The 60Q00 Series main steam trap is suitable for controlling high temperature and high pressure saturated water in the drain systems of main steam and reheat steam pipes in thermal power plants. The tandem type fluid channel is continuously changing the fluid direction, so that fluid velocity is controlled at about 30m/s and cavitation damage is avoided. The throttling part is separable from the sealing face to effectively protect the sealing face. The trim surface is subjected to hardening treatment, reaching a hardness of about HRC70. It is featured by good erosion resistance and long service life. The main steam trap can be pneumatically or electrically controlled.