Abstract: A subsea drill-thru manifold center for petroleum well completion and production is disclosed. The manifold center is compartmented so each well is within its own gas tight compartment. A removable sleeve through which the well is completed is mounted in each compartment. After each well is completed its sleeve is removable so it can be put in production in the conventional manner.

Abstract: A gauge for measuring the distance and angle between two pipes is disclosed. The gauge consists of an elongated tubular body section adapted to be rigidly affixed to one of the pipes and including an extendable probe. A target plate is fitted over the other pipe and the extendable probe is brought into contact with the target plate. The angle between the target and the extendable probe, the eccentricity of the extendable probe and the target plate and the length of the combination of the tubular body and the extendable probe gives sufficient dimensions for cutting a curved section of pipe or pup.

Abstract: Apparatus includes an offshore platform riser subtended by a joint chamber having port means for receiving a subsea pipeline and access means for a submersible capsule. The riser and chamber are attached to the platform in such manner as to provide for thermal expansion and to permit detachment when an abnormal loading is encountered. Platform winch means attached to cable means passing through the riser and chamber are used to pull an end of the pipeline into the chamber. Personnel utilizing the capsule then enter the chamber for completing the joining of the pipeline and riser. The joining and subsequent inspection operations are conducted at substantially atmospheric conditions in the chamber.