chemical plugging and channelling plugging

allowable shut-off time of fast shut-off valve

fall off [= bear off]

hang off [= stop off]

Off beat takes off

Off-Line Handwritten Chinese Character Recognition (off-line HCCR)

off-line trusted third party (off-STTP)

Off-on-off

one-off write-off

voltage cut off or current cut off

acid resisting plugging agent

acidization with temporary plugging

Acidizing Plugging Removal

adiabatic shear plugging

aggregate of plugging material

anti-plugging

Ash Plugging

auto plugging point tester

automatic plugging meter