Touchpoint Inspection, Composite & Mechanical Repairs
Overview
To ensure the ongoing reliability of a strategically vital refinery, Ovolifts engineered the lifting, inspection, and repair of 405 pipe touchpoints across three levels of a crude unit’s pipe rack over a five-week period.
The objective was to facilitate the remediation of severe touchpoint corrosion, thereby eliminating the risk of unplanned shutdowns that could result in daily losses of $5MM.
Ovolifts’ unique ability to lift multiple lines simultaneously allowed the project scope to be completed two weeks ahead of schedule. Ovolifts’ responsibilities included pipe stress analysis, design and supply of specialized lifting equipment, emergency response planning, and on-site supervision to guarantee safety and efficiency throughout the project.
The Need and Challenge
The refinery, with a production capacity of 100,000 barrels per day, was three years away from its next planned turnaround. However, it faced immediate threats from touchpoint corrosion in its piping systems. Previous incidents of loss-of-containment had resulted in costly shutdowns lasting multiple days, prompting the facility to take proactive measures.
The project scope targeted 45 pipe supports on three levels of a rack within the crude unit. It focused on touchpoints where lines rested directly on bare I-beams or I-beams coated with sprayed cementitious fireproofing. These touchpoints posed significant challenges: the bare supports facilitated corrosion through metal-to-metal contact and water pooling at the pipe touchpoints, while the fireproofing retained moisture, exacerbating corrosion and embedding the lines into the material over time.
Access within the multi-level pipe rack was also congested with many obstructions, preventing the use of traditional lifting methods such as cranes. Additionally, the high volume of lifts required made single lifts at a time unproductive.
Solution and Outcome
Ovolifts deployed a tailored approach to lift and access the identified touchpoints, utilizing a combination of advanced lifting techniques, industry best practices, and comprehensive engineering analysis, including pipe stress analysis and detailed lift planning.
Before lifting each pipe, wall thickness readings were taken at multiple locations around the touchpoints to thoroughly assess the pipe’s condition. This data was crucial for evaluating the integrity of each line prior to lifting. Each lift began with a small "breakaway" separation, raising the pipe just 1/8th of an inch from its support. This initial movement was enough to determine if there were any signs of leakage.
At this point, an inspector entered the area to verify the pipe’s integrity before proceeding to the final lift height of 2 to 3 inches.
Lines with severe wall loss were mechanically enclosed using pre-fabricated clamps to ensure their integrity until the scheduled turnaround. For areas exhibiting moderate corrosion or pitting, composite wraps were applied to restore the pipe’s wall thickness.
In less critical cases, epoxy coatings were used to arrest further corrosion, and corrosion mitigation pads were installed to eliminate metal-to-metal contact and prevent water accumulation. This meticulous approach not only addressed the immediate risks but also implemented preventive measures to safeguard against future issues.
The project was executed with exceptional efficiency, leveraging Ovolifts’ purpose-designed tools and refined procedures to complete the scope of work two weeks ahead of schedule. The refinery benefited not only from the immediate remediation but also from the detailed data collected for 405 touchpoints, providing valuable insights for ongoing maintenance and corrosion rate tracking.
The overall project cost—including scaffolding, repair clamps, engineering services, specialized equipment, and personnel—was significantly less than the potential $5MM daily loss the plant could incur during an unplanned shutdown.
Emergency Response Planning
A critical aspect of the project was the implementation of comprehensive emergency response measures to ensure the safety of personnel and the facility during lifting operations.
Portable water cannons were strategically positioned on the pipe rack, aimed at the areas where touchpoints were being lifted. These cannons were connected to nearby fire hydrants via fire hoses, providing a rapid and targeted response in the event of a leak or fire. Each lift was closely monitored by a representative from the plant’s operations team, who had detailed knowledge of the products in each line being lifted.
The on-site operator maintained constant communication with their team in the operations building via radio and was in charge of the lifting operation. In the event of a leak, for example, the operator was responsible for activating the water cannons or directing the team to perform an emergency shutdown.
This expertise allowed for an immediate assessment of any potential leaks, identifying the associated risks and determining the appropriate response. For instance, a minor leak in a cooling water line presented negligible risk, while a leak in a hydrocarbon line could pose significant hazards.
All personnel involved in the lifting operations were equipped with 5-minute escape packs, which included full-face respirators providing a fresh air supply. These packs allowed workers to evacuate the area safely in case of a hazardous leak. Leak sealing teams, staged nearby, were outfitted with similar respirators connected to larger air supplies, enabling them to re-enter the area and address leaks using pre-fabricated mechanical enclosures.
These clamps, designed to fit the exact dimensions of the piping, were bolted into place and injected with a sealant to close any gaps between the pipe surface and the enclosure. This method ensured that leaks could be sealed without requiring a shutdown, preserving the plant’s operational continuity.
To further mitigate risks, the operations team ensured the locations of all isolation valves were identified and accessible, enabling a quick shutdown of affected lines if necessary. In cases where isolation was not possible, the plant was prepared for a controlled shutdown.
While the possibility of a loss-of-containment, however small, could be used as a reason to avoid live line-lifting programs altogether, it is far preferable to address a leak under controlled circumstances with a response plan, personnel, and resources on-site. Any touchpoint that could potentially leak during a lift is already severely compromised, making it likely to fail during normal operations in the near future.
Additionally, due to the production losses associated with a turnaround, most aging plants only schedule them every two to four years. Therefore, restricting this work to a turnaround is inherently risky and increasingly insufficient to address all the touchpoint corrosion these plants experience.
Another option is to extend a turnaround to accommodate these repairs or even replace the pipe entirely. However, these options add significant pressure to the plant's economic operation. In such cases, difficult decisions must be made to accept the inherent risks of lifting live lines, even with a small chance of compromise. However, by employing the safest possible lifting and remediation practices, these risks can be effectively mitigated, ensuring the integrity of the plant's operations while addressing critical maintenance needs in a cost-effective manner.
Conclusion
The success of this project demonstrated Ovolifts’ unparalleled expertise in engineering safe and effective solutions for complex pipeline maintenance challenges. By safely engineering the lifting of 405 critical touchpoints with stringent safety protocols, the project not only mitigated immediate risks but also established a foundation for long-term reliability. The client’s confidence in Ovolifts’ capabilities has led to the initiation of similar projects across other facilities within their organization, further cementing Ovolifts’ reputation as a leader in pipeline lifting solutions enabling critical maintenance.
Comentários