Development of High-Pressure PEEK Sealed Insulated Electrode Feedthroughs

With the continuous development of new energy and high-temperature materials, the closed-cycle turbine generator is changing to the direction of high power density and small volume design, and the electrode feedthroughs, as the key lead-in device connecting the internal and external equipment of the power plant, can no longer satisfy the requirements of the working conditions of the thermal power equipment due to the original complex structure, low operating temperature, and sealing pressure. In this paper, a compact electrode feedthrough with high sealing and insulating performance is developed, using polyether ether ketone (PEEK) as the sealing insulator and adopting the form of taper sealing. The effect of thread preload on the tapered sealing performance is investigated using finite element numerical analysis and hydrostatic testing. The results show that the PEEK insulating seal is subjected to the thread preload force to produce elastic-plastic deformation at the taper surface. Under the preload force of 25 kN, the electrode penetration has good sealing performance under the pressure condition of 15 MPa.