Highest level of automation for offshore unloading and loading buoys

Around the world, Bluewater Energy Services' offshore buoys are located where tankers can moor to load or unload liquid cargo. In cooperation with industrial automation company EKB, Bluewater has standardized the control of the buoys on Siemens technology. This represents a major efficiency improvement.

A refinery is under construction in Dos Bocas that will make Mexico self-sufficient in refined petroleum products. About ten kilometers off the coast, three loading and unloading buoys are anchored in the seabed. These so-called Turret Buoys will be connected to the refinery via a pipeline across the seabed. In the future, tankers will dock there. Through two of the three buoys, refined products can be pumped from shore to the tankers for shipping. The third buoy is for the supply of a raw material needed in the refining process.

Long lifespan

Bluewater Energy Services has been producing loading and unloading buoys for nearly 40 years. They are used in locations where there is no port infrastructure to allow tankers to moor. Unique to this type of buoys is the fact that they rotate in their entirety with the ship, allowing ships to stay longer in bad weather. Specific to the Bluewater turret buoy design is the use of a deckhouse, which allows the control electronics to be housed clean and dry on top of the buoy. This adds to the longevity of these systems so Bluewater's buoys can last up to 30 years without the need for a retrofit. Very efficient since removing, hauling over and putting back a buoy is very costly.

Standardization

Until a few years ago, the buoys built by Bluewater were customized. The automation was a combination of different technologies and therefore different interfaces. Standardization in cooperation with EKB has made a major efficiency improvement. "Our projects now have shorter lead times and are more manageable," says Bart van den Ban, project manager at Bluewater. "EKB has built the control system in a modular way. This still allows us to meet specific client needs. Customers who want additional functionality can add separate modules. Because maintenance has been simplified, we can provide a better after-sales service."

Choice of Siemens

EKB has already helped many large companies with standardization projects, which account manager Ronald Molenbroek says lays the foundation for a long-term cooperation. "In consultation with Bluewater, we chose Siemens' Simatic S7-1500 PLCs as the control system. Siemens' technology is familiar in the offshore and a big advantage is that service is well arranged all over the world. Because of the often harsh conditions at sea, we use a robust SIPLUS controller. This line was developed by Siemens for extreme conditions and includes a wider temperature range and special coatings that protect against aggressive gases. Engineering the control components we do in the TIA Portal."

Continuous improvement

The standardization process is a continuous process. With each new project, EKB makes further optimizations. "We are working toward a plug-and-play solution that you cannot connect wrongly, that works immediately and that can be accessed remotely," says Erik Schoonbergen, manager of EKB's Beverwijk office. "With the first buoys, you needed separate cables for each instrument, but we have now switched to a redundant Profibus connection for all instrumentation. The cables have been tested beforehand and are also suitable for an ATEX environment." Florentina Golea, project engineer at Bluewater, responds, "This has allowed us to reduce the commissioning time and we need less space for the cabling."

High safety level

The buoys for the Dos Bocas project are 10 meters in diameter and are powered by solar panels. The pressure and temperature of the oil is measured in the buoy and automatically transmitted to the control room in the refinery. From the control room, the load on the mooring cable can also be continuously monitored. When conditions become too extreme, the safety system can automatically disconnect the vessel to prevent damage. Considerable bandwidth is required to send all data to shore, but the client wants nothing left to chance and to be able to intervene quickly in case of problems or calamities. Golea: "For safety reasons, the tanker's crew can use an industrial tablet (Simatic Mobile Panel) to see how far away they are from the buoy and what the ship's direction is in relation to the buoy. The tablet is also equipped with an emergency button."

Remotely accessible

All buoys come standard with a remote unit so they can be accessed remotely. "We started doing that during the corona period," Golea explains. "At that time it was not possible to start testing at the yard where the buoys are built." Molenbroek recalls that at one point three engineers from different countries were commissioning together. "With Siemens' technology, that's very doable and it saved us a lot of travel time." Bluewater can improve after-sales support thanks to the remote unit in the buoys. For example, if customers want to get more data out of a buoy, additional functionality can be added to the software remotely.

Technology partnership

EKB considers itself a technical partner of Bluewater. Bluewater also sees it that way. "They take a lot of work off our hands, allowing us to respond better to our clients' increasingly high expectations," Van den Ban said. Underlying this partnership is the strong relationship between EKB and Siemens. EKB has been a Siemens Solution Partner for many years. "We invest a lot in our partners," says Huibert Winckers, product marketing manager Drives & Motors at Siemens. "As a technology company, we need integrators to solve complex issues of end customers to deliver added value with our products. EKB is strong at that. They also have knowledge of specific markets that we don't have ourselves."

Highest commitment

Bart van den Ban explains how Bluewater benefited from the strong relationship between EKB and Siemens during the Dos Bocas project. "This project had been offered to the client for a long time, but when implementation started there were delivery problems worldwide. Siemens, as a result of Covid, made it possible for us to test with a regular PLC during the FAT while we were still waiting for the SIPLUS." Molenbroek: "This is how Siemens helps us as a partner to fulfill our agreements with customers even under difficult circumstances. In the end, the commissioning of the 3 buoys in the yard took only a week and a half!"