CN210709768U

CN210709768U - Automatic coal feeding power assisting device of weighing type metering coal feeder

Info

Publication number: CN210709768U
Application number: CN201921243745.5U
Authority: CN
Inventors: 张玉忠; 李宏岩; 李俊宏; 葛军; 胡文飞; 管玉保
Original assignee: Jilin Jichang Electric Power Co Ltd; Siping First Thermal Power Co Of Jilin Electric Power Co ltd
Current assignee: Jilin Jichang Electric Power Co Ltd; Siping First Thermal Power Co Of Jilin Electric Power Co ltd
Priority date: 2019-08-02
Filing date: 2019-08-02
Publication date: 2020-06-09
Anticipated expiration: 2029-08-02

Abstract

The utility model relates to a weighing type measures automatic booster unit of feeder coal feed, the device include a feedwell, the both sides of the lateral wall upper discharge gate of feedwell are fixed with two bearing frames and bearing, are provided with the helping hand axle on two bearing frames, inverter motor is connected through freewheel clutch and speed reducer to the one end of helping hand axle, the other end of helping hand axle has four bellied proximity switch response pieces along circumference cross, is fixed with proximity switch through the proximity switch support on the bearing frame, the mid portion H of helping hand axle is the reducing structure of outside-in symmetry, the broken tooth of annular has set gradually along axial outside-in on the mid portion H of helping hand axle. The utility model overcomes the shortcoming of current weighing type metering coal feeder has improved weighing type metering coal feeder's adaptability, has solved the stifled problem of the big coal cinder card of weighing type metering coal feeder feed inlet bottom.

Description

Automatic coal feeding power assisting device of weighing type metering coal feeder

Technical Field

The utility model relates to a coal fired thermal power factory coal feeding equipment field, specific weighing type measurement feeder coal feeding automatic power assisting device that says so.

Background art:

a weighing type metering coal feeder is a main coal feeding device for a boiler pulverizing system of a coal-fired thermal power plant. The coal feeding device can realize continuous and uniform coal feeding, accurately weigh and calculate in the coal feeding process, and automatically adjust the coal feeding amount according to the requirements of a boiler combustion control system, so that the actual coal feeding amount is matched with the boiler load, and the coal feeding device becomes the main coal feeding equipment of a coal-fired thermal power plant at present.

When the weighing type metering coal feeder works, coal enters the coal feeder from the coal storage bin through the coal inlet, is conveyed to the outlet of the coal feeder through the metering conveying rubber belt, and enters the coal mill through the coal outlet or directly enters the boiler hearth. Weighing carrier rollers with accurate intervals are arranged below the metering conveying rubber belt to form a weighing and metering span, and a metering carrier roller connected with a pair of high-precision weighing sensors is arranged in the middle of the weighing and metering span. When the coal is conveyed through the weighing span, the weighing sensor produces voltage signal proportional to the weight of coal on the rubber belt, the signal is amplified and AD converted and then sent to the calculation regulator in digital form, and the speed sensor is installed at the shaft end of the main driving motor to send the speed of the rubber belt to the calculation regulator in pulse signal form. The two signals are calculated by the calculation regulator to display the instantaneous coal feeding amount and the accumulated coal feeding amount of the weighing type metering coal feeder, the calculation regulator calculates the coal feeding amount and compares the coal feeding amount signal with a preset coal feeding amount signal or a coal feeding amount signal required by a boiler combustion control system, the speed of the motor which should run is obtained after the adjustment is carried out according to the deviation, and the conveying speed of the metering conveying rubber belt is changed by changing the rotating speed of the main motor, so that the actual coal feeding amount is the same as the required coal feeding amount, and the requirement of the boiler load is met.

However, the existing weighing type metering coal feeder has no coal feeding automatic power assisting device, when a coal hopper has large frozen coal or too large coal blocks, the bottom of a feed port of the coal feeder can be clamped, the normal operation of coal feeding of a boiler is influenced, and the normal operation of the coal feeder can be recovered only after the clamped coal blocks are manually removed.

The utility model has the following contents:

in order to overcome the shortcoming of current weighing type metering coal feeder and improve the adaptability of weighing type metering coal feeder, solve the stifled problem of big coal cinder card in weighing type metering coal feeder feed inlet bottom, the utility model provides a weighing type metering coal feeder gives coal automatic power assisting device.

The utility model aims at realizing the automatic power assisting device for coal feeding of the weighing type metering coal feeder, which comprises a feeding barrel, wherein a feeding hole is arranged above the axial direction of the feeding barrel, a discharging hole is arranged on the radial side wall of the feeding barrel, the opening direction of the discharging hole faces to the running direction of a belt of the coal feeder, two bearing seats are fixed on two sides of the discharging hole on the side wall of the feeding barrel, each bearing seat is provided with a bearing, two bearing seats are provided with a power assisting shaft, one end of the power assisting shaft is connected with a variable frequency motor through an overrunning clutch and a speed reducer, the other end of the power assisting shaft is provided with four convex proximity switch induction blocks in a crossed way along the circumferential direction, a proximity switch support is fixed on the bearing seat close to one side of the proximity switch induction blocks, a proximity switch is fixed on the proximity switch support, the proximity switch is arranged corresponding to the raised proximity switch induction block; the middle part H (the part between the two bearings) of the boosting shaft is of a diameter-changing structure which is symmetrical from outside to inside, the diameter of the middle part H is reduced from outside to inside, and annular crushing teeth are sequentially arranged on the middle part H from outside to inside along the axial direction.

The utility model has the advantages and the technical effect be:

1. the utility model discloses the device mainly is installed in the feed inlet exit of weighing type measurement feeder, and when weighing type measurement feeder feed inlet department was blocked by the bold coal, the entry bite can be monitored to the automatic booster unit of coal feeding to automatic processing.

2. The utility model discloses automatic booster unit's of coal feeding helping hand axle has crushing function through special shape design, under the frictional force effect of the belt of helping hand axle rolling force effect and former weighing type measurement feeder, accomplishes extrusion and breakage to the bold coal that exceeds standard, can have good crushing capacity to the coal cinder that raw coal size 1.2 times through experiment the device.

3. The utility model discloses the device simple structure, borrow the principle of coupling grinder for reference, can realize the breakage to super large coal cinder and frozen piece, this device has been at the experimental success of the first thermoelectric company of the four equal shares of ji electricity thigh.

4. The utility model also has the advantages of ① automated inspection inlet pipe jam and automatic processing, ② can be connected with the former coal breakage signal of feeder, high reliability, ③ helping hand axle through the optimal design, have good crushing effect, ④ can set for helping hand time by oneself, ⑤ has manual executive device, can artifical assistance-disposal inlet pipe department jam.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

FIG. 2 is a sectional view of the power assisting shaft A-A of FIG. 1 according to the present invention

Fig. 3 is a top view of fig. 1 according to the present invention.

Fig. 4 is a left side view of fig. 3 of the present invention.

Fig. 5 is a reference diagram of the usage state of the device of the present invention.

Fig. 6 is a control circuit diagram of the proximity switch of the present invention.

Fig. 7 is a logic judgment diagram of the DCS apparatus of the present invention.

Reference numerals: the device comprises a feed barrel 1, a feed inlet 1-1, a discharge outlet 1-2, a bearing seat 2, a bearing 3, a boosting shaft 4, a proximity switch induction block 4-1, annular crushing teeth 4-2, an overrunning clutch 5, a speed reducer 6, a variable frequency motor 7, a proximity switch bracket 8 and a proximity switch 9.

Detailed Description

Shown in fig. 1, 2, 3 and 4: an automatic coal feeding power assisting device of a weighing type metering coal feeder comprises a feeding barrel 1, wherein a feeding hole 1-1 is arranged axially above the feeding barrel 1, a discharging hole 1-2 is arranged on the radial side wall of the feeding barrel 1, the opening direction of the discharging hole 1-2 faces the running direction of a belt of the coal feeder, two bearing seats 2 are fixed on two sides of the discharging hole 1-2 on the side wall of the feeding barrel 1, a bearing 3 is arranged on each bearing seat 2, a power assisting shaft 4 is arranged on the two bearing seats 2, one end of the power assisting shaft 4 is connected with a variable frequency motor 7 through an overrunning clutch 5 and a speed reducer 6, the other end of the power assisting shaft 4 is provided with four convex proximity switch induction blocks 4-1 in a crossed mode along the circumferential direction, a proximity switch support 8 is fixed on the bearing seat 2 close to one side of the proximity switch induction blocks 4-1, a proximity switch 9 is fixed on the proximity switch bracket 8, and the proximity switch 9 is arranged corresponding to the raised proximity switch induction block 4-1; the middle part H (the part between the two bearings 3) of the assisting shaft 4 is of a diameter-changing structure which is symmetrical from outside to inside, the diameter of the diameter-changing structure is reduced from outside to inside, and annular crushing teeth 4-2 are sequentially arranged on the middle part H from outside to inside along the axial direction.

The working principle is as follows:

the working process of the coal feeding automatic power assisting device is as follows: coal hopper → feed inlet → power-assisted shaft → coal feeder belt → discharge outlet → coal pulverizer.

As shown in fig. 5: the coal feeding automatic power assisting device is arranged at a position 1-2 of a bottom discharge port of a coal feeding machine feeding barrel 1, a coal feeding machine belt carries falling coal at a feeding port 1-1 to move in a direction shown by an arrow to push a power assisting shaft 4 to rotate, when the coal is large to a certain degree, the power assisting shaft 4 is clamped by the coal to stop rotating, a proximity switch 9 does not send out a pulse signal indicating the rotation of a main shaft any more, a control loop is linked and interlocked to start a variable frequency motor 7 to operate according to set time, the variable frequency motor 7 drives the power assisting shaft 4 to rotate through a speed reducer 6 and an overrunning clutch 7, the overlarge coal is crushed through annular crushing teeth 4-2 on the power assisting shaft 4 and then passes through the discharge port 1-2 under the resultant force action of the coal feeding machine belt, the variable frequency motor 7 stops working when the set time is reached, the overrunning clutch 5 is disengaged, normal coal flow pushes the power assisting shaft 4 to rotate to drive four, and the control circuit is matched with the proximity switch 9 to output a pulse signal, and after detecting the pulse signal, the control circuit places the variable frequency motor 7 in a standby state to wait for the next cycle for processing the blockage of the large coal blocks.

As shown in fig. 1 and 2: the boosting shaft 4 is a core component of the coal feeding automatic boosting device, the boosting shaft 4 is made of high-strength high-wear-resistance alloy steel or cast carbon steel, and annular crushing teeth 2-1 are sequentially machined in the middle of the boosting shaft 4 from outside to inside along the axial direction.

The utility model discloses proximity switch control circuit and DCS logical principle are shown in figure 6, 7:

the proximity switch 9 is an alternating current 220V inductance type proximity switch (the model is Wis Niemann w415kcx in the example), the working power supply AC220V is taken from a coal feeder in-situ control cabinet, an intermediate relay 1ZJ (shown in figure 6) is additionally arranged in the control cabinet, and when the power-assisted shaft rotates, the proximity switch 9 detects that the induction block 4-1 excites the intermediate relay 1 ZJ. Normally open passive contact 1ZJ1 with the relay and send DCS system DI fastener as helping hand axle detected signal, compile the logic as shown in figure 7, helping hand axle detected signal frequently closes/breaks off during normal operating, then judge helping hand axle stall when detecting signal is closed or breaks off always in DCS system XX second (the example sets up to 7 seconds), send alarm information, simultaneously through DO card output signal to inverter motor, interlock start inverter motor broken coal cinder. After the variable frequency motor is started, the variable frequency motor is automatically stopped after the logic timer T(s) (the example is set to be 30 seconds).

The noun explains:

DCS is an English abbreviation (Distributed Control System) of a Distributed Control System, and is also called as a Distributed Control System in the domestic automatic Control industry. So-called distributed control systems, or in some cases distributed systems, are a new type of computer control system, compared to centralized control systems, which is developed and evolved on the basis of centralized control systems. The system is a multi-stage computer system which is composed of a process control stage and a process monitoring stage and takes a communication network as a link, integrates 4C technologies of computers, communication, display, control and the like, and has the basic ideas of decentralized control, centralized operation, hierarchical management, flexible configuration and convenient configuration. DCS is widely used in centralized control systems for power plants.

Variable frequency motor: the variable frequency speed regulating motor is called as variable frequency motor for short, is a general name of a motor driven by a frequency converter, and has the advantage of having a starting function; the resistance values of the stator and the rotor are reduced by adopting an electromagnetic design; the method is suitable for frequent speed change under different working conditions; energy is saved to a certain extent, the speed regulation scheme is the mainstream at present, and the method can be widely applied to stepless speed change transmission (vector frequency converters for example projects) in various industries.

Claims

1. The utility model provides a weighing type measurement feeder automatic power assisting device of coal feeding, the device includes a feedwell (1), its characterized in that: two bearing seats (2) are fixed on two sides of a discharge port (1-2) on the side wall of the feed barrel (1), a bearing (3) is arranged on each bearing seat (2), a boosting shaft (4) is arranged on the two bearing seats (2), one end of the boosting shaft (4) is connected with a variable frequency motor (7) through an overrunning clutch (5) and a speed reducer (6), the other end of the boosting shaft (4) is provided with four raised proximity switch induction blocks (4-1) in a circumferential cross manner, a proximity switch bracket (8) is fixed on the bearing seat (2) close to one side of the proximity switch induction block (4-1), a proximity switch (9) is fixed on the proximity switch bracket (8), and the proximity switch (9) is arranged corresponding to the raised proximity switch induction blocks (4-1); the middle part H of the assisting shaft (4) is of a symmetrical reducing structure from outside to inside, the diameter of the reducing structure from outside to inside is reduced from inside to outside, and annular crushing teeth (4-2) are sequentially arranged on the middle part H of the assisting shaft (4) from outside to inside along the axial direction.