Wedge Gate Valves Prevent Leaks in Emergency Shutdown Systems

In the Middle East and North Africa (MENA), the oil and gas market is highly competitive. Petrochemical plants must provide services with as little disruption as possible to maintain production and meet market demands. These facilities handle hazardous materials that require constant monitoring, and the equipment in these challenging environments is typically difficult to access and maintain. Unplanned plant shutdowns delay and disrupt production, resulting in substantial financial losses. Shutdowns often result from failures in system components, such as valves. As plant infrastructure evolves, specialized valve engineering promises reliable performance in challenging applications, such as chemical and petrochemical handling.

Design Specifications

An integrated petrochemical facility in the Middle East needed to install large valves for wet flare applications. The installation had to occur by a strict deadline without disrupting plant operations. The plant operator required a complete valve solution that included design and engineering support, valve casting and testing to stringent standards, and delivery and installation at the facility. The valves measured 78 and 84 inches (1.9 and 2.1 meters) in diameter—the largest wedge gate valves the manufacturer had ever produced. The manufacturer had to develop a complete valve design, including all components, in accordance to its internal finite element analysis (FEA). The design needed to contain the valve as a whole as well as every component to make sure each detail was considered during the process. The components were machined separately during production according to this extensive data and as part of the entire valve construction. The project took about 11 months to complete, from receiving the approval from the plant operator to manufacturing, benchmarking and delivering the valves to the Middle Eastern plant. The large-diameter valves were delivered on schedule without any delays. Bolted bonnet-flanged wedge gate valves are the preferred valve design for petrochemical plants. Wet flare applications require high performance and tight shutoff. Wedge gate valves drain excess gases and operate in critical safety systems to provide emergency shutdown and prevent leaks.

Testing & Installation

The team of engineers first accumulated performance data about the required wedge gate valves and studied the challenges in manufacturing valves of this size. Because 78- and 84-inch valves are not covered by international design standards, the manufacturer analyzed the information about pressure and temperature performance requirements. Based on the results, the engineering department carried out the necessary calculations for manufacturing the valves. Team members considered the weight of the valves, their thickness, size, material, pipe connection and pressure. The specialized carbon-steel body and ANSI Class 150 pressure rating offered improved fluid passage and optimized flow compared with other valves. The bolted bonnets allowed the valves to be sealed tight to prevent leaks and work effectively in emergency situations. The manufacturer tested the wedge gate valves at a production facility in Rescaldina, Italy, which features one of the largest test benches in Europe. The team performed extensive testing in accordance to API 598 valve standards. Raw castings were tested, and magnetoscopic dye penetration was carried out on all components before and after the machining. This was all done before delivering the complete valves, each weighing 15 tons, to the plant for installation. During the last phase of the project, experts provided comprehensive on-site technical support, ensuring all procedures complied with the plant operator's standards.