Life Extension of 30+-Year-Old Cables
Hess Corporation is a global integrated energy company headquartered in New York City engaged in the exploration and production of crude oil and gas. The Hess Port Reading refinery’s fluid catalytic cracking unit is capable of producing 70,000 barrels per day of some of the cleanest-burning gasoline available. Its tank field can store up to six million barrels, and its terminal can transport product by truck, ship, barge, rail and pipeline. The refinery was established in 1958 and many of the medium voltage cables are over 30 years old.
Prior to the Novinium injection project, Hess refinery had experienced two ground fault current trips. The trips caused the main feed to the refinery to trip. These outages, lasting up to 12 hours, cost the refinery millions of dollars in downtime.
Cable Injection Project:
A project kickoff meeting was held to walk the project and define each of the accessories required, so that they could be ordered in advance. After an initial one day delay waiting for circuit availability, the project started. One 350 MCM EPR and four 500 MCM XLPE 3-phase 5 kV cable circuits, which were direct buried and encased in concrete, were injected in a period of four days. The project was completed ahead of the scheduled startup. There were challenges removing the old heat shrink termination kits that had been in place for a very long time.
The Cable Injection Process:
After cables are de-energized and grounded, the old terminations are removed. If there is no slack, a lug splitter is used to remove the old lugs. A template is use to determine the proper cutback, and each cable end is prepared as shown in the picture above. Then an injection adaptor (IA) is installed on the cable. The IA seals the end of the cable, keeps the fluid from touching the terminations or splices, and prevents any future moisture from getting into the cables, even if there is a flood. Once the IAs are installed on each cable end, an injection valve is mounted on the IA (above picture) and is connected to the pressurized tank. The fluid flows from one end of the cable to the other in just a couple of hours. Both IAs are then sealed, and new termination kits are installed. The cable is reconnected and re-energized. Within 7 days the dielectric strength of the cable has improved to the point where it is unlikely to fail. After injection, these cables will last another 40 years.