Abstract: WC-Co cemented carbide is the main material for manufacturing fixed throttle valve spool. The high-pressure natural gas carries the impurity particles at the bottom of the well during the throttling and depressurization process, which causes erosion damage to the core part of the throttle valve spool. To this end, a WC-Co cemented carbide grade YG15 was used of the target material in the study, and an indoor erosion test platform was constructed to determine the erosion model of YG15 cemented carbide and to verify it with simulation. The erosion model was further applied to the fixed throttle valve erosion simulation to predict the service life of the fixed throttle valve spool. The results show that the impact angle function of YG15 cemented carbide and the velocity index at 90°impact angle is 2.48; the erosion wear of YG15 cemented carbide increases from 847.1 mg to 1 235.6 mg when the erosion angle increases from 30°to 90°. The most serious throttle erosion is located at the throttle hole, and the erosion wear rate increases with the increase of particle mass flow rate; the life prediction of fixed throttle valve is that the throttle valve fixed nozzle should be replaced once half a year when the particle mass flow rate is small, and once a year when the particle mass flow rate is large.

Key words: WC-Co cemented carbide, erosion wear, fixed throttle valve, life prediction, fixed nozzle