| Class DD15 | |
| Powertype: | Diesel-hydraulic |
| Builder: | Nippon Sharyo |
| Builddate: | 1961–1966 |
| Totalproduction: | 50 |
| Britishclass: | Bo-Bo |
| Width: | 2926mm |
| Height: | 3880mm |
| Axleload: | 15.5 t |
| Locoweight: | 62.0 t |
| Fueltype: | Diesel |
| Fuelcap: | 1,500 l |
| Rpmrange: | 1,500 |
| Enginetype: | DMF31SB x 2 |
| Transmission: | Hydraulic |
| Maxspeed: | 70abbr=onNaNabbr=on |
| Poweroutput: | 1000hp |
| Tractiveeffort: | 16500kgf |
| Numinclass: | 6 |
| Deliverydate: | November 1961 |
| Preservedunits: | 3 |
| Disposition: | In service |
The is a four-axle Bo-Bo wheel arrangement diesel-hydraulic locomotive type operated in Japan as a self-propelled snowplough unit since 1961 by the national railway company Japanese National Railways (JNR), and later by East Japan Railway Company (JR East) and West Japan Railway Company (JR West). A total of 50 locomotives were built between 1961 and 1966, and, 6 locomotives remain in service.
A total of 50 locomotives were built between 1961 and 1966, divided into the following sub-classes.[1]
The Class DD15 was developed from the Class DD13 locomotive design, with the addition of snowplough units at either end.[1] The snowplough units could be detached, allowing the locomotives to be used for shunting and other duties outside the winter periods.[1] However, with the snowplough units mounted, the locomotive axle load was nearly 16 t, restricting use on rural lines, and so the class was superseded by the later Class DE15 locomotives, which had separate snowplough units.[2] As with the Class DD13 locomotives, the Class DD15 had two 500hp DMF31SB diesel engines.
46 Class DD15-0 locomotives were built between 1961 and 1965 by Nippon Sharyo,[1] with the first locomotive delivered in November 1961.[3]
, six Class DD15-0 locomotives remain in service.[2]
Four Class DD15-300 locomotives were built in 1966 by Nippon Sharyo.[1] These locomotives had a modified gear ratio, changed from 1:3.143 to 1:3.196.[1]
, no Class DD15-300 locomotives remain in service.[2]
At the time of privatization of Japanese National Railways (JNR) on 1 April 1987, 32 Class DD15 locomotives remained in service, with JR East receiving 19 and JR West receiving 13.[4] By 1 April 1995, 25 locomotives were still in service, operated by JR East and JR West, including two DD15-300 locomotives.[1]
, six locomotives remain in service, all operated by JR West.[2]
, three Class DD15 locomotives are preserved.[5]
See main article: Japan Railways locomotive numbering and classification. The DD15 classification for this locomotive type is explained below.