Full-bore drill stem testing apparatus with surface pressure readout

Abstract

In accordance with an illustrative embodiment of the present invention, a full-bore drill stem testing system includes a lower housing member having a ball valve for opening and closing a flow passage extending axially therethrough and an upper housing member having an open axial bore in communication with said flow passage. Downwardly facing recesses are formed in the wall of the upper housing member laterally offset from the open bore, and each recess receives an electrical contact that is connected with transducer means for sensing variables such as pressure and temperature of well fluids below the ball valve. Guide slots having orienting surfaces at their lower ends lead upwardly to each recess. A running tool that is lowered into the upper housing member on electrical wireline has normally retracted arms which carry electrical contacts on their upper ends. The running tool is actuated upon engagement with a stop shoulder in the upper housing member to cause extension of the arms, whereupon the running tool is shifted upwardly to cause the upper ends of the arms and the contacts thereon to be oriented and guided by the slots into engagement with the contacts in the recesses. The electrical connections thus made enable surface readout of the downhole measurements as the drill stem test proceeds.