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bottomhole gas separator

1. n. [Production Testing]
 A perforated tubular attached to the subsurface sucker-rod pump that controls the entrance of gas. Since it is the only way for formation fluid to enter the pump, its use increases the efficiency of the subsurface sucker-rod pump. It also helps to prevent the phenomenon called gas lock. A gas anchor is similar to a bottomhole gas separator.
Synonyms: gas anchor