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Double-Deck Coach Product

Overview

A double-deck coach is a hauled (unpowered) passenger vehicle that stacks two seating decks inside one carbody to raise capacity without lengthening the train. It carries no traction equipment of its own — a locomotive or a powered end car moves it — so its design problem is fitting two floors, a staircase, doors and a toilet inside the fixed loading gauge while keeping the centre of gravity low enough for stable running. The answer is a dropped centre floor: the underframe sags between the bogies so the lower saloon sits close to rail level, the upper saloon rides above it, and short stairs at each end connect the two. The result carries roughly twice the seats of a single-deck coach over the same length of platform.

How it works

The vehicle is built around the Bilevel Carbody Shell, a welded steel monocoque whose deep fishbelly underframe drops the lower-deck floor while the upper-deck floor and roof close the shell above. Passengers move between levels on the Internal Staircase at each end. The body rests on two Railway Bogie trailer running-gear units, and braking comes from a Friction Brake Unit on every axle, each clamping a Brake Disc (rotor) with a pneumatic cylinder fed from the train brake pipe.

Boarding is through wide Entrance Door entrances on the lower deck, each worked by a motorised operator. Both decks are filled with Seat Assembly passenger seating and served by roof HVAC Roof Unit climate units, one per deck. A Toilet Module provides an accessible vacuum WC with its own water and retention tanks. The Lighting & PA System system runs LED saloon lighting, announcement speakers and passenger-information displays.

At each end a Coupler with draft gear handles coupling loads, and a Gangway Connection with bellows and a bridge plate lets passengers walk between coaches. Large Side Window panes glaze both decks. The Coach Control Box ties the doors, brakes, HVAC and lighting to the train control bus through its boards and connectors, so the coach responds to commands from the driving end.

Build & assembly graph

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Bill of materials

13 top-level lines · 69 rows shown · 1,193 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Bilevel Carbody Shell 5 parts ddc-carbody-shell 1 6 assembly
1.1 Fishbelly Underframe ddc-underframe 1 part
1.2 Lower Deck Floor ddc-lower-deck-floor 1 part
1.3 Upper Deck Floor ddc-upper-deck-floor 1 part
1.4 Sidewall Panel ddc-sidewall 2 part
1.5 Roof Shell ddc-roof-shell 1 part
2 Internal Staircase 3 parts ddc-staircase 2 15 assembly
2.1 Stair Frame ddc-stair-frame 2 part
2.2 Stair Tread ddc-stair-tread 12× 24 part
2.3 Handrail ddc-handrail 4 part
3 Railway Bogie 5 parts bogie 2 27 assembly
3.1 Bogie Frame bogie-frame 2 part
3.2 Wheelset 2 parts bogie-wheelset 4 3 assembly
3.2.1 Wheelset Axle bogie-axle 4 part
3.2.2 Rail Wheel bogie-wheel 8 part
3.3 Axlebox Bearing 2 parts bogie-axle-bearing 8 3 assembly
3.3.1 Ball Bearing ball-bearing 8 part
3.3.2 Oil Seal oil-seal 16 part
3.4 Coil Spring coil-spring 8 part
3.5 Air Spring bogie-air-spring 8 part
4 Friction Brake Unit 3 parts ddc-friction-brake 8 3 assembly
4.1 Brake Disc (rotor) brake-disc 8 part
4.2 Brake Cylinder ddc-brake-cylinder 8 part
4.3 O-Ring Set oring-set 8 part
5 Seat Assembly 5 parts seat-assembly 110× 110 7 assembly
5.1 Seat Frame seat-frame 110 part
5.2 Seat Foam seat-foam 220 part
5.3 Seat Cover seat-cover 110 part
5.4 Seat Motor seat-motor 220 part
5.5 Seat Heater Mat seat-heater 110 part
6 Entrance Door 2 parts ddc-door 2 27 assembly
6.1 Door Leaf ddc-door-leaf 4 part
6.2 Door Operator 4 parts ddc-door-operator 2 25 assembly
6.2.1 Stator Assembly 3 parts + deeper › stator-assembly 2 3 assembly
6.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 2 19 assembly
6.2.3 Microcontroller mcu 2 part
6.2.4 Connector connector 4 part
7 HVAC Roof Unit 3 parts ddc-hvac-unit 2 51 assembly
7.1 HVAC Compressor ddc-hvac-compressor 2 part
7.2 Heating Element heating-element 4 part
7.3 Supply Blower 3 parts ddc-hvac-blower 4 24 assembly
7.3.1 Stator Assembly 3 parts + deeper › stator-assembly 4 3 assembly
7.3.2 Rotor Assembly 4 parts + deeper › rotor-assembly 4 19 assembly
7.3.3 Ball Bearing ball-bearing 8 part
8 Toilet Module 4 parts ddc-toilet-module 1 27 assembly
8.1 Toilet Bowl ddc-toilet-bowl 1 part
8.2 Vacuum Unit 3 parts ddc-vacuum-unit 1 24 assembly
8.2.1 Stator Assembly 3 parts + deeper › stator-assembly 1 3 assembly
8.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 1 19 assembly
8.2.3 Ball Bearing ball-bearing 2 part
8.3 Fresh Water Tank ddc-water-tank 1 part
8.4 Waste Retention Tank ddc-waste-tank 1 part
9 Lighting & PA System 4 parts ddc-lighting-pa 1 65 assembly
9.1 LED Light Strip ddc-led-light 48× 48 part
9.2 PA Speaker ddc-speaker 12× 12 part
9.3 LCD Panel lcd-panel 4 part
9.4 Bare PCB pcb-bare 1 part
10 Coupler 2 parts ddc-coupler 2 2 assembly
10.1 Coupler Head ddc-coupler-head 2 part
10.2 Draft Gear ddc-draft-gear 2 part
11 Gangway Connection 2 parts ddc-gangway 2 2 assembly
11.1 Gangway Bellows ddc-gangway-bellows 2 part
11.2 Bridge Plate ddc-gangway-bridge 2 part
12 Side Window ddc-window 40× 40 part
13 Coach Control Box 4 parts ddc-control-box 1 13 assembly
13.1 Bare PCB pcb-bare 2 part
13.2 Microcontroller mcu 2 part
13.3 Connector connector 8 part
13.4 Wire Bundle wire-bundle 1 part

Sourcing — likely vendors

Companies that make this · indicative price $500k–$60M · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
🇨🇳CRRC
crrcgc.cc ↗
Beijing, CN Rolling stock & rail systems made to order 40–72 wks
🇫🇷Alstom
alstom.com ↗
Saint-Ouen, FR Rail rolling stock made to order 40–72 wks
mobility.siemens.com ↗ Munich, DE Rail systems made to order 40–72 wks
🇨🇭Stadler Rail
stadlerrail.com ↗
Bussnang, CH Rail rolling stock made to order 40–72 wks
🇺🇸Wabtec
wabteccorp.com ↗
Pittsburgh, US Rail equipment made to order 40–72 wks

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