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Port Said East Power Plant
Port Said East Power Plant
Port Said East Power Plant
Port Said East Power Plant
Port Said East Power Plant
08-09-2014

Egypt, 2010

In 2004, Port Said East Power Plant Station found ex-filtrating joints in three 2300 mm Glass Reinforced Pipes (GRPs). These pipes were used as cooling water recirculation lines operating under pumping pressure.

Cemtex-Link-Pipe in Cairo was contacted for pricing, but at that time, a lower priced product was selected.

Two years later in 2006, the pipes were found again to be in need of repair. The lower priced product was reinstalled again in 2008. At that time 17 of the repaired joints were again found to be leaking. This number had increased to 23 leaky joints by January 2010.

Cemtex-Link-Pipe was contacted again and five most critical joints were selected to be repaired with Link-Pipe sleeves. The project started on March 16th, 2010 and was completed by March 23rd.

PROBLEM DESCRIPTIONS:

It was found that all of the problems were due to offset joints in the host pipes. The previous repair method had not stabilized the joints due to their flexibility, and had allowed joint movement to continue without restraint. Link-Pipe at that point had accumulated 24-years of experience in developing technology. In discussion with the owners, it was revealed that the conduit was embedded in sandy water-bearing soil. It became obvious that these pipes lacked the needed rigid support for joints. A flexible coupling could not provide the required rigidity. Link-Pipe is designed realizing that rigidity of its structure is important.

LINK-PIPE SOLUTIONS:

Link-Pipe PVC sleeves were specified. Two successful above-ground dry runs and five successful repairs were conducted by divers from HMS Company. During the above-ground testing the installation crew was trained. THis experience permitted the divers to gain familiarity with the process that helped them to install the slee

Direct on-line communication between divers in the pipe and engineers on the surface enabled to overcome visually deteceted problems after failed repair materials were removed.

Standard man-holes were used for personnel access. It helped that Link-Pipe sleeves could be inserted separately through much larger surge tank. This avoided the need to insert the sleeve parts which would have required them to be assembled inside the inundated pipe before installation.

LESSONS LEARNED:

IMPORTANT EARLY INSPECTION

Prior to the start of the project, Cemtex Link-Pipe faced the problem of not having been able to conduct a prior inspection behind the old repairs. Instead, they had to rely on an inspection report compiled by a third party who had neither experience of Link-Pipe technology nor an understanding of what the requirements are for comprehensive inspections associated with Link-Pipe technology. This third party inspection report was the only available record on the condition of the leaking conduit. Furthermore, no opportunity was available to assist the selected inspectors to become familiar with Link-Pipe technology needs. Thus only partial information was available on the internal conditions of the pipes.

To prepare the leaking joints for Link-Pipe installation, the remnants of previous repairs had to be removed. This revealed joint offsets of which some exceeded the normal design allowances built into the standards for the repair sleeves.

In one case, an unanticipated corrective technique was devised on the spot for a sever misalignment. It necessitated acquiring special sealant that had to be brought in from Cairo.

When another failed flexible rubber repair sleeve was removed, a joint offset exceeding 35 millimeters was exposed. It was felt that it would be too risky to use hydraulic force to push the pipe back into alignment as such force would break the fragile host pipe. Instead a solution by creating quicksand conditions in the surrounding sandy backfill using water pressure from a local fire hydrant presented as a suitable option. During this process, counter-pressure was applied by the Link-Pipe PVC sleeve, which facilitated the pipe realignment and repair.

This solution corrected the offset with no damage to the host pipe, and stabilized the joint.

CONCLUSIONS:

  1. It is highly beneficial to have good prior information in order to avoid surprises and resulting delays.
  2. Prior above-ground training was found to be critical in facing the unanticipated conditions found in the pipe.
  3. The removal of previously installed and failed rubber repair sleeves revealed hidden joint-offsets that exceeded anticipated design parameters. These could be overcome by utilizing locally available high-pressure water supply.
  4. All five authorized joints were successfully sealed.