A flame detector based on a single-chip microcomputer
By setting an observation hole and a sliding mechanism for a transparent observation plate on the flame detector, the problem of difficult observation in the high-temperature and high-dust environment of the waste incinerator is solved, and safe and reliable monitoring of the incineration status is achieved.
Patent Information
- Application Number
- CN202310279415.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-03-22
- Publication Date
- 2025-10-24
- Estimated Expiration
- 2043-03-22
AI Technical Summary
Existing flame detectors are difficult to effectively observe the combustion process in the high-temperature and high-dust environment of waste incinerators, posing a safety hazard.
Design a microcontroller-based flame detector. By setting an observation hole and a transparent observation plate on the detector housing, the transparent observation plate can be opened and closed in a controllable manner using a sliding rod, a locking rod and a spring mechanism, so as to facilitate the observation of the combustion situation.
It enables effective observation of the incineration process under high temperature and high dust conditions, avoids accidents, and ensures the safe operation of the waste incinerator.
Smart Images

Figure CN116293771B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of flame detector, and particularly relates to a flame detector based on single-chip microcomputer. BACKGROUND
[0002] As an important means of waste disposal, waste incineration for power generation is harmless, reduction and resource, and is more and more highly valued by governments. Some waste incineration power generation projects have emerged like mushrooms after a spring rain. The burner is an indispensable device for starting and igniting waste on the waste incinerator and auxiliary heating of the furnace body, and plays an important role in the normal operation of the waste incineration power generation system.
[0003] However, in order to ensure the normal combustion of waste and the complete decomposition of harmful substances (such as dioxin), the temperature in the furnace body needs to be maintained at (800-1000) DEG C at present. Therefore, compared with conventional incinerators, waste incinerators have the characteristics of high radiant temperature and large dust fly ash. As an important component for detecting flame of the burner, the flame detector plays a key role in the safety and normal operation of the burner. In view of the harsh environmental characteristics of high radiant temperature and large dust fly ash of the waste incinerator, it is necessary to observe at all times during the incineration process to avoid accidents. SUMMARY
[0004] The present application aims at solving the problems in the prior art and provides a flame detector based on single-chip microcomputer.
[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme:
[0006] A flame detector based on single-chip microcomputer, comprising a detector shell, a single-chip microcomputer is fixedly installed on the inner wall of the bottom of one side of the detector shell, an observation hole is formed on the inner wall of the side of the detector shell close to the single-chip microcomputer, a transparent observation plate is installed in the observation hole, cavities are formed in the top and bottom of the observation hole, a sliding hole is formed in the bottom inner wall of the cavity, a sliding rod is slidably installed in the sliding hole, one end of the sliding rod extends into the cavity, the other end of the sliding rod extends into the observation hole, the side of the sliding rod extending into the observation hole is in contact with one side of the transparent observation plate, a through hole is formed in the bottom inner wall of the cavity, a clamping rod is slidably installed in the through hole, one end of the clamping rod extends into the cavity, the other end of the clamping rod extends into the observation hole, the side of the clamping rod extending into the observation hole is in contact with one side of the transparent observation plate, one end of the clamping rod extending into the cavity is fixedly installed with a cross rod, one end of a short rod is fixedly installed on the top of the cross rod, and a first rotating shaft is rotatably installed on the other end of the short rod.
[0007] Preferably, one end of the first spring is fixedly installed on one side of the sliding rod, and the other end of the first spring is fixedly connected with the inner wall of one side of the cavity.
[0008] Preferably, a rotating hole is arranged on the inner wall of one side of the cavity, a second rotating shaft is rotatably arranged in the rotating hole, a rotating rod is fixedly arranged on the second rotating shaft, one end of the rotating rod extends into the cavity, the other end of the rotating rod extends out of the cavity, and the one end of the rotating rod extending into the cavity is fixedly connected with the first rotating shaft.
[0009] Preferably, one end of the second spring is fixedly arranged on the top of the rotating rod, and the other end of the second spring is fixedly connected with the top inner wall of the cavity.
[0010] Preferably, one end of the thick rod is fixedly arranged on the bottom inner wall of the observation hole, the other end of the thick rod is rotatably arranged with a rotating shaft, a baffle is fixedly arranged on the rotating shaft, a stopper is fixedly arranged on the top inner wall of the observation hole, one side of the stopper is in contact with one side of the baffle, a groove is arranged on the side of the detector shell close to the observation hole, one end of a thin rod is fixedly arranged on the top inner wall of the groove, the other end of the thin rod is rotatably arranged with a third rotating shaft, one end of an elongated rod is fixedly arranged on the third rotating shaft, and the other end of the elongated rod is in contact with one side of the baffle.
[0011] Preferably, a fixing hole is arranged on one side of the elongated rod, a sliding groove is arranged on the inner wall of one side of the groove, a fixing rod is slidably arranged in the sliding groove, the fixing rod has an L-shaped structure, one end of a third spring is fixedly arranged on the bottom of the fixing rod, the other end of the third spring is fixedly connected with the bottom inner wall of the sliding groove, and one end of the fixing rod passes through the fixing hole.
[0012] Preferably, a moving groove is arranged on the top of the fixing rod, a receiving groove is arranged on the top inner wall of the sliding groove, a limiting rod is slidably arranged in the moving groove, the top of the limiting rod extends into the receiving groove, one end of a fourth spring is fixedly arranged on one side of the limiting rod, the other end of the fourth spring is fixedly connected with the inner wall of one side of the moving groove, one end of a jacking rod is fixedly arranged on one side of the limiting rod, and the other end of the jacking rod is in contact with one side of the elongated rod.
[0013] Preferably, a fourth rotating shaft is rotatably arranged on the side of the elongated rod away from the sliding groove, a pull rod is fixedly arranged on the fourth rotating shaft, and the pull rod has an L-shaped structure; and a clamping groove is arranged on one side of the detector shell, and the clamping groove is matched with the rotating pull rod.
[0014] A use method of a flame detector based on a single-chip microcomputer, comprising the following steps:
[0015] S1 when it is needed to observe, first sliding the fixing rod downward, the fixing rod is separated from the fixing hole, at the same time, the fixing rod drives the moving groove and the limiting rod to move downward, and the limiting rod is separated from the receiving groove;
[0016] S2 then rotating the elongated rod, then rotating the baffle to open the observation hole, and then rotating the pull rod to make the pull rod clamped into the clamping groove;
[0017] S3 then rotates the rotating rod, the rotating rod drives the first rotating shaft to rotate and move upward, the first rotating shaft drives the short rod to move upward, the short rod drives the horizontal rod to move upward, the horizontal rod drives the clamping rod to move upward, and the clamping rod is retracted into the cavity;
[0018] S4 then clamps the transparent observation plate into the observation hole, then releases the rotating rod, the second spring drives the rotating rod to rotate, the rotating rod drives the first rotating shaft to rotate and move downward, the first rotating shaft drives the short rod to move downward, the short rod drives the horizontal rod to move downward, the horizontal rod drives the clamping rod to move downward, and then the clamping rod clamps the transparent observation plate, thereby achieving the observation purpose.
[0019] Compared with the prior art, the beneficial effects of the present application are:
[0020] In the present application, when observation is needed, first, the fixed rod is slid downward, the fixed rod is separated from the fixed hole, and at the same time, the fixed rod drives the moving groove and the limiting rod to move downward, the limiting rod is separated from the storage groove, then the long rod is rotated, then the baffle is rotated to open the observation hole, then the pull rod is rotated to clamp the pull rod into the clamping groove, then the rotating rod is rotated, the rotating rod drives the first rotating shaft to rotate and move upward, the first rotating shaft drives the short rod to move upward, the short rod drives the horizontal rod to move upward, the horizontal rod drives the clamping rod to move upward, and the clamping rod is retracted into the cavity, then the transparent observation plate is clamped into the observation hole, then the rotating rod is released, the second spring drives the rotating rod to rotate, the rotating rod drives the first rotating shaft to rotate and move downward, the first rotating shaft drives the short rod to move downward, the short rod drives the horizontal rod to move downward, the horizontal rod drives the clamping rod to move downward, and then the clamping rod clamps the transparent observation plate, thereby achieving the observation purpose;
[0021] The present application is provided with an observation hole on one side of the detector shell, which can effectively observe the burning condition during burning, and avoids accidents during burning. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 It is a front structure schematic view of a flame detector based on a single-chip microcomputer proposed in the present application;
[0023] Figure 2 It is a structure schematic view of part A of a flame detector based on a single-chip microcomputer proposed in the present application;
[0024] Figure 3 It is a structure schematic view of part B of a flame detector based on a single-chip microcomputer proposed in the present application;
[0025] Figure 4 It is a structure schematic view of part C of a flame detector based on a single-chip microcomputer proposed in the present application;
[0026] Figure 5A three-dimensional structural schematic view of a detector shell of a single-chip microcomputer-based flame detector is provided in the present application.
[0027] In the figure: 1 detector shell, 2 single-chip microcomputer, 3 observation hole, 4 transparent observation plate, 5 cavity, 6 sliding hole, 7 sliding rod, 8 through hole, 9 clamping rod, 10 crossbar, 11 short rod, 12 first rotating shaft, 13 rotating hole, 14 second rotating shaft, 15 rotating rod, 16 baffle, 17 stop block, 18 groove, 19 thin rod, 20 third rotating shaft, 21 long rod, 22 fixing hole, 23 sliding groove, 24 fixed rod, 25 moving groove, 26 limiting rod, 27 storage groove, 28 jacking rod, 29 fourth rotating shaft, 30 pull rod, 31 clamping groove. DETAILED DESCRIPTION
[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.
[0029] Embodiment one
[0030] Reference Figures 1-5 A single-chip microcomputer-based flame detector comprises a detector shell 1, a single-chip microcomputer 2 is fixedly welded on the inner wall of the bottom of one side of the detector shell 1, an observation hole 3 is chiseled on the inner wall of the side close to the single-chip microcomputer 2 of the detector shell 1, a transparent observation plate 4 is installed in the observation hole 3, cavities 5 are chiseled on the top and bottom of the observation hole 3, a sliding hole 6 is chiseled on the inner wall of the bottom of the cavity 5, a sliding rod 7 is slidingly installed in the sliding hole 6, one end of the sliding rod 7 extends into the cavity 5, the other end of the sliding rod 7 extends into the observation hole 3, the side of the sliding rod 7 extending into the observation hole 3 is in contact with one side of the transparent observation plate 4, a through hole 8 is chiseled on the inner wall of the bottom of the cavity 5, a clamping rod 9 is slidingly installed in the through hole 8, one end of the clamping rod 9 extends into the cavity 5, the other end of the clamping rod 9 extends into the observation hole 3, the side of the clamping rod 9 extending into the observation hole 3 is in contact with one side of the transparent observation plate 4, one end of the clamping rod 9 extending into the cavity 5 is fixedly welded with a crossbar 10, one end of a short rod 11 is fixedly welded on the top of the crossbar 10, and the other end of the short rod 11 is rotatably installed with a first rotating shaft 12.
[0031] In the present application, one end of a first spring is fixedly welded on one side of the sliding rod 7, and the other end of the first spring is fixedly connected with the inner wall of one side of the cavity 5.
[0032] In the present application, a rotating hole 13 is chiseled on the inner wall of one side of the cavity 5, a second rotating shaft 14 is rotatably installed in the rotating hole 13, a rotating rod 15 is fixedly welded on the second rotating shaft 14, one end of the rotating rod 15 extends into the cavity 5, the other end of the rotating rod 15 extends out of the cavity 5, and one end of the rotating rod 15 extending into the cavity 5 is fixedly connected with the first rotating shaft 12.
[0033] In the application, one end of the second spring is fixedly welded on the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0034] In the application, one end of the second spring is fixedly welded on the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0035] In the application, one end of the second spring is fixedly welded on the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0036] In the application, one end of the second spring is fixedly welded on the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0037] In the application, one end of the second spring is fixedly welded on the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0038] Example two
[0039] The application discloses a single-chip microcomputer-based flame detector which comprises a detector shell 1, a single-chip microcomputer 2 fixedly welded on the inner wall of the bottom of one side of the detector shell 1, an observation hole 3 chiseled on the inner wall of the side of the detector shell 1 close to the single-chip microcomputer 2, a transparent observation plate 4 installed in the observation hole 3, cavities 5 chiseled on the top and bottom of the observation hole 3, a sliding hole 6 chiseled on the inner wall of the bottom of the cavity 5, a sliding rod 7 slidingly installed in the sliding hole 6, one end of the sliding rod 7 extending into the cavity 5, the other end of the sliding rod 7 extending into the observation hole 3, the side of the sliding rod 7 extending into the observation hole 3 being in contact with the side of the transparent observation plate 4, a through hole 8 chiseled on the inner wall of the bottom of the cavity 5, a clamping rod 9 slidingly installed in the through hole 8, one end of the clamping rod 9 extending into the cavity 5, the other end of the clamping rod 9 extending into the observation hole 3, the side of the clamping rod 9 extending into the observation hole 3 being in contact with the side of the transparent observation plate 4, one end of the clamping rod 9 extending into the cavity 5 being fixedly welded with a horizontal rod 10, one end of a short rod 11 fixedly welded with the top of the horizontal rod 10, and a first rotating shaft 12 rotatably installed at the other end of the short rod 11, wherein the transparent observation plate 4 is used for observing the burning condition in the detector.
[0040] In the application, one end of the first spring is fixedly welded with the side of the sliding rod 7, and the other end of the first spring is fixedly connected with the inner wall of the side of the cavity 5.
[0041] In the application, a rotating hole 13 is chiseled on the inner wall of the side of the cavity 5, a second rotating shaft 14 is rotatably installed in the rotating hole 13, a rotating rod 15 is fixedly welded with the second rotating shaft 14, one end of the rotating rod 15 extends into the cavity 5, the other end of the rotating rod 15 extends out of the cavity 5, one end of the rotating rod 15 extending into the cavity 5 is fixedly connected with the first rotating shaft 12, and the rotating rod 15 is used for driving the clamping rod to move.
[0042] In the application, one end of the second spring is fixedly welded with the top of the rotating rod 15, and the other end of the second spring is fixedly connected with the inner wall of the top of the cavity 5.
[0043] In the application, one end of a thick rod is fixedly welded with the inner wall of the bottom of the observation hole 3, the other end of the thick rod is rotatably installed with a rotating shaft, a baffle 16 is fixedly welded with the rotating shaft, a stopper 17 is fixedly welded with the inner wall of the top of the observation hole 3, the side of the stopper 17 is in contact with the side of the baffle 16, a groove 18 is chiseled on the side of the detector shell 1 close to the observation hole 3, one end of a thin rod 19 is fixedly welded with the inner wall of the top of the groove 18, a third rotating shaft 20 is rotatably installed at the other end of the thin rod 19, one end of a long rod 21 is fixedly welded with the third rotating shaft 20, the other end of the long rod 21 is in contact with the side of the baffle 16, and the baffle 16 is used for shielding the observation hole.
[0044] In the present application, one side of the long rod 21 is chiseled with a fixing hole 22, the inner wall of one side of the groove 18 is chiseled with a sliding groove 23, the sliding groove 23 is slidably installed with a fixed rod 24, and the fixed rod 24 is in L-shaped structure, the bottom of the fixed rod 24 is fixedly welded with one end of a third spring, the other end of the third spring is fixedly connected with the bottom inner wall of the sliding groove 23, and one end of the fixed rod 24 penetrates through the fixing hole 22, and the fixed rod 24 is used for fixing the long rod.
[0045] In the present application, the top of the fixed rod 24 is chiseled with a moving groove 25, the top inner wall of the sliding groove 23 is chiseled with a receiving groove 27, the moving groove 25 is slidably installed with a limiting rod 26, the top of the limiting rod 26 extends into the receiving groove 27, one side of the limiting rod 26 is fixedly welded with one end of a fourth spring, the other end of the fourth spring is fixedly connected with the inner wall of one side of the moving groove 25, one side of the limiting rod 26 is fixedly welded with one end of a top rod 28, and the other end of the top rod 28 is in contact with one side of the long rod 21.
[0046] In the present application, the fourth rotating shaft 29 is rotatably installed on the side of the long rod 21 away from the sliding groove 23, the fourth rotating shaft 29 is fixedly welded with a pull rod 30, and the pull rod 30 is in L-shaped structure, one side of the detector shell 1 is chiseled with a clamping groove 31, and the clamping groove 31 is matched with the rotated pull rod 30, and the pull rod 30 is used for fixing the rotated long rod.
[0047] In the present application, when it is necessary to observe, first, the fixed rod 24 is slid downward, the fixed rod 24 is separated from the fixing hole 22, at the same time, the fixed rod 24 drives the moving groove 25 and the limiting rod 26 to move downward, the limiting rod 26 is separated from the receiving groove 27, then the long rod 21 is rotated, then the baffle 16 is rotated, so that the baffle 16 opens the observation hole 3, then the pull rod 30 is rotated, so that the pull rod 30 is clamped into the clamping groove 31, then the rotating rod 15 is rotated, the rotating rod 15 drives the first rotating shaft 12 to rotate and move upward, the first rotating shaft 12 drives the short rod 11 to move upward, the short rod 11 drives the cross rod 10 to move upward, the cross rod 10 drives the clamping rod 9 to move upward, the clamping rod 9 is received into the cavity 5, then the transparent observation plate 4 is clamped into the observation hole 3, then the rotating rod 15 is loosened, the second spring drives the rotating rod 15 to rotate, the rotating rod 15 drives the first rotating shaft 12 to rotate and move downward, the first rotating shaft 12 drives the short rod 11 to move downward, the short rod 11 drives the cross rod 10 to move downward, the cross rod 10 drives the clamping rod 9 to move downward, then the clamping rod 9 clamps the transparent observation plate 4, so as to achieve the purpose of observation.
[0048] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.
Claims
1. A single-chip microcomputer-based flame detector comprising a detector housing (1), characterized in that The single-chip microcomputer (2) is fixedly installed on the side bottom inner wall of the detector shell (1), an observation hole (3) is arranged on the inner wall of the side of the detector shell (1) close to the single-chip microcomputer (2), a transparent observation plate (4) is installed in the observation hole (3), cavities (5) are arranged at the top and bottom of the observation hole (3), a sliding hole (6) is arranged on the bottom inner wall of the cavity (5), a sliding rod (7) is slidably installed in the sliding hole (6), one end of the sliding rod (7) extends into the cavity (5), the other end of the sliding rod (7) extends into the observation hole (3), the side of the sliding rod (7) extending into the observation hole (3) is in contact with one side of the transparent observation plate (4), a through hole (8) is arranged on the bottom inner wall of the cavity (5), a clamping rod (9) is slidably installed in the through hole (8), one end of the clamping rod (9) extends into the cavity (5), the other end of the clamping rod (9) extends into the observation hole (3), the side of the clamping rod (9) extending into the observation hole (3) is in contact with one side of the transparent observation plate (4), one end of the clamping rod (9) extending into the cavity (5) is fixedly installed with a cross rod (10), the top of the cross rod (10) is fixedly installed with one end of a short rod (11), the other end of the short rod (11) is rotatably installed with a first rotating shaft (12); One end of a thick rod is fixedly installed on the bottom inner wall of the observation hole (3), the other end of the thick rod is rotatably installed with a rotating shaft, a baffle (16) is fixedly installed on the rotating shaft, a stop block (17) is fixedly installed on the top inner wall of the observation hole (3), one side of the stop block (17) is in contact with one side of the baffle (16), a groove (18) is arranged on the side of the detector shell (1) close to the observation hole (3), one end of a thin rod (19) is fixedly installed on the top inner wall of the groove (18), the other end of the thin rod (19) is rotatably installed with a third rotating shaft (20), one end of a long rod (21) is fixedly installed on the third rotating shaft (20), the other end of the long rod (21) is in contact with one side of the baffle (16); One side of the long rod (21) is arranged with a fixing hole (22), a sliding groove (23) is arranged on the inner wall of one side of the groove (18), a fixing rod (24) is slidably installed in the sliding groove (23), and the fixing rod (24) is in L-shaped structure, one end of a third spring is fixedly installed on the bottom of the fixing rod (24), the other end of the third spring is fixedly connected with the bottom inner wall of the sliding groove (23), and one end of the fixing rod (24) penetrates through the fixing hole (22); The top of the fixing rod (24) is arranged with a moving groove (25), a receiving groove (27) is arranged on the top inner wall of the sliding groove (23), a limiting rod (26) is slidably installed in the moving groove (25), the top of the limiting rod (26) extends into the receiving groove (27), one end of a fourth spring is fixedly installed on one side of the limiting rod (26), the other end of the fourth spring is fixedly connected with the inner wall of one side of the moving groove (25), one end of a jacking rod (28) is fixedly installed on one side of the limiting rod (26), the other end of the jacking rod (28) is in contact with one side of the long rod (21); The long rod (21) is rotatably installed with a fourth rotating shaft (29) on the side away from the sliding groove (23), the fourth rotating shaft (29) is fixedly installed with a pull rod (30), the pull rod (30) is in an L-shaped structure, a clamping groove (31) is formed on one side of the detector shell (1), and the clamping groove (31) is matched with the rotated pull rod (30).
2. A single-chip microcomputer-based flame detector according to claim 1, characterized in that, One end of the first spring is fixedly installed on one side of the sliding rod (7), and the other end of the first spring is fixedly connected with the inner wall on one side of the cavity (5).
3. The flame detector based on single-chip microcomputer according to claim 1, characterized in that, A rotating hole (13) is formed in the inner wall on one side of the cavity (5), a second rotating shaft (14) is rotatably installed in the rotating hole (13), the second rotating shaft (14) is fixedly installed with a rotating rod (15), one end of the rotating rod (15) extends into the cavity (5), the other end of the rotating rod (15) extends out of the cavity (5), and the one end of the rotating rod (15) extending into the cavity (5) is fixedly connected with the first rotating shaft (12).
4. A single-chip microcomputer-based flame detector according to claim 3, characterized in that The top of the rotating rod (15) is fixedly installed with one end of the second spring, and the other end of the second spring is fixedly connected with the inner wall on the top of the cavity (5).
5. The method of using a single chip based flame detector according to any one of claims 1 to 4, wherein, The method comprises the following steps: S1 when needing to observe, first sliding the fixed rod (24) downward, the fixed rod (24) is separated from the fixed hole (22), at the same time, the fixed rod (24) drives the moving groove (25) and the limiting rod (26) to move downward, and the limiting rod (26) is separated from the storage groove (27); S2 then rotating the long rod (21), then rotating the baffle (16), so that the baffle (16) opens the observation hole (3), then rotating the pull rod (30), so that the pull rod (30) is clamped into the clamping groove (31); S3 then rotating the rotating rod (15), the rotating rod (15) drives the first rotating shaft (12) to rotate and move upward, the first rotating shaft (12) drives the short rod (11) to move upward, the short rod (11) drives the cross rod (10) to move upward, the cross rod (10) drives the clamping rod (9) to move upward, and the clamping rod (9) is stored in the cavity (5); S4 then clamping the transparent observation plate (4) into the observation hole (3), then releasing the rotating rod (15), the second spring drives the rotating rod (15) to rotate, the rotating rod (15) drives the first rotating shaft (12) to rotate and move downward, the first rotating shaft (12) drives the short rod (11) to move downward, the short rod (11) drives the cross rod (10) to move downward, the cross rod (10) drives the clamping rod (9) to move downward, then the clamping rod (9) clamps the transparent observation plate (4), so that the observation purpose is achieved.
Citation Information
Patent Citations
High-precision flame detector and flame detection method
CN112185056A
Sealing cover for fire observation hole of boiler
CN217843929U