The new KTNF8 three-segment tram was created through the reconstruction and modernization of the old four-axle two-segment CKD TATRA KT4 tram.
A central low-floor segment was integrated between the two original segments. This tram is intended for unidirectional operation. The vehicle is driven from one driver's compartment.
Central low-floor segment
The inserted central low-floor segment is of light steel construction and preserves the structural character of the original KT4 vehicle.
The body sections are connected with a combination of tried and tested RT6 tram joints, and a modification to the original KT4D under-frame. The lower ball hinge transfers load forces and is composed of a friction bearing with a spherical slip surface. The upper ball jinge is composed of a vertical connecting rod with two rubber-steel elements.
Standard bogies (mfg. by ALSTOM LBH GmbH), gauge 1200 mm, wheel diameter 410 mm. The vehicle body is connected to the bogies through a pivot and two slip surfaces on the sides. Two double-axle bogies can rotate through 12.5 degrees, and have 4 hydraulically controlled active disc brakes and 2 rail brakes. The primary suspension has rubber elements, and the secondary rubber rings with cylindrical coil springs.
The passenger compartment in the low-floor segment is connected to the KT4D area with stairs at either end. In light of the vehicle's design, the low-floor area is maximally utilized. The wheelchair section has folding seats in the side wall.
The door of the middle segment is in the centre of the vehicle. Under the door is a slide-out ramp controlled by the driver, which facilitates entry and exit for wheelchairs, baby carriages and persons of limited mobility.
Located on a vertical hand bar inside by the door is an integrated column that permits communication with the driver, control of the ramp, emergency brakes and emergency door opening.
The passenger compartment is heated with two electric heaters with fans, located below the seats.
The electrical systems are of type UA 37P, with TV14Z drive control. During startup, the TE036 A01 traction motors are run in low-loss mode by two pulse IGBT converters. During dynamic braking, the braking energy is fed back into the charging network. The driver's position has a display that shows information operational and fault conditions of the electrical system and instructions for further steps.
|Gauge||1000 mm / 1435 mm|
|Coupler to coupler length||26 554 mm|
|Vehicle width||2 180 mm|
|Vehicle height above track||3 560 mm|
|Floor level above track||900 / 360 mm|
|Traction bogie wheelbase||1 900 mm|
|New wheel diameter||700 mm|
|Weight||29 800 kg|
|Min. turning radius||16 m|
|No. of seats||60 (inc. 3 folding)|
|Standing room (5 pers./m2)||92|
|Standing room (8 pers./m2)||154|
|No. of traction motors||4|
|Traction motor output||54 kW|
|Maximum speed||65 km/h|
|Maximum acceleration||1,2 m/s2|
|Length||7 500 mm|
|Weight of central segment||9 300 kg|
|Bogie wheelbase||1 200 mm|
|Wheel diameter||410 mm|
|Floor level above track||360 mm|
|No. of seats||23 (inc. 3 folding)|
|Standing room (5 pers./m2)||25|
|Standing room (8 pers./m2)||42|