Slow Circulation Rate Definition & Application
Well control operations are performed at reduced pump speeds or slow circulation rate in order to:

- Allow weighting up and degassing of the drilling fluid
- Reduce loads on surface equipment
- Increase reaction time for correct choke adjustments.

Operation of the pump at a pressure too close to the setting of its relief valve is dangerous. If the relief valve opens, drilling fluid will flow back through the drill pipe and standpipe manifold.
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