John Crane introduces the Type 8628VL mechanical seal for ethane and ethylene pipelines, where pressure and temperature change continuously during transportation. The article provides information announced by the company and technical context for better understanding.
The fluid in the pipeline can change phase between liquid, gas, and supercritical states. When the pressure decreases or the temperature increases, the fluid can evaporate right at the seal face, causing the sealing membrane to lose stability and often damaging conventional seals.
Contact or cartridge seals rely on a liquid film for lubrication. When the liquid evaporates, the film becomes thinner or disappears, and the seal face becomes dry and hot quickly. Non-contact seals use grooves to create a lifting force, so they are less dependent on the phase of the fluid.
According to the manufacturer, the seal uses non-contact spiral groove technology with two pairs of seal faces arranged in a tandem configuration. The company's technical director emphasizes that, unlike cartridge or contact seals, this design maintains a non-contact state even when the fluid changes phase quickly. The company claims that the solution increases reliability, operating efficiency, and environmental compliance.
The Machine Maker, PR Newswire. The article was compiled and reinterpreted by SNS-VN; brand names belong to their owners.