1. Open up the purifier and place the blind disc at the bottom of disc stack. 2. The water outlet is blocked by seal on the gravity disc. 3. Blank off sealing water inlet line .
Wire drawing effect : It is erosion or scoring of valve seat and disc material of the valve . Causes : 1. Due to differential pressure across the valve . 2. Thermal and mechanical damages . Effects : Valve is unable to isolate the line and fails in sealing . Gas and liquid will leak from the wire and scratch like groove .
Attemperator are fitted in order to keep the steam temperature in the final stages of the superheater within certain desired limits . This is done for two main reasons . 1. The most important is the protection of the superheater tube material from the effects of overheating. *Mild steel superheater tubes tubes should not be subjected to steam temperatures in excess of 455℃. 2. The formation of bonded deposits on superheater tubes can be reduced if steam and gas streams within certain temperature ranges are prevented from coming into contact of each other. De-Superheater is used to reduce the temperature of a quantity of superheated steam and make it suitable for used in auxiliary services requires low temperature or saturated steam . *The reason for doing this way rather than by taking the saturated steam direct from steam drum , is to protect the superheater , these must be protected against overheating under all conditions of load by circulating steam through them . *Al...
Comments
Post a Comment