The NDJ3 "Great Wall", previously labeled the "Harmony Great Wall" is the only higher-speed diesel multiple unit that is still operating in China. It was first designed to be used for passenger transport in the 2008 Olympics, and has become a mature technology platform with export orders to Nigeria despite initial flaws related to overheating of electrical cables in the power car.
| NDJ3 | |
|---|---|
 A NDJ3 approaching Qinglongqiao railway station | |
 the buffet car, fitted with panoramic windows | |
| Built at | CRRC Nanjing Puzhen CRRC Qishuyan |
| Entered service | 2008 |
| Number built | 9 |
| Number in service | 9 |
| Formation | M-T-T-T-T-T-T-T-M (China Railway) M-T-T-T-T-T-T-T-T-M (Nigerian Railway) |
| Operators | Beijing Suburban Railway Nigerian Railway Corporation |
| Specifications | |
| Train length | 220.5 m (723 ft 5 in) |
| Width | 3.105 m (10 ft 2.2 in) |
| Height | 4.433 m (14 ft 6.5 in) |
| Wheel diameter | 1.05 m (41 in)(power car, new) 970 mm (38 in) (trailer, new) |
| Maximum speed | 160 km/h (99 mph) |
| Axle load | 21 tons |
| Traction system | eight 530 kW |
| Prime mover(s) | two 12V280ZJ |
| Engine type | diesel |
| Traction motors | ZD106 |
| Power output | 3530 kW |
| Tractive effort | 4240 kW |
| Transmission | AC–DC |
| Acceleration | 1.368 km/(h⋅s) (0.850 mph/s) (starting) |
| AAR wheel arrangement | A1A-A1A |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in) |
Description
editTo fulfil the need for passenger transport between Beijing and Badaling during the 2008 Summer Olympics,[1] the Ministry of Railways ordered four NDJ3 DMU trains,[2] with the numbering NDJ3 0001-0004. All of them are with Beijing Bureau, Beijing sector Nanko depot, operating on Line S2 between Beijing North station and Badaling station via Yanqing station, with a later addition of another service from Beijing North to Shacheng station. These sets was the first diesel multiple units designed in China with the ability to negotiate ≥33‰ gradient and a curve of 180 m (590 ft 7 in), optimised for the steeper gradient of the S2 line, although this gearing for steeper lines also reduced the maximum speed from 180 to 160 km/h (112 to 99 mph), although they could be easily geared for higher speeds.[2]
The NDJ3 is developed from the NZJ1 "Xinshuguang" with a similar 2M7T layout where motor cars are diesel locomotives located on either end in a push–pull configuration, while also drawing from the experience of DF11 and DF11G locomotives.[2] The Qishuyan designed locomotives are fitted with a diesel-electric drive, generating AC which is then converted to DC for the traction motors. The main generator is supplemented by an auxiliary generator, which provides power to the passenger cabins. The Nanjing Puzhen designed passenger carriages are based on the 25T carriage while the exterior paint draws inspiration from the Harmony trains.[3] The passenger carriages have wide doors, extra large sightseeing windows, rotatable seating, disabled toilets and other passenger amenities designed for increased passenger comfort.
Flaws
editWhile running the S2 which has steep gradients, a burning smell was often noticed coming from the resistors that dissipate energy from braking. This was found to be the fault of cable 13, which heated up significantly in use. It was due to the design where the cable carries the power for both the Eddy current brake and the magnetic excitation for the 4th traction motor. The high temperatures poses a serious risk to safety, as it would degrad the cable faster, leading to a higher risk of fire, but also the risk of the brakes failing if the current is not supplied. At a speed of 28 km/h (17 mph) with the control lever on level 8 braking, the current exceeds the design limit by 1.72 times, and at around 33 km/h (21 mph) with 634 amps for the motor and 623 amps for the brake, the cable heats up to 55.4 °C (131.7 °F). To rectify this flaw, the cables for traction motor 4 were separated into separate cables for braking and motor power.[4] Nonetheless, it has not had any serious accidents, and the set was awarded first place in the 2009 Railway Technology prize.[5]
Service history
editChina
editThis train was put into operation on 6 August 2008 on Line S2 of the BCR. Although it carried the name "Harmony Great Wall" (Chinese: 和谐长城号),[6][2] it does not actually belong to the Harmony series of trains. During their service, they have also occasionally been used on other lines.[3]
At the end of 2017, Beijing bought two more sets for Huairou–Miyun line.[7][8] These sets, numbered NDJ3 0005-0007 have only second class seating and do not have a buffet car, significantly increasing the seating capacity. Line S2 was also supposed to receive another three sets, but they were never delivered for unknown reasons.[3]
From October 2019 onwards, the "Harmony" (Hexie) logos were gradually removed from the sets. These sets then carried only the "Great Wall" (Changchen) logos at the front.
Nigeria
editIn 2019, the Nigerian Railway Corporation ordered two sets, as part of the construction of standard gauge railways in the country, in an order with six DF11G, nine DF8 and two DF7 locomotives. In Nigerian service, the sets are classed as CDD5E1. These sets differ with a lower speed at 150 km/h (93 mph), USB charging and have an additional trailer with wheelchair parking, compared to the second series of NDJ3 delivered to Beijing. These sets commenced service with the Lagos-Ibadan railway on 7 December 2020.[9]
Set composition
editBeijing Suburban Railway
edit| Numbering | NDJ3 0001/2/3/4A/B | 1 | 2 | 3 | 4 | 5 | 6 | 7 | NDJ3 0001/2/3/4B/A |
|---|---|---|---|---|---|---|---|---|---|
| Car type | motor car | RZ1 25DT
first class seat |
CA 25DT
buffet car (bar layout) |
RZ2 25DT
second class seat |
motor car | ||||
| Traction | A1A-A1A | / | A1A-A1A | ||||||
| Wheel
configuration |
●〇● ●〇● | 〇〇 〇〇 | ●〇● ●〇● | ||||||
| Seats | / | 64 | 60 | 64 | 32 | 74 | 70 | 74 | / |
| Numbering | NDJ3 0005/6/7A/B | 1 | 2 | 3 | 4 | 5 | 6 | 7 | NDJ3 0005/6/7B/A |
|---|---|---|---|---|---|---|---|---|---|
| Car
type |
motor car | RZ2 25DT
second class seat |
motor car | ||||||
| Traction | A1A-A1A | / | A1A-A1A | ||||||
| Wheel
configuration |
●〇● ●〇● | 〇〇 〇〇 | ●〇● ●〇● | ||||||
| Seats | / | 114 | / | ||||||
See also
editReferences
edit- ^ "New Lagos-Ibadan Trains And Their Specs". Africa Today News. 2019-10-18. Retrieved 2021-11-17.
- ^ a b c d 方, 皎波; 王, 龙; 臧, 坚东 (July 2014). "NDJ_3型"和谐长城"号内燃动车". 铁道机车与动车. 485: 27–29.
- ^ a b c "NDJ3动车组 - 动车组列车 - 中国动车组". www.china-emu.cn. Retrieved 2021-11-16.
- ^ 闫, 克磊; 耿, 继武; 石, 万顺; 侯, 晓燕 (November 2011). "NDJ_3型动车组13号大线高温发热解决措施". 铁道机车与动车. 525: 34–35.
- ^ "NDJ3型准高速内燃动车_产品中心_机车新造_内燃动车组_南车戚墅堰机车有限公司". www.crrcgc.cc. Retrieved 2021-11-18.
- ^ "刘志军检查即将投入运营的北京至延庆市郊铁路". www.gov.cn. Retrieved 2021-11-15.
- ^ 常州市政府 (2017-07-29). "中车戚机公司研制新型内燃机车". 常州发布. Archived from the original on 2017-07-30. Retrieved 2017-07-30.
- ^ "NDJ3型内燃动车组交付 将投入在北京市郊铁路怀柔—密云线". www.sohu.com. Retrieved 2021-11-18.
- ^ "NDJ3N动车组 - 动车组列车 - 中国动车组". www.china-emu.cn. Retrieved 2021-11-16.
