Answering a question by member upwpfan in the HO scale section.
First of all, D52 heavy mikado type.
Most famous use was on the Gotemba Line, hauling local passenger trains between Kozu and Numazu. Typically a 5 car consist, with a coach/baggage at the front end for down trains (suhani type):
http://home.a00.itscom.net/yosan/jyoki/gotenba/gotenba.html (first section)
D52 types were also used on passenger/parcels trains on the Hakodate Main Line between Oshamambe and Hakodate. Most notably, trains 41/42, a passenger and parcels train between Sapporo/Otaru and Hakodate via the Hakodate Main Line "mountain route". D51 haulage between Otaru and Oshamambe, then D52 to Hakodate.
This is a sequence of train 41 arriving at Mori Station and taking on water (1972):
http://blogs.yahoo.co.jp/br1020er/25809575.html