Positive circulating valve with retrievable standing valve

摘要

A positive circulating valve with a retrievable standing valve therein. The valve is used with a packer positioned therebelow. The circulating valve comprises a housing with a mandrel slidably disposed therebetween. A J-slot controls movement between open and closed positions. When in the open position, mandrel ports in the mandrel are aligned with body ports in the housing so that bypassing and circulating may be carried out. The standing valve prevents fluid flow downwardly through the tool string below the circulating valve when the circulating valve is in the open position. When the circulating valve is in a closed position, the mandrel ports are in communication with a central opening through the housing, allowing fluid to be pumped downwardly through the circulating valve. The standing valve may be removed so that the circulating valve has a substantially unrestricted flow path therethrough for high flow rate fracturing jobs and the like.