CN213516505U

CN213516505U - Boiler porous coal powder sampling gun

Info

Publication number: CN213516505U
Application number: CN202022433043.2U
Authority: CN
Inventors: 冷杰; 韩德斌; 丛日成; 王湛; 张涛; 付钰惠; 梁明文; 潘大勇; 张振杰; 刘学增; 宋金礼; 关风一; 于湛铭; 刘娟; 李含琼; 赵阳; 王博
Original assignee: Liaoning Dongke Electric Power Co Ltd
Current assignee: Liaoning Dongke Electric Power Co Ltd
Priority date: 2020-10-28
Filing date: 2020-10-28
Publication date: 2021-06-22
Anticipated expiration: 2030-10-28

Abstract

The utility model discloses a boiler porous coal powder sampling gun, wherein a sampling hole is arranged on the sampling gun, a conical plug is arranged at the gun head of the sampling gun, and a positioning indicator needle is arranged on the outer wall of the sampling gun; a sampling pulverized coal pushing device is arranged in the sampling gun; and a coal dust leakage prevention device is arranged in the sampling hole. Through the implementation of the device, the problems of long sampling time and complex rotary sampling system of the conventional single-hole pulverized coal can be effectively solved. Through the porous coal dust sampling pipe, coal dust sampling can be performed representatively. The porous coal dust sampling tube is simple and practical. The coal powder sampling operation is simple, the sampling is convenient, the sampling position is not required to be calibrated in advance, and the coal powder sampling representativeness is strong. The baffle is arranged at the sampling hole of the porous coal powder sampling gun, so that the coal powder in the pipeline can push the baffle to enter the sampling gun through the forward wind pressure. And through the setting of spring, prevent that the buggy that has gathered from flowing backward the sampling gun, reached the effect of maintaining the sampling result.

Description

Boiler porous coal powder sampling gun

Technical Field

The utility model relates to a boiler buggy sample technical field specifically is a buggy sampling rifle and thief hole design method that is used for different diameters to send whitewashed pipeline.

Background

The proper pulverized coal fineness control is a basic requirement for ensuring safe and stable combustion of the pulverized coal boiler, and influences the safety, the economy and the environmental protection of the pulverized coal boiler.

The coal powder fineness is measured by taking coal powder samples, the fineness of the coal powder ground by the coal mill and the quality of the coal powder entering each combustor are determined by taking the coal powder samples, the operation condition of a coal pulverizing system is monitored, and the performance diagnosis of the coal mill can be carried out.

Fineness of coal powder R₉₀And its homogeneity index n has a significant impact on boiler combustion. The pulverized coal is fine and easy to burn out, the more coarse particles in the pulverized coal are, the poor burnout performance is achieved, the combustion efficiency is low, and flame is easy to generate to flush the water-cooled wall. The burning of the pulverized coal is roughly delayed, and the center of the flame moves upwards. The surface temperature of the coarse particles is higher than that of the fine particles, and slagging is easily caused.

The fineness of the pulverized coal is a main factor influencing the economical efficiency of the boiler. Generally, the finer the pulverized coal is, the smaller the heat loss of the incompletely combusted boiler solid is, and the larger the power consumption of the pulverizing system is. The coarser the coal powder, the greater the heat loss due to incomplete combustion of the boiler solid, but the power consumption of the pulverizing system is correspondingly reduced. Therefore, an optimum coal fines fineness adjustment test should be performed.

The fineness of the pulverized coal affects the service life of the grinding roller of the coal mill. The fineness of the pulverized coal is adjusted by changing the opening of a deflecting opening of the separator or dynamically rotating the separator. The fineness of the coal powder can be changed by changing the primary air quantity.

DL/T466-2017 type selection guide rule of power station coal mill and pulverizing system makes the following requirements for coal powder fineness: as the pulverized coal becomes finer, the power consumption of the coal mill increases and the boiler combustion efficiency increases, so there is an economical pulverized coal fineness. The selection of the fineness of the economic pulverized coal mainly takes the following three factors into consideration: (1) the combustion characteristics of the coal. The coal with high volatile component, low ash content and high heat productivity has good combustion performance, and the pulverized coal is thin and can be thickened. (2) Combustion mode, heat intensity of the hearth and size of the hearth. The heat intensity of the hearth is high, and the fineness of the pulverized coal can be increased when the hearth is large. (3) The uniformity of the coal powder is good, and the fineness of the coal powder can be increased.

Therefore, in order to measure the fineness of the pulverized coal, it is very important to select an appropriate pulverized coal sampling tube and reasonably sample the pulverized coal.

DL/T567.2-2018 part 2 of Fuel test method for thermal Power plants: the method for taking and preparing coal powder samples in a furnace provides 3 coal powder sampling tubes. The first is a flat-head coal powder constant-speed sampling tube; secondly, the elbow type coal dust constant-speed sampling tube; and thirdly, a multi-head manual rotary sampling tube. The external diameter of the flat-head coal powder constant-speed sampling tube is 25mm, the sampling hole is 8mm, and the elbow coal powder constant-speed sampling tube is 10 mm. The static pressure zero constant-speed sampling tubes are compensation type static pressure zero constant-speed sampling tubes, but the arrangement of static pressure measurement is unreasonable, and the measurement accuracy is influenced. The flat-head coal powder constant-speed sampling tube samples coal powder on a primary air coal powder pipeline of the direct-fired pulverizing system, and the flat-head coal powder constant-speed sampling tube and the primary air coal powder pipeline can be matched with a sealing tube seat to sample coal powder. And the elbow formula buggy constant speed sampling tube buggy sample on the wind buggy pipeline of directly blowing formula powder process system, need use the short tube seat to carry out the buggy sample. The flat-head coal powder constant-speed sampling tube and the elbow coal powder constant-speed sampling tube are both single-hole coal powder sampling, the sampling points of the sampling tubes are required to be divided according to an equal ring area method, the position and time of each sampling point are not easy to control, the coal powder sampling time is long, and the coal powder sampling tube is easy to block. The multi-head manual rotation type sampling tube consists of a sampling tube, a positioning pin, an automatic rotation driving device, a tube seat, a sampling arm and the like. During sampling, the automatic rotation driving device drives the transmission shaft to rotate, the transmission shaft transmits rotating torque to the rotating shaft of the sampling arm through the herringbone ratchet mechanism, the sampling arm is driven to rotate, so that the 4 sampling heads rotate at a certain rotating speed on a plane perpendicular to the cross section of the pipeline, and continuous sampling is performed on 4 concentric circles with different radiuses. The multi-head manual rotation type sampling tube needs the size of a sampling arm to be matched with the diameter of a circular pulverized coal pipeline, and a sampling point can be selected only on a vertical pulverized coal pipeline and cannot be selected on a horizontal pulverized coal pipeline. The sampling tube has a rotating shaft, and a specially-made sampling hole tube seat is required to be configured, and the threads on the tube seat are matched with the plug and the sampling gun. The requirement on the roundness of a pulverized coal pipeline at a sampling position is strict, the sampling pipe is provided with 4 sampling holes with the diameter of 5mm, the sampling point positions are divided according to the pulverized coal pipeline diameter by an equal ring area method, the head of a sampling gun can deviate from the central axis of the pipeline, a multi-head sampling gun is provided with a sliding part and a rotating part, the sampling head is easy to damage, the system can leak, the sampling accuracy of pulverized coal is influenced, the system is complex, and the equipment is high in price.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a porous buggy sampling rifle of boiler to realize carrying out the effect of multiple spot buggy sample simultaneously, shortened the required time of buggy sample.

In order to achieve the above object, the utility model provides a following technical scheme: a boiler multi-hole pulverized coal sampling gun is characterized in that a sampling hole is formed in the sampling gun, a conical plug is arranged at the head of the sampling gun, and a positioning indicator needle is arranged on the outer wall of the sampling gun; a sampling pulverized coal pushing device is arranged in the sampling gun; and a coal dust leakage prevention device is arranged in the sampling hole.

Preferably, the device for preventing the pulverized coal from leaking is provided with a pair of baffles, the baffles are symmetrically hinged in the sampling hole, and the baffles are connected through a spring.

Preferably, one side of each of the pair of baffles is provided with a spring groove, and the springs are arranged in the spring grooves; and a limit stop is arranged on the other side of the pair of baffles and is attached to the inner wall of the sampling gun.

Preferably, the inner wall of the sampling gun is provided with a stop block groove, and the limit stop is arranged in the stop block groove.

Preferably, the sampling pulverized coal pushing device comprises a rotating rod arranged on the conical plug, an axial blade is arranged outside the rotating rod, and the axial blade is attached to the inner wall of the sampling gun; the rotating rod is driven by a motor.

Compared with the prior art, the beneficial effects of the utility model are that:

the baffle is arranged at the sampling hole of the porous coal powder sampling gun, so that the coal powder in the pipeline can push the baffle to enter the sampling gun through the forward wind pressure. And through the setting of spring, prevent that the buggy that has gathered from flowing backward the sampling gun, reached the effect of maintaining the sampling result.

Through setting up the axial blade in the sampling gun, the rotatory in-process of axial blade carries the buggy that has gathered in the sampling gun to follow-up buggy separator department, has further guaranteed the accuracy of sampling structure.

Drawings

Fig. 1 is the utility model discloses the sampling gun schematic diagram of the porous buggy sampling gun of boiler.

Fig. 2 is a sectional view of the utility model of a sampling gun for sampling porous coal powder in a boiler.

Fig. 3 is a schematic diagram of the sampling hole of the multi-hole pulverized coal sampling gun of the utility model.

Fig. 4 is the interior schematic view of the baffle of the porous pulverized coal sampling gun of the boiler of the utility model.

Fig. 5 is the outer schematic view of the baffle of the porous pulverized coal sampling gun of the boiler of the utility model.

FIG. 6 is a schematic diagram of concentric rings of the design method of the multi-hole pulverized coal sampling gun for a boiler of the present invention.

FIG. 7 is a schematic diagram of concentric rings of the design method of the multi-hole pulverized coal sampling gun for a boiler of the present invention.

1. Conical plugging; 2. a sampling gun; 3. a sampling hole; 4. positioning the pointer; 5. a baffle plate; 6. a spring; 7. a spring slot; 8. a limit stop block; 9. a block groove; 10. a rotating rod; 11. an axial vane.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Referring to fig. 1-5, the present invention provides a technical solution: a sampling hole 3 is formed in a sampling gun 2, the diameter of the sampling hole 3 is larger than 3 times of the maximum coal powder particle size, so that a collected sample is representative, the sampling gun is prevented from being blocked, and the diameter of the sampling hole 3 is 4-6 mm. A conical plug 1 is arranged at the gun head of the sampling gun 2, and a positioning indicator needle 4 is arranged on the outer wall of the sampling gun 2 to display the placement position of the sampling gun 2; a sampling coal powder pushing device is arranged in the sampling gun 2, so that coal powder which is sampled in the sampling gun 2 is pushed to an outlet, the subsequent coal powder separation is convenient, and the collected coal powder is prevented from reversely flowing out; the sampling hole 3 is internally provided with a device for preventing coal dust from leaking out, so that the collecting effect of the collected coal dust is further ensured.

The device for preventing the coal dust from leaking is provided with a pair of baffles 5, and the pair of baffles 5 are symmetrically hinged in the sampling hole 3, so that the pair of baffles 5 can completely seal the sampling hole 3 and can also complete the opening of the sampling hole 3 after rotation. A pair of baffle 5 is connected through spring 6 within a definite time, and spring 6 is under balanced state, and sampling hole 3 is sheltered from completely to a pair of baffle 5, when the buggy pipeline that sampling gun 2 located exists the malleation, will promote a pair of baffle 5 rotatory for the buggy normally enters into sampling gun 2 in, thereby guarantees the save effect of sampling gun 2 to the buggy of gathering.

One side of each baffle 5 is provided with a spring groove 7, and the springs 6 are arranged in the spring grooves 7, so that the direct influence of the airflow of the pulverized coal pipeline on the springs 6 is reduced; the opposite side of a pair of baffle 5 is provided with limit stop 8, and limit stop 8 laminates with the inner wall of sampling gun 2 mutually, avoids baffle 5 reverse rotation's problem to appear. The inner wall of the sampling gun 2 is provided with a stop groove 9, and the limit stop 8 is arranged in the stop groove 9, so that the possibility that the axial blade 11 collides with the limit stop 8 when rotating is reduced.

The sampling pulverized coal pushing device comprises a rotating rod 10 arranged on the conical plug 1, an axial blade 11 is arranged outside the rotating rod 10, and the axial blade 11 is attached to the inner wall of the sampling gun 2; the turning bar 10 is driven by a motor. Like this will drive axial blade 11 and rotate at the pivoted in-process of bull stick 10 to the buggy that promotes collection in the sampling gun 2 will be pushed out sampling gun 2 gradually, conveniently accomplishes subsequent separation work.

Referring to fig. 6-7, the present invention further provides a design method of a boiler multi-hole pulverized coal sampling gun, wherein the sampling gun 2 is installed at the upstream side of the powder feeding pipeline, and the length of the straight pipe section away from the local resistance element is not less than 10 times of the diameter of the powder feeding pipeline, and the resistance element comprises an elbow, a contraction pipe, a diffusion pipe, a baffle plate, etc. The length of the downstream side straight pipe section is not less than 3 times of the diameter of the powder feeding pipeline; when the above conditions are met, 1 sampling hole or 2 sampling holes which are 90 degrees to each other are arranged on the same annular section, and if the above conditions are not met, 3 sampling holes which are 120 degrees to each other are arranged on the same annular section.

The diameter D of the circular section and the number N of the divided rings are as follows:

when D is less than or equal to 325mm, N is 3; when D is more than 325mm and less than or equal to 426mm, N is 4; when D is more than 426mm and less than or equal to 630mm, N is 5; when D is more than 630mm and less than or equal to 820mm, N is 6.

The method for dividing the circular section grid type equal area comprises the following representative points:

dividing the circular section into N concentric rings with equal area, and dividing each ring into two or four parts with equal area by using the diameter or the diameter vertical to each other; the measuring point is positioned on the boundary line of the two divided concentric rings (as shown in FIG. 6); the position of the measuring point from the center of the circular section is obtained according to the formula (1):

in the formula:

r_i-the distance of the measuring point from the centre of the circular cross-section, in mm;

r-radius of circular section, mm;

i is the measuring point sequence number counted from the center of the circular section;

n is the number of equal area rings required to be divided by the circular section.

The specifications of the commonly used powder feeding pipeline are shown in table 1.

TABLE 1 common specification of powder feeding pipe

As can be seen from Table 2: theoretically speaking, the multipoint pulverized coal sampling gun needs 12 specifications, but the diameter specification of the powder feeding pipeline is larger and larger along with the increase of the boiler capacity, and the multipoint pulverized coal sampling gun needs 5-6 specifications to meet the pulverized coal sampling requirement.

The working principle is as follows: the multipoint boiler coal powder sampling gun is a coal powder sampling tube designed based on the average constant speed coal powder sampling principle, different sampling tubes are processed according to the diameters of different coal powder pipelines by an equal ring area method, the sampling position of the sampling gun is not required to be divided on site, and the sampling point can be selected on a vertical coal powder pipeline and also can be selected on a horizontal coal powder pipeline. And multi-point coal powder sampling can be simultaneously carried out, and the coal powder sampling time is short.

The arrangement method of the sampling holes during coal dust constant-speed sampling is to perform coal dust sampling according to an equal ring area method, divide the circular section of the sampling gun 2 into n concentric rings with equal areas, and locate the sampling points on the boundary line of each concentric ring. After arranging sampling gun 2 in sending the powder pipeline in whole, send the air current that carries the buggy in the powder pipeline to normally flow, realize the sample through seting up the sampling hole 3 that the position is different, gaseous will promote baffle 5 and accomplish rotatoryly to carry the buggy and enter into in the sampling gun 2. After the air current finishes, baffle 5 accomplishes through the elastic effect of spring 6 and resets to guarantee that the buggy can not backward flow. When the buggy was sampled, motor drive axial blade 11 accomplished rotatoryly, and the buggy in the sampling gun 2 will be continuous like this is pushed out by axial blade 11 to the buggy separator department of being connected with sampling gun 2, guarantees the collection effect to the buggy to avoid influencing the problem emergence of testing result.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a porous buggy sampling gun of boiler, thief hole (3), its characterized in that have been seted up on thief gun (2): a conical plug (1) is arranged at the gun head of the sampling gun (2), and a positioning indicator needle (4) is arranged on the outer wall of the sampling gun (2); a sampling pulverized coal pushing device is arranged in the sampling gun (2); and a device for preventing coal dust from leaking out is arranged in the sampling hole (3).

2. The boiler multi-hole pulverized coal sampling gun according to claim 1, characterized in that: the device for preventing the coal dust from leaking out is provided with a pair of baffle plates (5), the baffle plates (5) are symmetrically hinged in the sampling hole (3), and the baffle plates (5) are connected through a spring (6).

3. The boiler multi-hole pulverized coal sampling gun according to claim 2, characterized in that: one side of each baffle (5) is provided with a spring groove (7), and the springs (6) are arranged in the spring grooves (7); and a limit stop (8) is arranged on the other side of the pair of baffles (5), and the limit stop (8) is attached to the inner wall of the sampling gun (2).

4. The boiler multi-hole pulverized coal sampling gun according to claim 3, characterized in that: the inner wall of the sampling gun (2) is provided with a stop block groove (9), and the limit stop (8) is arranged in the stop block groove (9).

5. The boiler multi-hole pulverized coal sampling gun according to claim 1, characterized in that: the sampling pulverized coal pushing device comprises a rotating rod (10) arranged on the conical plug (1), an axial blade (11) is arranged outside the rotating rod (10), and the axial blade (11) is attached to the inner wall of the sampling gun (2); the rotating rod (10) is driven by a motor.