Improved Unsustained Pressure Rejuvenation (iUPR)
Our iUPR process is a good choice for segments in outage-adverse areas where splices are flowable, difficult to access, or cost prohibitive to replace. The process requires only one switching event and is backed by up to a 25-year warranty.
Improved Unsustained Pressure Rejuvenation uses low pressure (15–30 psi) to flow fluid through splices while the circuit is energized, making it the choice for injecting hard-to-reach splices or radial segments.
- Saves time because it doesn’t require two switching events.
- Allows for complete injection in a single day.
- Extends cable life up to 25 years.
- Is value conscious—the choice when it’s not economical to replace a cable splice.
- Eliminate the risk of injection port flashover, with our reticular flash-prevention (RFP) technology.
- Employ more robust and redundant seal designs that reduce fluid leaks and the probability of transformer fires.
- Eliminate the need for postmanufacture air-pressure testing to identify flashing from molding defects.
- Reduce the oozing of treatment fluid from the elbow by 30 percent during and after injection. Fluid secretion can compromise elbow reliability under hot conditions and lowers the post-injection reliability of the cable in all cases.
- Isolate, test, and ground the cable.
- Use a TDR device to check every segment for splices, neutral corrosion, and length.
- Perform an airflow test and, if a splice is present, a pressure test. Confirm the fluid will flow and the splice is suitable for injection.
- Install new connectors and injection elbows.
- Connect the feed tank to the injection elbow at one end of the cable.
- An injection technician installs a receiver tank at the other end of the cable.
- Re-energize the segment with the injection equipment attached, start the injection process, and close the transformer. The segment is typically de-energized for 30 minutes or less.
- We inject the cable at 25 psi or less. The injection process typically takes 24 hours or less to complete.
- Our technician returns after the injection is complete to collect the equipment, which is designed to allow safe removal while the cable is energized.