The Indian locomotive class WAP-7 is a class of 25 kV AC electric locomotives that was developed in 1999 by

Chittaranjan Locomotive Works Chittaranjan Locomotive Works (CLW) is an electric locomotive manufacturer based in India. The works are located at Chittaranjan in the Asansol Sadar subdivision of West Bengal, with an ancillary unit in Dankuni. The main unit is 32 km f ...

(CLW) for

Indian Railways Indian Railways (IR) is a statutory body under the ownership of Ministry of Railways, Government of India that operates India's national railway system. It manages the fourth largest national railway system in the world by size, with a tot ...

. The model name stands for broad gauge (W), AC Current (A), Passenger traffic (P) engine, 7th generation (7). They entered service in 2000. A total of 1424 WAP-7 have been built, with more units being built at CLW,

Banaras Locomotive Works The Banaras Locomotive Works (BLW) (formerly Diesel Locomotive Works (DLW)) in Varanasi, India, is a production unit of Indian Railways. DLW stopped manufacturing diesel locomotives in March 2019 and was renamed BLW in Oct 2020. History Founde ...

(BLW) and

Patiala Locomotive Works Patiala Locomotive Works (PLW), (formerly Diesel-Loco Modernization Works (DLMW)), is located in Patiala in the Indian state of Punjab. It was set up in 1981 to extend the service life of diesel Locomotives of the Indian Railways and raise the ...

(PLW). The WAP-7 is one of the most successful locomotives of Indian Railways serving passenger trains for over 22 years. It is a passenger variant of the

WAG-9 The Indian locomotive class WAG-9 is a class of 25 kV AC electric locomotives that was developed in 1995 by ABB Group (ABB) for Indian Railways. The model name stands for broad gauge (W), AC Current (A), Goods traffic (G), 9th generation (9 ...

freight locomotive with a modified

gear ratio A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage. Gear teeth are designed to ensure the pitch circles of engaging gears roll on each other without slipping, providing a smooth transmission ...

to pull lighter loads at higher speeds. With an output of , it is the most powerful passenger locomotive in the

fleet, and the most numerous passenger locomotive in India. The WAP-7 is capable of hauling 24 coach trains at speeds .

History

It is now largely used by

Northern Railways The Northern Railway (NR) is one of the 19 Railway zones of India and the northernmost zone of the Indian Railways. It is headquartered at Baroda House in New Delhi. History Officially notified as a new railway zone on 14 April 1952, ...

(NR),

South Central Railways The South Central Railway (abbreviated SCR) is one of the 19 zones of Indian Railways. The jurisdiction of the zone is spread over the states of Telangana, Maharashtra, Karnataka, Andhra Pradesh. It has three divisions under its administrati ...

(SCR),

Central Railways Central Railway (abbreviated CR) is one of the 19 zones of Indian Railways. Its headquarters is in Mumbai at Chhatrapati Shivaji Maharaj Terminus. It has the distinction of operating the first passenger railway line in India, which opened from ...

(CR),

South East Central Railways South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþaz ...

(SECR), South Eastern Railways (SER), West Central Railways (WCR),

Eastern Railways The Eastern Railway (abbreviated ER) is among the 19 zones of the Indian Railways. Its headquarters is at Fairley Place, Kolkata and comprises four divisions: , , , and . Each division is headed by a Divisional Railway Manager (DRM). The name o ...

(ER),

Western Railways The Western Railway (abbreviated WR) is one of the 19 zones of Indian Railways and is among the busiest railway networks in India, headquartered at Mumbai, Maharashtra. The major railway routes of Indian Railways which come under Western Rail ...

(WR),

North Central Railways The North Central Railway (abbreviated NCR) is one of the 19 railway zones in India. The largest railway station in NCR is Kanpur Central. It is headquartered at Prayagraj and comprises three divisions: Allahabad division, Jhansi division, A ...

(NCR), South Western Railways (SWR), Southern Railways (SR), East Central Railways (ECR), East Coast Railways (ECoR),

North Eastern Railways The North Eastern Railway (abbreviated NER) is one of the 19 railway zones of Indian Railways in India. It is headquartered at Gorakhpur. Zonal Rail Training Institute (ZRTI) is established in district Ghazipur, Uttar Pradesh. North Eastern ...

(NER) etc among other zones. As of October 2021, all of which are fitted with H-type transition couplers which are compatible with both

screw coupling Buffers and chain couplers (also known as "buffers and screw", "screw", "screwlink", and "English" couplers) are the de facto UIC standard railway stock coupling used in the EU and UK, and on some surviving former colonial railways, such as in ...

and centre-buffer coupling. In February 2017,

built their first WAP 7 class locomotive. In 2019, a variant of the WAP-7, designated the WAP-7HS, was introduced for higher speeds. The WAP-7HS has a max speed of , and is capable of hauling a 24-car train at as opposed to the of the original. Indian Railways plans to use the WAP-7HS for Shatabdi, Rajdhani, and Duronto express trains. However, as of September 2022, it has not been confirmed if any others have been built, and the single completed WAP-7HS has stayed restricted to .

Head-on Generation (HOG)

A main feature of Majority locomotives of this class is that they eliminate the need to have separate End on Generation (EOG) sets or DG (Diesel Generator) sets for supplying power to the train resulting in significant savings on maintenance and running costs. This technology, called HOG or "Head On Generation", transfers electric power from the loco's

pantograph A pantograph (, from their original use for copying writing) is a mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen. If a line dr ...

to the coaches instead of EOG where a power car equipped with diesel generator capable of generating adequate power of 3-phase 50 Hz 415 V / 750 V AC (called '

head-end power In rail transport, head-end power (HEP), also known as electric train supply (ETS), is the electrical power distribution system on a passenger train. The power source, usually a locomotive (or a generator car) at the front or 'head' of a train, p ...

') is provided at either end of the train rake to supply power.

Locomotive sheds

References

External links

{{DEFAULTSORT:Indian Locomotive Class Wap-7 5 ft 6 in gauge locomotives 25 kV AC locomotives Co-Co locomotives Electric locomotives of India

History

Head-on Generation (HOG)

Locomotive sheds

See also

References

External links