SPX Heat Transfer understands the needs of the process industry. That’s why our team is dedicated to producing Yuba® Shell & Tube Heat Exchangers that exceed our customers’ requirements and deliver measurable performance. Highly experienced in performing thermal design using HTRI software, we design, manufacture, and test our heat exchangers according to ASME, TEMA, and API standards. Our mechanical design uses Compress and SPX Heat Transfer propriety software and auto cad, solid works, and Invensys for producing the GA, shop drawings and Bill of Materials. Because we specialize in fabricating equipment for nuclear power plants, we follow the highest quality standards from engineering to manufacturing to shipping the units to your job site.
Hemilok® Head Closure
Shell & Tube Heat Exchangers in cyclical use are subject to thermal and pressure loads of a magnitude not encountered during base-loaded continuous service. Therefore, high-pressure Heat Exchangers require special designs to prevent the high stresses prevalent in cylindrical channels in cyclical service. The design of the juncture between the tubesheet and a cylindrical barrel is especially critical since the tubesheet changes temperature at a much greater rate than the cylindrical barrel.
Recognizing the need for a full access head capable of withstanding the demands of thermal shock during high cyclical use, our engineers created the Hemilok® Head Closure, an innovation so unique that it was granted a United States Patent in 1989.
Our design employs an internal spherical shape that is stronger than a cylinder and has lower mass to minimize the temperature difference that causes high stresses between the tubesheet and the cylindrical barrel. The design provides a large radius at this junction to prevent stress magnification without a corresponding increase in the outside diameter and the mass of the barrel. Hemilok® technology prevents the large stresses inherent in previous designs for base-loaded units and provides the fatigue life required for cycling and load-following units.
Our Hemilok® design provides full access for maintenance and employs shear keys to take the large hydraulic end load. The shear keys, which are also specially shaped to prevent fatigue cracks, minimize bolting in the gasketed design and reduce component weights for ease in opening and closing.
Hemilok® assures fatigue-free operation in difficult service. It provides additional space for ease of full access maintenance, which is especially applicable in channel sizes below 48” inside diameter. Hemilok® is available in all sizes and all high-pressure applications, including supercritical applications with design pressures over 5000 psi.
Contact our experienced team of professionals today to discuss your specific needs for Shell & Tube Heat Exchangers. We’re here to help!