Steam Supply System and Check Valve for Use Therein

A steam supply system wherein:

• a steam supply passage incorporates a pressure reducing valve and the passage further incorporates a steam ejector downstream of the pressure reducing valve;
• a suction portion of the steam ejector is connected to a re-evaporation tank for re-evaporating steam condensate via a suction passage;
• passage steam of the pressure reducing valve is used as a driving steam for the steam ejector;
• re-evaporated steam within the re-evaporation tank is suctioned by the steam ejector to be mixed with the passage steam:
• the suction passage incorporates a check valve for preventing reverse flow of steam to the re-evaporation tank;
• the valve opening ratio of the pressure reducing valve is adjusted in accordance with the temperature or pressure of passage steam past the pressure reducing valve;
• and
• the check valve has an inherent flow characteristics that an increase ratio of a flow rate associated with increase of its valve opening ratio is equivalent between a small opening ratio range with small valve opening ratios and a large opening ratio range with large valve opening ratios or an inherent flow characteristics that the increase ratio is smaller in the small opening ratio range than in the large opening ratio range.

A steam supply system wherein:

• a steam supply passage incorporates a pressure reducing valve and the passage further incorporates a steam ejector downstream of the pressure reducing valve;
• a suction portion of the steam ejector is connected to a re-evaporation tank for re-evaporating steam condensate via a suction passage;
• passage steam of the pressure reducing valve is used as a driving steam for the steam ejector;
• re-evaporated steam within the re-evaporation tank is suctioned by the steam ejector to be mixed with the passage steam:
• the suction passage incorporates a check valve for preventing reverse flow of steam to the re-evaporation tank;
• the valve opening ratio of the pressure reducing valve is adjusted in accordance with the temperature or pressure of the re-evaporated steam inside the re-evaporation tank;
• and
• the check valve has an inherent flow characteristics that an increase ratio of a flow rate associated with increase of its valve opening ratio is equivalent between a small opening ratio range with small valve opening ratios and a large opening ratio range with large valve opening ratios or an inherent flow characteristics that the increase ratio is smaller in the small opening ratio range than in the large opening ratio range.