not give sufficient retardation during brake application which in turn increases the emergency braking distances. The life of the wheel is also reduced due to tread wear. 

3.4.1 FIAT BOGIE PARTS 

• Design obtained from M/S Alstom-LHB, Germany as part of LHB-TOT contract 
• Adapted at RCF for various coach variants 
• Fit to run up to 180 kmph 
• Superior ride quality 
• Bump stops in primary and secondary suspension 
• Miner pads in secondary suspension 
• Yaw, lateral and vertical dampers 
• Nested spring sets with 2 helical and one rubber spring in secondary 
• Less wear and tear

3.4.2 BOGIE FRAME 

• Solid welded frame -steel sheets (ST-52) and forged, steel cast parts to material GS20MN5V; DIN 17182 (weld able). 
• Two side frames connected by two cross beams -support brake units various brackets on frame. 
• The bogie frame rests on the primary suspension spring units and supports the vehicle body by means of a bolster beam. The bolster beam is connected to the bogie frame by secondary suspension. 

Primary suspension 

• Two coil springs, one vertical damper, articulated control arm, elastic joints connecting the axle bearing to the bogie frame 
• Better curve negotiation.