Bag filter

Abstract

To provide a bag filter capable of simplifying filter cloth exchanging operation and reducing a time for filter cloth exchange operation.SOLUTION: A bag filter 1 includes a raising / lowering part 15 which fits a filter cloth 16 to a retainer 13 while elevating it to a fitting completion position and removes the filter cloth 16 from the retainer 13 while lowering it to an exchange operation position. In a filter chamber R1, a filter cloth take-out port used as an inspection port 8 inspecting the inside of the filter chamber R1 is opened at a position further below the exchange operation position of the filter cloth 16. When exchanging filter cloths 16, a slide 20 capable of taking out the filter cloth 16 and / or the raising / lowering part 15 outside is formed in a space leading from the exchange operation position of the filter cloth 16 in the filter chamber R1 to the filter cloth take-out port 8.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an external filtration type bag filter in which a retainer suspended from a ceiling surface is covered with a bag-shaped filter cloth and used.

Background Art

[0002] There is a conventional bag filter described in Patent Document 1.

[0003] On the other hand, the applicant of the present invention has proposed, in Japanese Patent Application No. 2023-088246, a bag filter that can easily replace the filter cloth even when installed in a relatively narrow space. This bag filter has a retainer suspended from the ceiling surface of a filtration chamber into which dust-containing air is introduced, and a bag-shaped filter cloth that is detachably attached so as to cover the retainer from below and has an open upper part and a closed lower part. It is an external filtration type bag filter, and is characterized by including a lifting part that can attach the filter cloth to the retainer while raising it to the mounting completion position and detach the filter cloth from the retainer while lowering it to the replacement work position.

[0004] As a result, when the used filter cloth is lowered to the replacement work position by the elevating part, the used filter cloth is removed from the retainer at a position close to the floor surface of the filtration chamber, or is in a state of being removed from the retainer. Therefore, the operator can perform the filter cloth replacement work at a position close to the floor surface of the filtration chamber. In Patent Document 1, by means of a link mechanism composed of vertical links and horizontal links, while rotating the vertical and horizontal links, a plurality of filter cloths together with a plurality of retainers are taken out integrally (without being disassembled) to the side part of the housing. On the other hand, in Japanese Patent Application No. 2023-088246, the retainer remains in the filtration chamber, and only the movable member of the elevating part and the filter cloth can be taken out to the outside of the bag filter. Therefore, for example, even when the bag filter is installed in a relatively narrow space, the filter cloth replacement work can be appropriately carried out. Further, by raising the filter cloth before use by the movable member of the elevating part, the filter cloth is automatically attached to the retainer. In this way, the operator does not need to extract the used filter cloth from the retainer as in Patent Document 1, or attach the filter cloth before use so as to cover the retainer. Therefore, there are effects such as that the filter cloth replacement work can be easily carried out.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the inventors of the present invention have come to consider new problems such as poor workability, difficulty in reaching the filter cloth arranged inside the elevating part (near the inner central part), and time-consuming replacement work for the above-mentioned proposed bag filter.

[0007] In view of the above problems, it is a technical problem of the present invention to provide a bug filter that can simplify the filter cloth replacement work and shorten the filter cloth replacement work time more than the proposed bug filter.

Means for Solving the Problems

[0008] In order to solve the above problems, in the present invention, a retainer suspended on the ceiling surface of a filtration chamber into which dust-containing air is introduced, and a bag-shaped filter cloth that is detachably attached so as to cover the retainer from below and has an open upper part and a closed lower part, is an outside filtration type bug filter, The bug filter is provided with a lifting and lowering part that attaches the filter cloth to the retainer while raising it to the attachment completion position, and detaches the filter cloth from the retainer while lowering it to the replacement work position. In the filtration chamber, a filter cloth outlet that also serves as an inspection port for inspecting the inside of the filtration chamber is opened at a position further below the replacement work position of the filter cloth. At the time of replacing the filter cloth, a sliding table is formed in the space from the replacement work position of the filter cloth in the filtration chamber to the filter cloth outlet, so that the filter cloth and / or the lifting and lowering part can be taken out of the machine.

[0009] In the invention described in claim 2, a plurality of filter cloth outlets that also serve as the inspection ports are formed in the filtration chamber, and the sliding table is formed by combining a plurality of inspection lids for closing the inspection ports, which is the bug filter according to claim 1.

Effects of the Invention

[0010] According to the present invention, the filtration chamber is provided with a filter cloth outlet that also serves as an inspection port for inspecting the inside of the filtration chamber at a position further below than the filter cloth replacement work position. When replacing the filter cloth, a slide base is formed in the space from the filter cloth replacement work position in the filtration chamber to the filter cloth outlet, where the filter cloth and / or the lifting / lowering part can be taken out of the machine. Therefore, when replacing the filter cloth, the filter cloth can be slid out of the machine by its own weight using the slide base formed in the filtration chamber, simplifying the filter cloth replacement work and shortening the time required for the filter cloth replacement work. can be done.

[0011] Furthermore, as in claim 2, a plurality of filter cloth outlets that also serve as the inspection ports are formed in the filtration chamber, and the slide base is formed by combining a plurality of inspection lids for closing the inspection ports. Thus, there is no need to separately prepare a flat plate for forming the slide base, and the slide base can be formed by diverting and combining a plurality of inspection lids. As a result, the filter cloth can be guided from the filter cloth replacement work position to the filter cloth outlet, and the filter cloth can be safely and surely carried out of the machine and replaced with a new filter cloth.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the embodiments is merely illustrative in nature.

[0014] FIG. 1 is a schematic perspective view of a bag filter according to an embodiment of the present invention. The bag filter 1 has an outer surface filtration method and includes a main body portion 2 and a support portion 3. The main body portion 2 has a substantially quadrangular prism shape and is provided with an upper main body portion 4 and a lower main body portion 5 having a hopper shape continuously provided below the upper main body portion 4.

[0015] The support portion 3 includes four leg portions 3a. The upper end portions of each leg portion 3a are respectively connected to the four corners of the upper edge portion of the lower main body portion 5, and the lower end portions of each leg portion 3a are in contact with the ground. Also, between the two leg portions 3a on the front side of the bag filter 1 and between the two leg portions 3a on the back side thereof, connecting portions 3b1 and 3b2 intersecting the leg portions 3a are connected. A working ladder portion 3c for an operator to inspect the inside of the bag filter 1 or replace the filter cloth is attached to the connecting portion 3b1 on the front side. A similar ladder portion 3c may also be attached to the connecting portion 3b2 on the back side.

[0016] The upper main body portion 4 includes an upper plate 6 having a substantially quadrangular shape in plan view and upper side plates 7 having substantially rectangular shapes with width dimensions corresponding to the respective sides of the upper plate 6. The upper plate 6 constitutes the ceiling wall of the upper main body portion 4, and the upper side plates 7 constitute the side walls of the upper main body portion 4. Also, an inspection port 8a is opened in the lower region of the upper side plate 7a on the front side, and an openable and closable inspection lid 9a is provided at the inspection port 8a. A similar inspection port 8b is also opened in the lower region of the upper side plate 7b on the back side, and an openable and closable inspection lid 9b is provided at the inspection port 8b.

[0017] The lower main body 5 is provided with lower side plates 10 having a triangular shape on the front side, back side, right side, and left side of the bag filter 1, respectively, and each lower side plate 10 is inclined so as to be positioned on the central side of the bag filter 1 as it goes downward. A rotary valve 11 is provided at the lower end of the lower main body 5, and the dust collected inside the lower main body 5 via the rotary valve 11 can be discharged to the outside of the bag filter 1.

[0018] Next, with reference to FIGS. 2 and 3, the internal structure of the bag filter 1 will be described. In FIG. 2, for the sake of convenience of explanation, only the outer shapes of the upper plate 6 and the upper side plates 7 are shown.

[0019] As shown in FIG. 2, the internal space of the upper main body 4 is partitioned by a ceiling plate 12 into a filtration chamber R1 and a clean chamber R2. The filtration chamber R1 is a space below the ceiling plate 12, that is, a space surrounded by the lower side plates 8 of the lower main body 5, the upper side plates 7, and the ceiling plate 12. The ceiling wall is constituted by the ceiling plate 12, and the side walls are constituted by the upper side plates 7 and the lower side plates 8, respectively. On the other hand, the clean chamber R2 is a space above the ceiling plate 12, that is, a space surrounded by the upper plate 6, the upper side plates 7, and the ceiling plate 12. The ceiling wall is constituted by the upper plate 6, the side walls are constituted by the upper side plates 7, and the bottom wall is constituted by the ceiling plate 12.

[0020] As shown in FIG. 3, a plurality of first through holes 12a penetrating vertically and one communication hole 12d having a smaller diameter than the first through holes 12a are formed in the ceiling plate 12, respectively. This communication hole 12d is formed in the central portion of the ceiling plate 12. And each first through hole 12a is provided at equal intervals, for example, at a predetermined interval in the circumferential direction centered on the communication hole 12d. As shown in FIG. 2, the filtration chamber R1 and the clean chamber R2 communicate with each other through each first through hole 12a and the communication hole 12d.

[0021] On the outer peripheral side of the lower surface of the ceiling plate 12, a first umbrella portion 12c having an annular shape centered on the communication hole 12d and gradually inclined downward as it goes to the outer peripheral side is attached.

[0022] As shown in FIGS. 2 and 3, at positions corresponding to the respective first through-holes 12a on the ceiling surface 12b, that is, at the peripheries of the first through-holes 12a, retainers 13 are suspended. Each retainer 13 forms a cylindrical framework, and in a posture where its cylindrical center line extends in the vertical direction, the upper end portion is fixed to the ceiling surface 12b.

[0023] As shown in FIG. 3, below the ceiling board 12, a circular or rectangular movable member 15 whose center line faces vertically is disposed. This movable member 15 is suspended by a wire rope 14 so as to be movable up and down in its inner peripheral region. The wire rope 14 is arranged in a posture extending in the vertical direction at a substantially central portion within the upper main body 4, is inserted through the communication hole 12d of the ceiling board 12, and one end portion is fixed to the central portion of the movable member 15. Also, the lower region fixed to the movable member 15 can be twisted with respect to the upper region. Thereby, in a state where the movable member 15 is suspended by the wire rope 14, the movable member 15 can be rotated along a horizontal plane about the inner peripheral region of the movable member 15.

[0024] In the outer peripheral region of the movable member 15, second through-holes 15a penetrating in the vertical direction through which the retainers 13 can be inserted are provided, and a plurality of the second through-holes 15a are provided along the circumferential direction around the center line of the movable member 15.

[0025] At the peripheries of the respective second through-holes 15a on the lower surface of the movable member 15, annular ridge portions 15c protruding downward are provided. Also, the outer peripheral edge portion of the movable member 15 is formed in an umbrella shape that inclines so as to be gradually positioned downward toward the outer peripheral side, that is, a second umbrella portion 15b having a shape corresponding to the first umbrella portion 12c is provided. Further, a seal member is provided between the first umbrella portion 12c and the second umbrella portion 15b, and the seal member can fill the gap between the two umbrella portions when the first umbrella portion 12c and the second umbrella portion 15b are close to each other.

[0026] The filter cloth 16 is in the shape of a bag that opens upward and has an internal space larger than the outer shape of the retainer 13. The peripheral edge of the upper end opening of the filter cloth 16 is detachably attached to the outer peripheral surface of the annular ridge portion 15c of the movable member 15 by a band member. It is in a posture extending in the vertical direction when attached to the annular ridge portion 15c. Further, compressed air is supplied from an air nozzle disposed above the ceiling plate 12 into the internal space of the filter cloth 16, and the dust adhering to the outer surface of the filter cloth 16 is blown off by the compressed air and collected inside the lower main body portion 5.

[0027] As shown in FIGS. 4 and 5, a first pulley 17 and a second pulley 18 are attached to the upper surface of the upper main body portion 4. A wire rope 14 is wound around the first pulley 17 and the second pulley 18. One end of the wire rope 14 is fixed to the movable member 15, while the other end is fixed to a winding machine 19. By feeding out the wire rope 14 by the winding machine 19, the movable member 15 descends, and accordingly, the filter cloth 16 also descends. Conversely, by winding up the wire rope 14 by the winding machine 19, the movable member 15 ascends, and accordingly, the filter cloth 16 also ascends. In this way, the filter cloth 16 can be moved up and down from the outside of the bag filter 1. The other end of the wire rope 14 may be fixed to an inspection door 7a for entering the inside of the bag filter 1 in addition to the winding machine 19, and a configuration may be adopted in which the movable member 15 is moved up and down by the opening and closing operation of the inspection door 7a so that the filter cloth 16 moves up and down.

[0028] As shown in FIG. 4, when the wire rope 14 is wound up, the movable member 15 gradually ascends from below the retainer 13, and the filter cloth 16 is in a use state covering the retainer 13 (the position where the filter cloth attachment is completed shown in FIG. 4).

[0029] When the bug filter 1 is operated at this position (the fan F in Fig. 2 is operated), the dust-containing air introduced into the filtration chamber R1 is filtered by passing from the outer region to the inner region of the filter cloth 16. The cleaned air is discharged from the inner region of the filter cloth 16 to the outside of the machine through the first through-hole 12a of the ceiling plate 12 from the clean chamber R2. Since the seal member 15b is provided in the gap between the first umbrella portion 12c of the ceiling plate 12 and the second umbrella portion 15b of the movable member 15, the flow of the dust-containing air to the downstream side of the filter cloth 16 without passing through the filter cloth 16 is blocked.

[0030] As shown in Fig. 5, when the wire rope 14 is paid out, the movable member 15 gradually descends from the lower part of the retainer 13, and the filter cloth 16 is in an exchange state of being removed from the retainer 13 (the filter cloth exchange operation position shown in Fig. 5). This filter cloth exchange operation position is such that the position of the movable member 15 is lower than the filter cloth attachment completion position, and the filter cloth 16 covers a part of the retainer 12.

[0031] On the other hand, as shown in Fig. 6, inspection ports 8a, 8b for inspecting the inside of the filtration chamber R1 are opened at positions in the filtration chamber R1 that are further below the filter cloth exchange operation position. Inspection lids 9a, 9b for opening and closing the inspection ports 8a, 8b are provided at these inspection ports 8a, 8b. When these inspection ports 8a, 8b are opened, they can be used as filter cloth outlets for taking the filter cloth 16 out of the machine from the inside of the machine. Further, as shown in Fig. 6, a slide base 20 through which the filter cloth 16 and / or the movable member 15 can be taken out of the machine may be formed in the space from the filter cloth exchange operation position to the filter cloth outlets 8a, 8b. By forming such a slide base 20, when the filter cloth 16 is exchanged, the filter cloth 16 can be slid out of the machine by its own weight, simplifying the filter cloth exchange operation and shortening the time required for the filter cloth exchange operation.

[0032] The slide 20 only needs to have an inclination angle of about 60 degrees with respect to the horizontal. As the material of the slide 20, materials with a small coefficient of static friction and easy to slide, such as resin, wood, iron plate, etc., can be used. Further, the slide 20 does not have to be a single plate. For example, if a plurality of inspection lids 9a and 9b for closing the aforementioned inspection ports (filter cloth outlets) 8a and 8b are combined to form it, separately preparing a plate material for forming the slide 20 becomes unnecessary. In an example shown in FIG. 6, a rotation fulcrum 21a is provided at the upper part of the inspection lid 9a, and a rotation fulcrum 21b is provided at the lower part of the inspection lid 9b. Then, the inspection lid 9a is opened inward from the lower part of the inspection lid 9a toward the inside of the filtration chamber R1 around the rotation fulcrum 21a. On the other hand, the inspection lid 9b is opened inward from the upper part of the inspection lid 9b toward the inside of the filtration chamber R1 around the rotation fulcrum 21b. Thus, the slide 20 can be formed using two members, the inspection lid 9a and the inspection lid 9b. Just opening the inspection lid 9a and the inspection lid 9b inward cannot form the slide 20. Therefore, hereinafter, the holding method when the inspection lids 9a and 9b are opened inward will be described in detail with reference to FIGS. 7 to 9.

[0033] FIG. 7 is a schematic view when the slide 20 is formed by providing a support column for the inspection lid 9a and a support column for the inspection lid 9b. FIG. 8 is an enlarged schematic view showing a receiving fitting, and FIG. 9 is an enlarged schematic view showing a guide groove. As shown in FIG. 7, on the side wall of the upper main body portion 4, there are provided a support column 22 for supporting the inspection lid 9a when the inspection lid 9a is opened inward, and a support column 23 for suspending and supporting the inspection lid 9b when the inspection lid 9b is opened inward. As shown in FIGS. 7 and 8, the lower end of the support column 22 is rotatably supported by a support shaft 24, and a guide roller 25 is provided at the upper end. On the bottom surface side of the inspection lid 9a forming the slide 20, a receiving fitting 26 for receiving and supporting the guide roller 25 is provided. Then, when the support column 22 is rotated and the guide roller 25 of the support column 22 is fitted into the receiving fitting 26 of the inspection lid 9a, when the inspection lid 9a is opened inward, since the self-weight of the inspection lid 9a acts around the rotation fulcrum 21a, the inspection lid 9a is supported from below by the support column 22 and the inclined state is maintained.

[0034] On the one hand, as shown in FIGS. 7 and 9, the support column 23 is suspended and supported at the upper end so as to be rotatable by the support shaft 27, and a guide roller 28 is provided at the lower end. And on the bottom surface side of the inspection lid 9b forming the sliding table 20, a hinge portion 29a having a guide groove 29 formed therein for receiving the guide roller 28 and allowing it to slide is provided. If the guide roller 28 of the support column 23 is fitted into the guide groove 29, when the inspection lid 9b is opened inward, the inspection lid 9b will be suspended and supported from above by the support column 23 while rotating about the rotation fulcrum 21b, so that the inclined state is maintained.

[0035] Next, with reference to FIGS. 4 to 7, a method for replacing the filter cloth 16 will be described.

[0036] First, in order for an operator to replace the filter cloth 16, after stopping the bag filter, the inspection lids 9a and 9b are opened, and the sliding table 20 is formed at a position below the filter cloth replacement work position. The inspection lid 9a is opened inward from the lower part of the inspection lid 9a toward the inside of the filtration chamber R1 around the rotation fulcrum 21a. On the other hand, the inspection lid 9b is opened inward from the upper part of the inspection lid 9b toward the inside of the filtration chamber R1 around the rotation fulcrum 21b. For the inspection lid 9a, the guide roller 25 of the support column 22 is fitted into the receiving fitting 26 of the inspection lid 9a. As a result, since the self-weight acts on the inspection lid 9a around the rotation fulcrum 21a, it is supported from below by the support column 22 and the inclined state is maintained.

[0037] When the inspection lid 9b is opened inward, the guide roller 28 of the support column 23 slides in the guide groove 29 (in FIG. 9, the guide roller 28 shown by the two-dot chain line slides as shown by the solid line), reaches the upper end 29b side of the guide groove 29, and is suspended and supported from above by the support column 23 to maintain the inclined state.

[0038] Next, the operator operates the winch 19 to pay out the wire rope 14. Then, as shown in FIG. 5, the movable member 15 and the filter cloth 16 descend due to their own weights. As a result, the used filter cloth attached to the movable member 15 is automatically removed from the retainer 13 while descending from the attachment completion position to the filter cloth replacement work position.

[0039] Furthermore, when the operator operates the winder 19 to pay out the wire rope 14, finally, as shown in FIG. 6, the movable member 15 together with the filter cloth 16 reaches the sliding table 20 and slides down, and is taken out of the machine through the filter cloth outlet 8b on the inclined lower side of the sliding table 20.

[0040] Next, after the operator removes the filter cloth 16 from the movable member 15 taken out of the machine, the operator attaches the filter cloth 16 before use to the movable member 15.

[0041] After that, when the operator operates the winder 19 to wind up the wire rope 14, the movable member 15 fixed to the wire rope 14 rises as shown in FIG. 4. As a result, the filter cloth 16 before use attached to the movable member 15 rises from outside the machine through the replacement work position to the attachment completion position and is automatically attached to the retainer 13, and the replacement work of the filter cloth 16 is completed.

[0042] As described above, according to the present embodiment, there are provided a retainer 13 suspended from the ceiling surface 12 of the filtration chamber R1 into which the dust-containing air is introduced, and a bag-shaped filter cloth 16 that detachably covers the retainer 13 from below and is in a use state, and has an upper opening and a lower closure. The bag filter 1 is provided with a lifting part 15 that attaches the filter cloth 16 to the retainer 13 while raising it to the attachment completion position, and detaches the filter cloth 16 from the retainer 13 while lowering it to the replacement work position. In the filtration chamber R1, a filter cloth outlet that also serves as an inspection port 8 for inspecting the inside of the filtration chamber R1 is opened at a position further below the replacement work position of the filter cloth 16. When the filter cloth 16 is replaced, a sliding table 20 capable of taking out the filter cloth 16 and / or the lifting part 15 to the outside of the machine is formed in the space from the replacement work position of the filter cloth 16 in the filtration chamber R1 to the filter cloth outlet 8. Therefore, when the filter cloth 16 is replaced, the filter cloth 16 can be slid out of the machine by its own weight by the sliding table 20 formed in the filtration chamber R1, which simplifies the replacement work of the filter cloth 16 and enables the replacement work of the filter cloth 16 to be shortened.

[0043] In addition, a plurality of filter cloth outlets 8a and 8b that also serve as inspection ports are formed in the filtration chamber R1, and the sliding table 20 is formed by combining a plurality of inspection lids 9a and 9b for closing the filter cloth outlets 8a and 8b of the filter cloth 16. Therefore, it is not necessary to separately prepare a flat plate for forming the sliding table 20, and the sliding table 20 can be formed by diverting and using a combination of a plurality of inspection lids 9a and 9b. As a result, the filter cloth 16 can be guided from the filter cloth replacement work position to the filter cloth outlet 8b, and the filter cloth 16 can be safely and surely carried out of the machine and replaced with a new filter cloth.

[0044] As described above, some embodiments of the present invention have been described. However, the above-described embodiments of the invention are for facilitating the understanding of the present invention and do not limit the present invention. The present invention can be changed and improved without departing from its gist, and equivalents thereof are included in the present invention. Also, within the scope of solving at least a part of the above-described problems or achieving at least a part of the effects, combinations or omissions of the respective components described in the claims and the specification are possible.

Industrial Applicability

[0045] The present invention can be installed in processing facilities for rice and wheat such as co-drying facilities preparation facilities, rice mills, and flour mills, or various processing facilities other than rice and wheat processing facilities. In particular, it is suitable when adopting an outer surface filtration type bag filter in which a retainer suspended from the ceiling surface is covered with a bag-shaped filter cloth.

Explanation of Signs

[0046] 1 Bag filter 2 Main body part 3 Support part 4 Upper main body part 5 Lower main body part 6 Upper plate 7 Upper side plate 8 Inspection port (filter cloth outlet) 9 Inspection lid (sliding table forming member) 10 Lower side plate 11 Rotary valve 12 Ceiling board 13 Retainer 14 Wire rope 15 Movable member 16 Filter cloth 17 First pulley 18 Second pulley 19 Take-up machine 20 Sled 21 Rotation fulcrum 22 Support column 23 Support column 24 Support shaft 25 Guide roller 26 Receiving fitting 27 Support shaft 28 Guide roller 29 Guide groove 29a Hinge part

Claims

1. An outside filtration type bag filter having a retainer suspended from the ceiling surface of a filtration chamber into which dusty air is introduced, and a bag-shaped filter cloth that is detachably attached to cover the retainer from below and is in an open state at the top and a closed state at the bottom, wherein the bag filter is provided with a lifting / lowering unit that attaches the filter cloth to the retainer while raising the filter cloth to the attachment completion position and detaches the filter cloth from the retainer while lowering the filter cloth to the replacement work position, wherein a filter cloth outlet that also serves as an inspection port for inspecting the inside of the filtration chamber is opened at a position in the filtration chamber that is further below the replacement work position of the filter cloth, and a slide table capable of taking out the filter cloth and / or the lifting / lowering unit outside the machine is formed in a space from the replacement work position of the filter cloth in the filtration chamber to the filter cloth outlet when the filter cloth is replaced. The bag filter is characterized by this.

2. The bag filter according to claim 1, wherein a plurality of the filter cloth outlets that also serve as the inspection ports are formed in the filtration chamber, and the slide table is formed by combining a plurality of inspection lids for closing the inspection ports.

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