Apparatus for detecting ruptures in drill pipe above and below the drill collar
An apparatus for detecting ruptures in a drill pipe above and below the drill collar comprising a nose cone, a lower body threadably engaged to the nose cone. The lower body has a structure defined by a plurality of circulation by-pass apertures and shear pin apertures. A cylinder actuator having actuator apertures is installed within the lower body juxtaposed to the shear pin apertures. Shear pins slideably lodge through the shear pin apertures of the lower body into the actuator apertures of the cylinder actuator. A steel ball seats on top of the cylinder actuator. An upper body threadably engages the lower body and a retrieval cap threadably engages the upper body. The apparatus seats into a seating sub in operation of the invention. The method of detecting and correcting ruptures in a drill pipe above and below the drill collar to prevent loss of drill mud comprises running a seating sub in the drill string at the top of the drill collar and subsequently dropping a washout locator tool into the drill pipe until the tool seats in the seating sub. The drill string is pressurized above the seated tool to a predetermined pressure. The predetermined pressure is monitored to ascertain whether or not the predetermined pressure holds without bleeding off, indicating that there is no noticeable leak in the drill string between the tool and the surface, or doesn't hold and bleeds off indicating that there is a leak. If the pressure holds without bleeding off, shearing pins are sheared in the tool to establish circulation and the drill stern is pulled dry and the bottom hole assembly below the drill collar is checked. When the pressure does not hold, the drill string is pulled in order to detect and correct any ruptures which cause the decrease in the predetermined pressure.
- Assignee:
- EDB-84-177575
- Patent Number(s):
- US 4452306
- OSTI ID:
- 6361344
- Resource Relation:
- Patent File Date: Filed date 27 Sep 1982; Other Information: PAT-APPL-423863
- Country of Publication:
- United States
- Language:
- English
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