部面 is read as ぶめん (bumen) and means phase.
ぶめん
bumen
めんぶ
face
ひょうめんじっそうぶひん
surface-mount device
ぶちょう
head (chief, director) of a section or department
ぶぶん
portion
ぶひん
parts
ぶか
subordinate person
へや
stable
ぶしゅ
radical (of a kanji character)
ぶかい
section meeting
ぶいん
staff
ぶない
the staff
ぶすう
number of copies