ECR has a long list of trains in this category of average speeds of 30-40 kmph.
CPU- GMO Exp
CPU-PRYJ Exp
RGD-DNR...
more... Exp
Sgrl Pnbe Exp
SGRL- BSB Exp
DNR SBG Exp
Pnbe SSM SPL
SKTN-BSB Exp
Pnbe JYG Exp
PNBE- BBU Exp VIA Gaya
Just above 40 kmph
PNBE- BBU Exp VIA ARA
Kosi Exp
Palamu Exp
Train of other zone in bihar with less avg speeds
Pnbe MLDT EXP ( ER)
Katihar pnbe Intercity ( NFR)
BGP- Pnbe inrercity ( ER)