Launch system for a pressurized pipeline

A launch system for a pressurized pipeline, the launch system including a seal arrangement, comprising:

• a chamber attachable to the pipeline such that an open end of the chamber is in fluid communication with an interior of the pipeline;
• a seal disposed in the chamber such that at least a portion of a first side of the seal is exposed to pressurized gas inside the pipeline when the chamber is attached to the pipeline, the seal having a second side disposed opposite the first side and a generally cylindrical inside surface sized to contact an outside surface of a cable extending from outside the pipeline to inside the pipeline such that release of the pressurized gas between the inside surface of the seal and the outside surface of the cable is inhibited;
• and
• a vent disposed within the chamber adjacent to and contacting the second side of the seal, the vent having a generally cylindrical inside surface sized larger than the inside surface of the seal.

A launch system for a pressurized pipeline, the launch system including a seal arrangement, comprising:

• a seal configured to engage a cable extending from outside the pipeline to inside the pipeline such that release of pressurized gas from inside the pipeline to an ambient environment outside the pipeline through the seal arrangement is inhibited;
• a vent disposed axially adjacent to the seal such that it receives gas passing between the seal and the cable, the vent being configured to direct the received gas to a predetermined location, the vent including a channel disposed in an outside surface thereof and at least one aperture disposed in the channel and through an inside surface of the vent such that gas received on an inside of the vent can pass through the at least one aperture and into the channel;
• a chamber attachable to the pipeline such that an open end of the chamber is in fluid communication with an interior of the pipeline, the outside surface of the vent being in sealing contact with a wall of the chamber, the wall of the chamber having an aperture disposed therethrough in fluid communication with the channel of the vent for providing egress for the gas to an environment outside of the chamber;
• and
• a compression ring contacting a side of the seal and configured to impart an axial force and a radial force to the seal when the seal is axially compressed.