If necessary, re-adjust the screw of the gland to set the gland pressure to adjust the cooling water volume synchronously.

The analysis indicates that there is a cold spot in the heat pump jacket of the melt pump body or the gas phase pipeline of the reaction kettle, so that a small amount of solidified small pieces appear in the contact area of ​​the pump body or the cold spot of the kettle body, forming a high crystalline polymer into the pump, so that The gears cannot mesh properly and cause pinching, which causes the coupling to trip.

The technical improvement measures adopted have proposed the following countermeasures through comprehensive analysis of previous accidents. Maintain normal melt leakage to control gland pressure and maintain proper leakage. The corrected gland pressure is recalculated according to the fluctuation range of the outlet pressure in actual production. The melt return flow rate is controlled by adjusting the needle valve opening degree, and the sealing cooling water quantity is synchronously adjusted according to the outlet pressure to ensure that the melt leakage amount is 100500 g/d. If necessary, the screw setting pressure of the gland is re-adjusted, and the gland is pressed. The pressure is controlled at 1 MPa under low load conditions and at about 1.5 MPa under high load conditions.

When operating the melt pump, low speed start (5%) is required, and the speed is increased and the speed is reduced by 0.5%. The outlet pressure of the control pump is lower than the design pressure to reduce the influence of the outlet pressure on the leakage. In addition, the specification of the melt filter operating procedures, appropriate increase of the switching standard, so that the melt pump outlet pressure is stable at 16.516.8MPa, also plays a role in the safe operation of the melt pump.