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stroke

1. n. [Production Testing]
In a sucker-rod pump, one complete round of the polished rod (surface stroke). On each stroke, a fixed volume of liquid is lifted. This volume is related to the cross-sectional area of the pump and the length of the stroke. The stroke length at the subsurface sucker-rod pump usually differs from the surface stroke because of the stretching in the upstroke and the rebounding in the downstroke.
See: rod pump