The invention relates to a circular plate bimetallic type steam drain valve featuring large drainage capacity. The valve is characterized in that an inner cavity of a valve body (11) is provided with a filtering net (12), the centers of a water inlet hole (24) and an a water outlet hole (25) respectively at the left side and right side of the valve body (11) is on the same axis, screw holes (26) are evenly distributed at the bottom part of the inner cavity of the valve body (11) to communicate with the water outlet hole (25). Positioning pins (4) are symmetrically arranged at the upper part of the valve body (11) to position with a valve cover (2), a screw bolt (17) is used to tighten the positioning pins (4) and the valve cover (2); the valve cover (2) is connected with a valve bonnet (21) by a
screw thread. A
small head end of a
valve seat (8) is connected with the screw holes, the outer
diameter of the
valve seat (8) is sheathed with a spring (7), the inner cavity is provided with a support (6), the support (6) is internally provided with a core sleeve (5), the core sleeve (5) is internally provided with a core shaft (3), the core shaft (3) is provided with a
bimetallic strip group (14) which is positioned by an E-shaped clamp spring (13), an adjusting bolt (20) is connected with the valve cover (2) in thread. The steam drain valve of the invention features high operation reliability, contribution to
recovery of
condensed water,
elimination of air blocking and steam locking, agile and reliable movement,
low noise, long service life, convenient horizontal installation and easy maintenance.