Lecture 16 - Light rail vehicles and Trams

Question 1

Classfication of Trammway vehicles acc. to BOStrab

Answer 1

Passenger vehicles: Traction Units, Trailer cars

Service vehicles

Question 2

Vehicle Classification according to floor level (reminder)

Answer 2

High floor vehicle (LRV): 600 < Floor heigh < 1000 mm
Semi-low floor vehicle (Trams & LRV): 350 < Fh < 600mm
Low floor vehicle (Tramway): Floor heigh < 350 mm
Boarding height < 300 mm

Question 3

Trailer cars characteristics

Answer 3

+ Flexible train composition
+ Simple retrofitting to low-floor technology
- No walk though between cars
- Reduced adhesion weight decreases starting capacity and gradeability

Question 4

High-floor and semi-low-floor vehicle concepts and draw them (figure 16.1, 16.2)

Answer 4

Concept 1: Two-axle car with rigidly mounted axles
Concept 2: Four-axle two boggie cars
Concept 3: Divided four-axle two bogies car
Concept 4a: Four axle two boggie cars plus semi-trailer with “floating” joint
Concept 5: Eight-axle, three car articulated unit with bogieless centre aprt
Concept 4b: Three car articulated unit with two boggies centre car plus two semi-trailers with flotant joints
Concept 6a: Two car single axle articulated unit with Jacobs bogie
Concept 6b: Three-car eight axle articulated unit with Jaobs bogies
Cocept 7: Three car six axle articulated unit with short centre car plus two semi-trailers with floating joints

Question 5

Requirements for Low-Floor vehicles

Answer 5

Boarding height < 300 mm
Low floor height < 350 mm
As few steps as possible
As many doors as possible in low floor area

Question 6

Implementation options for low-floor running gear

Answer 6

• Wheel pair and Drive
High-floor: wheelset
Semi-low-floor: small-diameter wheelset
Low-floor: independent wheels
• Less running gear longitudinal extension
Drawbacks: shorter distance between running gear units, more running gear units or higher wheel loads
• Minimize the pivoting option
• Reduced Number of Running Gears per Vehicle Lenght
Drawback: Higher wheel loads

Question 7

Low-Floor vehicles: Implementation measures

Answer 7

• Smaller or independent wheels
• Smaller motors
• Motors mounted at the sides
• Smaller running gear units
• Single-axle running gear
• Less running gear units
• Electric equipment of the roof

Question 8

Most important Low-Floor concepts with conventional running gears

Answer 8

N5,N6,N7 (=4b) Classic
N13 (=2b) Vehicle with centre double axle running gear
N10,14 (=4b) Multi-articulated vehicle
N16(=6b) Articulated vehicle with Jacob bogies

Question 9

Percentage distribution of the Sold Low-Floor Tram types btween 1989-2017

Answer 9

N10/14: 60% (66)
N5,6,7: 10% (11)
N13: 10% (8)
N16: 5% (3)

Question 10

Advantages and disadvantages of the most important low-floor concepts

Answer 10

N10/14:
+ 100% low floor
+ low clearance outline requirements
+ free interior design in the litters
+ large gangway width
- poor behaviour into and out of curved track
- moderate running behaviour on straight track

N5,6,7:
+ good running behaviour on straight track
+ good behaviour into and out of curved track
- < 100% low floor
• few restrictions for interior design
• medium clearance outline
-small gangway width

N13:
+100% low-floor
+good running behaviour on straight track
• moderate behaviour into and out of curve track
- high clearance outine requirements
- restricted interior design
- restricted gangway width

N16:
- <100% low floor design
• satisfiable running behaviour on straight track
+ good behaviour into and out of curved track
• medium clearance outline requirements
• few restrictions for interior design
+ large gangway width