Time：2003/3
Model：AD6KS 、AD6MS
Size：6″
Norminal Pressure：300LB
Pressure Drop：0.5 M Pa
Shut-off Pressure：2.1 M Pa
Temperature：260℃

       In polymerization reaction, the pressure of 2.1 MPa in the tower is required to be ensured . When the single double - seat regulating valve is used , the trim is often pushed open and closed instantly at high pressure, which cannot achieve cut-off. Then changed to cage control valve to ensure shut off. When the pressure drop of 0.5 MPa in the tower is ensured , the polypropylene particles are blown out in the polymerization tower during the later stage of the polymerization , so that the cage regulating valve is blocked; In 2003 , we put forward that butterfly valve sealed by the large torque, with regulating and cutting off, can overcome the polypropylene particles and ensure the excellent sealing effect. As for the pressure drop of 0.5 MPa , the butterfly valve can be completely satisfied. After changing to ADQ butterfly valve, the operation is normal , and completely meet the process production requirements.