Background and overview
Class DD13 B-B wheel arrangement diesel-hydraulic locomotive developed by Japanese National Railways (JNR) in 1957 had been operated for shunting and hauling branch line passenger and freight trains. Their higher axle load at 14 tons created a problem not to use on lower-grade tracks. They also created a problem having limitation for passenger trains caused by not having a steam heating boiler. These problems resulted in that they could not replace C58 and 9600 steam locomotive classes. For this reason, JNR needed rapid development of a new diesel-hydraulic locomotive to rationalize shunting duty and hauling branch line trains by replacing steam locomotives used on. JNR built four pre-production type of class DE10 diesel-hydraulic locomotives realizing low axle load at 13tons and having a steam boiler for passenger use in 1966.
Car body
The vehicle design fundamentally consists of low hood for good visibility
in both directions, a prime mover at the front, a steeple cab and a steam
boiler at the rear. The top of the hood can be opened to maintain cylinder
heads of a prime mover. Motorman's seats are fitted at the front and the
rear of the cab. A prime mover exhaust is fitted in the front centre of
the cab and a steam boiler exhaust is fitted in the rear centre of the
cab. Their livery is scarlet with grey upper surfaces separated by a white
stripe.
Bogies
Class DE10 adopts a 3-axle bogie, DT132, for the front and a 2-axle bogie,
DT131C, for the rear to realize that their axle load is within 13 tons
for use on lower class track and provide high braking performance. Since
3-axle bogie, DT132, normally raises lateral force against tracks, DT132
features the virtual center pivot to fit a propeller shaft throughout the
body and the construction that every linked driving axle freely moves.
Its bolster suspension is coil spring and gear boxes integrated with bearings
are connected with the truck frame by shock absorbing rubbers.
2-axle bogie, DT131C, also features the virtual center pivot keeping stability by bolster suspension's transverse stiffness to fit a propeller shaft. Its traction device is bolster-anchors. Their bogies employ double tread brake device not using pneumatic cylinders but rubber brake diaphragms.
Traction unit and auxiliary equipments
Class DE10 is powered by a DML61ZA diesel prime mover with a power output
of 1250PS developed based on DML61A adopted by class DD51 B-B wheel arrangement
diesel-hydraulic locomotive by featuring improved inlet air cooler circuit
to increase its power. Radiators and a cooling fan are fitted at the front
of the body. Sprinklers spraying water for a steam boiler onto radiators
are fitted to heighten cooling effect.
Their hydraulic transmission gear is DW6 based on DW2A employed by class
DD51, featuring the high/low speed switching clutch inside the reversing
gear and three types of hydraulic converters to optimize the hauling at
85km/h and shunting/piloting at 45km/h by choosing appropriate combination
of the clutch and the converter. Class DE10 also adopt multiple unit control.
They can also work with class DD51, DD53, and DD54 diesel locomotives.
The brake system features a self-lapping portion of the engineer's valve
and three-pressure type control valve to ease brakes operation.
A steam boiler, SG4B, is fitted behind the cab. Two fuel tanks are fitted under the floor and their total volume is 3050 liters. A water tank for a steam boiler is fitted at the end of the body and its volume is 2000 liters.
Variants
Standard variant locomotives delivered Kanto, Chubu, Kansai, and Kyushu regions are not equipped with snowplough.
Cold region A variant locomotives delivered to fierce cold regions, Hokkaido, Tohoku, and Hida to name a few employ the snow proof brake, snowplough, and rotary windows on the windscreens.
Cold region B variant delivered to San-in and Nagano regions are equipped with snowplough, and electric defroster devices on the windscreens.
Test running of pre-production locomotives
Two DE10 locomotives of standard variant were delivered to Matsuyama depot and two locomotives of cold region B variant to Ichinoski depot and underwent extensive test running. DE10 locomotives showed excellent performance for use on branch line passenger and freight trains. They also showed more excellent performance for use on shunting inside rail yards and piloting at stations than DD13.
Mass production type of -0 subclass
Mass production type of DE10 started to be delivered in 1967. They differ from pre-production type in having DT132A/DT131E featuring heat registed bogie frame. A water tank for a steam boiler is fitted under the floor and its volume is enlarged to 2500 liters. On the other hand, total volume of fuel tanks was made smaller to 2580 liters.
Improvement
DE10 locomotives built from 1969 differ from previous DE10 locomotives
in having more powerful prime mover, DML61ZB, with a power output of 1350PS
by getting improved fuel injection pumps and precombustion chambers, and
were classified into -1000 subclass.
DE10 1153 onward built from 1972 adopted new 3-axle bogie, DT141, simplifying link mechanism.
DE10 1188 onward built from 1973 are equipped with an electric fan under the ceiling of the cab and the cover for the electric fan is fitted on the roof of the cab.
Refurbishment
From 2001, a refurbishment programme was commenced on class DE10 for life extension and failure decreases. Their livery was changed into navy blue with grey upper surfaces separated by a white stripe. However, their livery was changed into grey with red upper body separated by a white stripe again.
Operations
Class DE10-0/-1000 locomotives had been used in shunting and piloting duties besides hauling branch line passenger and freight trains. Hauls duties had been decreased by replacement with electric/diesel multiple units, discontinuance of branch line freight trains, and discontinuance of branch lines. Shunting duties were also decreased by the change the rail freight transport system in 1984. Thus, DE10-0 locomotives had been withdrawn gradually.
At the splitting of JNR into the privatized JR companies, the six passenger railways and JR Freight of the JR Group received 4 DE10-0 locomotives and 173 DE10-1000 locomotives in 1987. DE10-0/-100000 locomotives have been withdrawn caused by decreasing train hauling duties by the progress of replacement with electric/diesel multiple units. Furthermore, they have also been withdrawn caused by decreasing duties of hauling work trains and deadheading vehicles
Class DE10-1000 locomotives operated by JR Freight have been used on shunting and hauling branch line passenger and freight trains. However, they began to be replaced with new hybrid diesel/battery Bo-Bo wheel arrangement shunting locomotives, HD300, and new Bo-Bo wheel arrangement diesel-electric locomotives, DD200, and are gradually being withdrawn. |
|
| Technical Data |
| Items |
Data |
| Traction transmission |
Hydraulic |
| Service speed |
85km/h |
| Max
power |
1,350PS |
| Length |
14,150mm |
| Width |
2,950mm |
| Total mass |
70.0t |
| Axle arrangements |
A0A0A0-B0 |
| 2 axle bogie |
DT131E |
| 3 axle
bogie |
DT132A (1001-1152), DT141 (1153-) |
| Prime mover |
DML61ZB (1,350PS/1550rpm) |
| Hydraulic transmission gear |
DW6 |
| Designed by |
Japanese National Railways |
|
|
