221series
Type index

Photos

Refurbised Kuha221


Refurbised Kuha221
with untifall plates


Background and overview
JR West was studying about next generation ideal trains delivered hereafter, after splitting of Japan National Railways. As the result, JR West developed 221 series suburban DC electric multiple unit (EMU) trains, realizing 2 car formations for the rural services to 12 car formations for the special rapid services, and having attractive appearance and passenger accommodation against competing private commuter rail operators. They entered to special rapid services and Yamatoji rapid services in 1989.

Car body
They have 2950mm wide body. Their body design incorporates lightweight shaped steel and pressed forming beam to realize a light weight body, employing weatherproof steel sheet (Steel Plate Atmospheric) for their body skin, and stainless plate and weatherproof steel sheet for their roof. Their roof features polyurethane waterproof coating for anti-corrosion improvement. They are equipped with three 1300mm wide double-leaf automatic sliding doors on each side of the vehicles. Door operating equipments, WTK112, are fitted above the door header of the sliding doors which can be operated manually by pushing the buttons fitted beside the door. Horizontal band of 4 set windows including 2 drop windows and door case windows having 1m height are fitted between the doors. The same seating capacity as 117 series is kept by reexamination of a switchboard installation position etc., regardless of increased doors for 117 series. Cab ends having a gangway at the front for underground railway use in the future are slanted at 15 degrees. Roller-binding train-type indicators and LED destination indicators are fitted on each side of their body. Two air conditioners, WAU701, rated at 18,000kcal/h/unit, and no ventilators are fitted on their roof. End cars are equipped with the automatic jumper coupler to ease rush-up operations.

Bogies
Motored bogies are WDT50H and trailer bogies are WTR235H, featuring bolster-less secondary air suspension, corn-shaped multilayered rubber spring journal supporting system, and the Z link traction device. These bogies adopt double collar sealed roller bearing and prepare to adopt the yaw dampers to ensure smooth ride characteristics even at 120km/h. Motored bogies employ the single tread brake device adopting automatic gap-adjusting unit, and trailer bogies employ both the single disk brake device and the single tread brake device.

6-car formation
Kumoha221 Moha221 Saha221 Moha220 Saha220 Kuha221
motored motored trailer motored trailer trailer
traction
system
compressor
aux. pwr

traction
system
aux. pwr
compressor WC

4-car formation
Kumoha221 Moha221 Saha221 Kuha221
motored motored trailer trailer
traction
system
compressor
aux. pwr

WC

2-car formation
Kumoha220 Kuha220
motored trailer
traction
system
aux. pwr
WC
compressor


Traction unit and ancillary equipments
221 series can be made 2-car, 4-car, and 6-car formations, since 221 series adopt married pair unit system as 211 series consisting of motored end car, class kumoha221, and motored intermediate car, class moha221, and the single unit system as 213 series, consisting of and motored end car, class kumoha220 and motored intermediate car, class moha220. Kumoha221 vehicles are equipped with the traction system, WCS57B, which controls eight silent series-wound brushed DC traction motors, WMT61S with a power output of 120kW, and Moha220 and Kumoha220 are equipped with the traction system, WCS59C, which controls 4 silent series-wound brushed DC traction motors, WMT64S with a power output of 120kW. These traction systems feature field added excitation control system. Motored end cars and Moha220 are equipped with cross-arm type current collector, WPS27. Class moha221 vehicles are equipped with an auxiliary power unit, WSC23, with a power output of 130kVA consisting of DC-DC converter featuring boosting chopper and 3-phase inverter, and a motor driven air compressor, WMH3093-WTC2000A under their floor. Class moha220 and kumoha220 vehicles cannot be equipped with a motor driven air compressor since the traction container and an auxiliary power supply are fitted under the floor and the space under the floor is insufficient. So, class saha220 and class kuha220 vehicles are equipped with a motor driven air compressor, MH3094-WTC1000C. 221 series incorporate the regenerative electric command braking system.

Accommodation
Seating accommodation consists of switchable transverse seating. A LED display for providing passenger information is fitted on the end wall. Straps were fitted throughout their body later, although straps were fitted at only the doorway at the beginning. Trailer end cars, Kuha221, are equipped with a Japanese style toilet.

8-car formation
Kumoha221 Moha221 Saha221 Moha220 Saha220 Moha220 Saha220 Kuha221
motored motored trailer motored trailer motored trailer trailer
traction
system
compressor
aux. pwr

traction
system
aux. pwr
compressor traction
system
aux. pwr
compressor WC

4-car formation
Kumoha220 Saha220 Moha220 Kuha220
motored trailer motored trailer
traction
controller
aux. pwr
compressor traction
controller
aux. pwr
WC
compressor

Operations
221 series started 120km/h operation after 117 series were replaced with 221 series completely in 1991. Furthermore, 221 series used on special rapid services were changed into eight-car formation or four-car formation in 1991, since passengers increased and transport capacity had been insufficient in six-car formation. Special rapid services were operated with eight-car formation or 2 four-car formations in pairs.
However, since 223-1000 series and 223-2000 series were delivered as the next generation suburban trains, 221 series gradually withdrew from special rapid services and 221 series began to be used on rapid services of JR Takarazuka, Nara, and Hanwa lines. Since JR west didn't have sufficient 4-car sets at that time, class moha220 and class saha220 included in six-car sets were transplanted to 2-car sets consisting of class kumoha220 and kuha220 in order to make additional 4-car sets.

Modification and refurbishment
From 2012, a refurbishment programme was commenced on 221 series. A LED destination indicator screen was fitted above the windscreen of the cab. High-Intensity discharge (HID) headlights and auxiliary headlights were employed. Flip-up seating next to the doorways were introduced in order to make doorways wider. Trailer end cars are equipped with a universal access toilet, and all end cars are equipped with a wheelchair space.
The prominent anti-fall plates on the front ends started to be fitted from 2015.

Latest operation status
221 series are now used on the rapid services of JR Kobe, JR Kyoto, Yamatoji, Nara, and Wakayama lines, and ordinary services of Biwako, San-in, Kosei, Kusatsu, Sakurai lines.
Technical Data
Items Data
Supply Voltage 1500VDC
Service speed, etc. Acceleration: 2.5km/h/s Deceleration: 3.5km/h/s Service speed: 120km/h
Length 19500mm
Width 2950mm
Height 4140mm
Bogie WDT50H(motored), WTR235H(trailer)
Collector WPS27 (cross-arm)
Traction motor WMT61S(120kW, 375V), WMT64S(120kW, 750V)
Gear ratio 5.19
Traction system Field added excitation control: WCS57B, WCS59C
Air conditioner WAU701 (18000kcal/h×2)
Designed by JR West