RU2038384C1 - Method of regulation of blow discharge entering blast furnace - Google Patents

Abstract

FIELD: foundry engineering. SUBSTANCE: when air-heater starts filling up signal for forced opening of release valve appears. After release valve tongue gets out of idling motion, signal calls for valve opening cessation. Simultaneously another signal calls for short time increase of blow discharge by means of acceleration of air-blowing unit and switching over pressure regulator for control of release valve position. It increases safety of working system and blow pressure accuracy. EFFECT: enhanced efficiency. 4 dwg

Description

 The invention relates to ferrous metallurgy and can be used in blast furnace production.

 A known method of controlling the flow of blast according to the application N 4887605/02, class. C 21 B 7/24 of December 4, 1990, which allows you to adjust the flow of blast at the time of filling the air heaters, but does not provide high reliability of the device. The disadvantage of this method is that the acceleration of the blower unit and the switching of the regulator to control the cold blast gate is done by pressing the button to fill the air heaters by the operator. During periodic operation of the circuit on each heater (approximately once every four hours), information on the readiness of all circuit elements for the next cycle of work in the known method is not available, and if one of the circuit elements fails, the acceleration of the blower unit can cause serious malfunctions in the blast furnace ovens.

 To ensure density, the tongue of the bypass valve overlaps the filling window (idle) by a certain amount; at the first moment of movement of the valve tongue until the idle is completely selected, no air is blown into the air heaters, while the acceleration of the blower unit has already begun. This can lead to over-pressure of the cold blast, adversely affect the reliability of the blower unit.

 When a signal is supplied to fill the air heaters, a signal is sent to force the bypass valve to open, and after the language of this valve exits to the position corresponding to the moment the filling window was opened (idle, for example, from the limit switch), a signal is generated to remove the forced opening of the bypass valve from the latter’s drive, with further operations according to the known method (switching the pressure regulator to the bypass valve actuator, acceleration of the blower unit, etc.).

 If the bypass valve actuator or its control lines are faulty, there will be no signal to perform further operations. If there is no signal for a predetermined time, a signal is sent to the operator’s shield about the inoperability of the bypass valve actuator on this heater.

 Given the inertia of the movement of the tongue of the bypass valve, the signal about the passage of the idle tongue is given with a lead, which is determined experimentally for each valve separately.

 In FIG. 1 shows a diagram of a bypass valve with a filling window, where: 1 filling window; 2 language bypass valve; 3 way switch; 4 (NC) limit switch contact; in FIG. 2 is an electrical diagram of the implementation of the proposed method, where 5 is a button for supplying a signal to fill the air heater; 6 relay repeater fill command; 7 switch to fully open the fill window; 8 (NO) relay contact 6; 9 bypass actuator actuator; 10 (NC) contact of the limit switch (Fig. 1, position 3); 11 (NO) relay contact (Fig. 3); 12 (NO) contact of the relay of the repeater of the output signal of the regulator to open the bypass valve; 13 (NO) contact of the idle trip switch (X.X); 14 command relay for switching the regulator to the bypass valve actuator (key 12), switching the regulator parameters; software acceleration of the blower; 15 (NO) relay contact 14; 16 (NO) relay contact 6.

 The method is as follows.

 When button 1 is pressed to fill the air heater (Fig. 2), the relay 6 circuit is assembled (the circuit will be destroyed only when the filling window 1 (Fig. 1) is fully opened by opening (NC) contact 4 of the travel switch, (NO) contact 4 of relay 6 puts the circuit for self-locking (NO) by contact 11 of relay 6 to assemble a circuit (Fig. 3) to close the control contactor of the bypass valve actuator in the opening direction.When the idle trip switch (P.V. X. X) is activated, contact 10 (NC) breaks the circuit contactor control, after which contactor control during The heater heater can only be filled with (NO) terminal 12 of the regulator's output repeater relay in the direction of opening the bypass valve. bypass valve actuator by contact 12 of the relay, switching the regulator parameters, (NO) by contact 15 of the relay put this circuit on self-locking.

 After the filling window is fully opened by opening contact 4 (Fig. 1), the circuits break up (Figs. 2-4).

 The application of the proposed method to improve the reliability of the control system for the flow of blast when transferring air heaters from the "Heating" to the operating mode, the accuracy of controlling the pressure of the blast will increase. This will reduce coke consumption and increase furnace productivity.

Claims (1)

 METHOD FOR REGULATING THE BLOW FLOW COMING TO THE DOMAIN FURNACE, mainly when the air heaters are switched from the heating mode to the operating mode and the air heaters are connected through the bypass valves with the cold blast collector, which includes a short-term increase in the flow rate of the blast supplied to the blower by the blower, and the recovery of the original blower blower , regulating the pressure on the bypass valve, characterized in that according to the signal about the start of filling the heater carried rd forced opening of the overflow valve by a signal on the output language bypass valve beyond idle while supplying the signal to the zoom magnification blast flow and pressure control switch to control the position of the bypass valve.

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