Indian locomotive class WDG-3A

WDG-3A
Katni based WDG-3A at Bangarpet Jn.
Type and origin Power type Diesel Builder BLW, Diesel Loco Modernisation Works Model ALCO 251C/ALCO DL560C variant Build date 1994–2015 Total produced 1,998 Rebuilder Diesel Loco Modernisation Works, Patiala
Specifications Configuration: ​  • UIC Co-Co Gauge 1,676 mm (5 ft 6 in) Bogies High adhesion Fabricated bogies Wheel diameter 1,092 mm (3 ft 7 in) Wheelbase 12.834 m (42 ft 1+1⁄4 in) Length 17.85 m (58 ft 6+3⁄4 in) Width 3.016 m (9 ft 10+3⁄4 in) Height 4.162 m (13 ft 7+7⁄8 in) Axle load 23,500 kg (51,800 lb) Loco weight 127 t (125 long tons; 140 short tons) Fuel type Diesel Fuel capacity 6,000 L (1,300 imp gal; 1,600 US gal) Prime mover ALCO 251-C RPM range 400–1050 RPM Engine type V16 Diesel engine Aspiration ABB VTC304-15 or Napier NA 295 IR turbocharger Traction motors BHEL TA 10102 CW (new), BHEL TG 10931 AZ(old) Cylinders 16 Cylinder size 228 mm × 266 mm (8.98 in × 10.47 in) bore x stroke Transmission Diesel electric MU working 2 Loco brake Air dynamic brake Train brakes Air, Vacuum and Dual
Performance figures Maximum speed 105 km/h (65 mph) Power output WDG-3A: 3,100 hp (2,300 kW) Tractive effort 37.90 t (37 long tons; 42 short tons) Factor of adh. 0.33
Career Operators Indian Railways Numbers 14501-14999, Newer 13000-13665 Nicknames Shakti, Prabal, Jai Jawan Locale throughout Indian Railways First run 1994 Retired Early 2020s–present Preserved 1 Disposition In service

The Indian locomotive class WDG-3A is a class of diesel–electric locomotive that was developed in 1994 by Banaras Locomotive Works (BLW),Varanasi for Indian Railways. The model name stands for broad-gauge (W), Diesel (D), Goods traffic (G) engine, 3,100 hp (3A) locomotive. They entered service on 18 July 1995. A total of 1,164 WDG-3A units were built between 1994 and 2015 at BLW, Varanasi with a few units being produced by Diesel Loco Modernisation Works (DLMW) and Parel Workshop.

It is the dedicated freight version of the highly successful WDM-2 and shares the same engine and horsepower rating with WDM-3A. It is considered to be a successful locomotive class with high reliability and few maintenance problems. Due to the introduction of more modern types of locomotives like WDG-4 and electrification, a significant number of locos have been withdrawn, condemned and scrapped. Yet a good number of examples are active on the mainline and for departmental services.

As of March 2026, 375 locomotives still retain "operational status" on the mainline as WDG-3A, with a few examples having been converted to WAGC-3 or WAG-10.

History

The first units of this class was delivered on July 18, 1995, under the name of WDG-2. The class was manufactured till end of 2015. All the older locomotives built by DLW had regular WDM-2 type square short hood profile and control stand position and the locomotives are rated at 3,100 HP.

From 2009 onward, they are equipped with Daulat Ram DBR, microprocessor control and an Auxiliary Power Unit (APU) in the short hood thus they bear external resemblance to the WDM-3D class. The WDG-3A has a higher tractive effort (7.5 t more) and axle load (1.7 t) compared to the WDM3A despite having the same engine and horsepower rating. Many units of this class has been named "Shakti" and can easily be recognized by their orange livery with cream stripe and lightning bolts. Besides Indian Railways, WDG-3A are being use by private companies for industrial uses, thermal power plants, port trusts, etc.

Production was stopped in 2015 when advanced locomotives like the WDG-4D were built, thus rendering the ALCO platform obsolete. Two WDG-4s can haul more goods than three WDG-3A combined. Meanwhile, Diesel Loco Works in Varanasi rebuilt few of the existing locomotives that had reached midlife into a purely electric twin section 10,000 hp (7,457 kW) locomotive, classifying them as the WAG-C3/WAG-10.

Sub Classes

WDG-3B

They were an experimental technical variant of the WDG3A with an upgraded ALCO engine to output 3,200 hp, though it was unsuccessful, and all units were reverted to normal WDG-3A. One of the locomotives of this class was numbered #14796.

WDG-3C

Another experimental class, but this time rated at 3300 hp. Only one unit (#14962) was produced and was painted in a unique "Dark Rose/Cheetah" livery. This loco was derated to 2,600 hp, but is still with the Katni diesel locomotive shed. This class was unsuccessful as well.

WDG-3D

Freight version of the WDM-3D. Only one (#13301) unit was marked with this marking. It may possibly be rated at 3400 hp. Now it has been derated to 2600 hp with WDG-3A class markings and homed at the Vatva Loco Shed.

Train Services

this diesel pull 90% goods trains and 10% passenger trains

• Karnataka Express (ICF rake)
• Udyan Express (LHB rake)
• Suvidha Express (LHB rake)
• Garib Rath Express (ICF rake)
• Sethu Express (ICF rake)
• Tebhaga Express (ICF rake)
• Golden Chariot (LHB rake)
• Palace on Wheels (LHB rake)
• Indore-Yesvantpur Express (LHB rake)
• Pothigai Express (both LHB and ICF rakes)
• Vivek Express (both LHB and ICF rakes)
• Boat Mail Express aka Rameswaram Express (ICF rake)
• Uttar Banga Express (ICF rake)

Locomotive sheds

Zone	Name	Shed Code	Quantity
Central Railway	Pune	PADX	15
	Kalyan	KYDX	8
	Kurla	CLAD	25
Eastern Railway	Andal	UDLD	4
	Jamalpur	JMPD	40
East Central Railway	Pt. Deendayal Upadhyaya	DDUX	9
	Samastipur	SPJD	17
East Coast Railway	Visakhapatnam	WATD	1
Northern Railway	Ludhiana	LDHD	48
	Lucknow	AMVD	25
	Tughlakabad	TKDD	10
North Central Railway	Jhansi	JHSD	18
North Eastern Railway	Izzatnagar	IZND	1
North Western Railway	Abu Road	ABRD	9
Southern Railway	Ernakulam	ERSX	7
	Golden Rock	GOCD	8
	Tondiarpet	TNPD	9
South Central Railway	Moula Ali	MLYD	7
South Coast Railway	Guntakal	GTLD	2
South Eastern Railway	Bondamunda	BNDX	9
South East Central Railway	Raipur	RPDX	34
South Western Railway	Krishnarajapuram	KJMD	8
Western Railway	Ratlam	RTMD	31
	Sabarmati	SBTD	22
West Central Railway	New Katni Jn.	NKJD	8
Total Locomotives Active as of May 2026			375

Technical specifications

Technical details are as follows:

Manufacturers	DLW
Engine	Alco 251-C, 16 cylinder, 3,100 hp (2,300 kW), (3,007 hp or 2,242 kW site rating, earlier 2,900 hp (2,200 kW)) with Napier NA2951R/ ABB VTC-304-VG15/ GE 7s 1716 turbo supercharged engine. 1,050 rpm max, 400 rpm idle; 228.6 mm × 266.7 mm (9.00 in × 10.50 in) bore x stroke; compression ratio 12.5:1. Direct fuel injection, centrifugal pump cooling system (2,457 L/min (540 imp gal/min; 649 US gal/min) at 1,050 rpm), fan driven by eddy current clutch (90 hp or 67 kW at 1,050 rpm)
Governor	EDC / Woodward 8574-650
Transmission	Electric, with BHEL TA 10102 CW alternator (1,050 rpm, 1,100 V, 4,400 amperes) (Earlier used BHEL TG 10931 AZ alternator)
Traction motors	BHEL TM 4906 AZ/ 4907 BZ (435 hp or 324 kW) (with roller bearings)
Axle load	18.8 tonnes (18.5 long tons; 20.7 short tons), total weight 112.8 t (111.0 long tons; 124.3 short tons)
Bogies	Alco High Adhesion Fabricated Bogies
Starting TE	40 t (39 long tons; 44 short tons) at adhesion 30.8%, continuous 37.05 t (36.46 long tons; 40.84 short tons)
Length over buffer beams	17,850 mm (58 ft 6+3⁄4 in)
Distance between bogies	11,500 mm (37 ft 8+3⁄4 in)

See also

• Indian locomotive class WDM-3A
• Indian locomotive class WDM-2
• List of diesel locomotives of India
• Indian Railways
• Rail transport in India