# Indian locomotive class WAP-6

The Indian locomotive class WAP-6 was a class of 25 kV AC electric locomotives that was developed in the mid-1990s by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), AC Current (A), Passenger traffic (P) locomotive, 6th generation (6). They entered service in April 1996. A total of 17 WAP-6 units were built at CLW between 1995 and 1998.
The WAP-6 were intended to be a higher-speed variant of the WAP-4, but were restricted to a top speed of 105 km/h after failing trials. All were based at Asansol (ASN) shed, but after conversion to WAP-4 specifications, they were reallocated to Howrah (HWH) shed.

## History

This class was a regeared variant of the WAP-4 mounted on Fabricated Flexicoil Mark IV bogies, instead of the standard Co-Co Flexicoil Mark 1 cast bogies seen on other WAP-4 locomotives. All other specifications were same as WAP-4. WAP-1 no.22212 was the first to be rebuilt into a WAP-6, being fitted with Flexicoil bogies and other upgrades; it was later rebuilt into a WAP-4. Subsequently, 16 more WAP-1 units were re-geared and mounted on Flexicoil Mark IV high-adhesion bogies, which are similar to high-adhesion bogies made by ALCO. Renumbered to 22400–22416, they were intended for 160 km/h (99 mph) operations, but in trials, they were unable to reach that speed and were therefore restricted to 105 km/h (65 mph). Two units, 22406 and 22408, were upgraded with better wheel-sets. This class was unsuccessful, with most locomotives of this series being converted back as WAP-4.

## Technical specifications

Technical specification :
| Traction motors | Axle-hung, nose-suspended, force-ventilated, 3,485 kg (7,683 lb), 630 kW (840 hp), 750 V, 900 A, 895 RPM, parallel grouping, C class armature and field, temperature rise (Armature 60, filed 70 and commutator 85) in °C, coil resistance (armature 0.01284 ohms+10%, field 0.01184 ohms+10% and commutator 0.00907 ohms+10%, air gap main pole 6.35 kVA, air gap inter-pole 10 mm (0.3937 in) |
| Gear ratio | 58:23 |
| Transformer | CCL make, aluminium coil, 3400 kVA, 32 taps |
| Rectifier | 2 silicon rectifier cubicle 2700 A, 1050 V |
| Number of sandboxes | 4 |
| 2 Headlights | 250 W, 32 V |
| Lead acid Battery | 50 cells, 110 V (rated 5 hr) |
| Arno Converter | 216 kVA |
| 2 FLAKT smoothing reactor blower | PHMX-40 |
| 2 Silicon Rectifier Blower | 60 kg (132 lb) |
| Oil cooler blower | S.F. India Ltd. |
| Smoothing reactor for traction motor | SL-30 type, 1350 A, 1270 V, 2 Coils, 0.00535 ohms resistance at 110 °C (230 °F) |

## Hauling capacity

If the average weight of ICF coaches is 55 tonnes then:
| Grades/km/h | Start | 20 | 40 | 60 | 70 | 80 | 90 | 100 | 110 | 120 | 130 | 140 | 150 | 160 |
| Level | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1155 | 805 | 570 |
| 1 in 500 | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1105 | 805 | 565 | 400 |
| 1 in 200 | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1320 | 1230 | 1035 | 730 | 535 | 375 | 260 |
| 1 in 150 | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1500+ | 1405 | 1090 | 1020 | 860 | 610 | 445 | 310 | 215 |
| 1 in 100 | 1500+ | 1570 | 1490 | 1405 | 1365 | 1195 | 1020 | 795 | 750 | 635 | 445 | 320 | 220 | 145 |
| 1 in 50 | 1160 | 770 | 750 | 720 | 710 | 625 | 530 | 410 | 390 | 325 | 220 | 150 | 90 | 45 |