An efficient energy-saving pneumatic slag poking device for a boiler slag dropping pipe

Abstract

The present invention belongs to the technical field of boiler structures, and particularly relates to an energy-efficient pneumatic slag poking device for a boiler slag discharge pipe. The structure includes a slag discharge pipe, and further includes a stop valve arranged at the lower end pipe orifice position of the slag discharge pipe, an expansion joint arranged on the slag discharge pipe, and a horizontal air inlet pipe arranged on the slag discharge pipe. The beneficial effects at least include: during the pneumatic slag poking operation, the stop valve can be closed, so that unburned red slag and large coke lumps can return to the furnace. In this way, the blocked section in the slag discharge pipe can be dredged, the heat contained in the red slag can be avoided from being wasted, and dust generation can also be avoided. After the pneumatic slag poking operation, the stop valve is opened again, which does not affect the normal slag discharge function.

Description

Technical Field

[0001] The invention belongs to the technical field of boiler structures, and in particular relates to a high-efficiency and energy-saving pneumatic slag-poking device for a boiler slag-dropping pipe. Background Art

[0002] Boiler refers to a kind of energy conversion equipment. Generally, combustion operation is carried out in the boiler to output steam with a certain amount of thermal energy, which can directly provide thermal energy or indirectly provide electrical energy.

[0003] The structure of the boiler mainly includes the furnace body, smoke exhaust pipe, slag pipe, and steam drum. Since the boiler started to burn sludge, the slag pipe has been blocked more frequently. There are two main methods for removing slag from the slag pipe: manual slag removal and air cannon slag removal. The former is relatively dangerous, while the latter is relatively safe and advanced.

[0004] For example, the Chinese utility model patent with authorization announcement number CN209857037U and authorization announcement date 2019.12.27 discloses a circulating fluidized bed boiler slag prying device, whose structure includes: a slag discharge pipe, an anti-fall wire rope, a slag prying pipe, a gate valve, a gun barrel, an air gun body, a solenoid valve, an air intake hose, an air gun support, a support frame, and a muzzle flap.

[0005] The slag-poking device in this utility model patent has the following advantages: easy operation, reduced labor intensity, reduced operational risks, and improved boiler operation stability.

[0006] However, in actual use, the slag-poking device has problems such as unsafe and inefficient slag-poking operation, and has many safety hazards. For example, the air cannon body can not only poke the slag upward into the furnace, but also poke part of the slag downward out of the slag discharge pipe. The downward slag generally carries a small amount of unburned red slag, has a high temperature, and produces a large amount of dust, which pollutes the surrounding environment and causes great health hazards to the operators. Summary of the invention

[0007] The invention provides a high-efficiency and energy-saving pneumatic slag-pushing device for a boiler slag-dropping pipe, and aims to solve the technical problem of how to make the slag-pushing operation more efficient and energy-saving, avoid the waste of unburned red slag, and avoid the formation of large dust hazards on site.

[0008] The technical solution adopted by the present invention to solve the above-mentioned problem is: a high-efficiency and energy-saving pneumatic slag-poking device for a boiler slag-dropping pipe, the structure of which includes a slag-dropping pipe, a stop valve arranged at the lower end of the slag-dropping pipe, an expansion joint arranged on the slag-dropping pipe, and a transverse air inlet pipe arranged on the slag-dropping pipe.

[0009] A further preferred technical solution is that: it further includes an arc-shaped inner lining plate arranged on the inner ring surface of the slag dropping pipe and used to block the slag poking air flow.

[0010] A further preferred technical solution is that: it further includes an air tank outlet pipe arranged on the horizontal air inlet pipe, a compressed air tank arranged on the air tank outlet pipe, and a check valve arranged on the air tank outlet pipe.

[0011] A further preferred technical solution is that: it further includes an air tank inlet pipe arranged on the compressed air tank, and a main compressed air pipe arranged on the air tank inlet pipe.

[0012] A further preferred technical solution is that: it further includes a vertical rectangular opening arranged on the slag dropping pipe, and a lifting drive plate arranged on the outer ring surface of the arc-shaped inner lining plate, inserted into the vertical rectangular opening, and used to assist in slag poking by vertically moving the arc-shaped inner lining plate.

[0013] A further preferred technical solution is that: it further includes a horizontal screw rod arranged on the outer ring surface of the arc-shaped inner lining plate and inserted into the vertical rectangular opening, and a fastening nut arranged on the horizontal screw rod and used to clamp the outer ring surface of the slag dropping pipe.

[0014] A further preferred technical solution is that: it further includes a connection hole arranged on the slag dropping pipe and used to insert the horizontal air inlet pipe.

[0015] A further preferred technical solution is that: it further includes two positioning arc-shaped grooves respectively arranged on two vertical sides of the arc-shaped inner lining plate and used to engage with the horizontal air inlet pipe.

[0016] A further preferred technical solution is that: it further includes a jack and a plug rod respectively arranged at two side positions of the arc-shaped inner lining plate and used to disassemble the arc-shaped inner lining plate by inserting into each other and then bending and overlapping the arc-shaped inner lining plate.

[0017] A further preferred technical solution is that: it further includes a cylinder connection hole arranged on the lifting drive plate.

[0018] The beneficial effects of the present invention at least include:

[0019] First, during the pneumatic slag poking operation, the stop valve can be closed, so that the unburned red slag and large coke lumps can return to the furnace. In this way, it can not only dredge the blocked section in the slag dropping pipe, but also avoid the waste of heat contained in the red slag, and can also avoid the generation of dust. After the pneumatic slag poking operation, the stop valve is opened again, which does not affect the normal slag discharging function;

[0020] Second, the structure and operation of the pneumatic slag poking have comprehensive safety. The slag dropping pipe is fixedly installed firmly and is not easily damaged by heat;

[0021] Third, the air cannon slag poking effect provided by the main compressed air pipe and the compressed air tank is safe and convenient enough for large-scale use;

[0022] Fourth, the arc-shaped inner lining plate can not only protect the slag dropping pipe in a strong air flow but also has a mechanical active slag poking function;

[0023] Fifth, the arc-shaped inner lining plate has the dual advantages of being stable during use and convenient for disassembly and assembly. Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of the present invention.

[0025] Figure 2 It is a schematic diagram of the position and shape of the arc-shaped inner lining plate in the present invention from a top view angle.

[0026] Figure 3 It is a schematic diagram of the position of the compressed air tank in the present invention.

[0027] Figure 4 It is a schematic diagram of the position and shape of the lifting drive plate and the transverse screw in the present invention.

[0028] Figure 5 It is a schematic diagram of the mechanical active slag poking operation of the arc-shaped inner lining plate in the present invention.

[0029] Figure 6 It is another schematic diagram of the shape structure of the arc-shaped inner lining plate in the present invention.

[0030] Figure 7 It is a schematic diagram of the usage mode of the jack and the plug rod when the arc-shaped inner lining plate is disassembled and assembled in the present invention.

[0031] In the figure, the meanings of the various marks are as follows:

[0032] Furnace body a, blocked section slag b, unfolded use position c of the arc-shaped inner lining plate, first moving direction d when the arc-shaped inner lining plate is disassembled;

[0033] Slag dropping pipe 21;

[0034] Cut-off valve 1, expansion joint 2, transverse air inlet pipe 3, arc-shaped inner lining plate 4, air tank outlet pipe 18, compressed air tank 5, check valve 6, air tank inlet pipe 7, main compressed air pipe 8, vertical rectangular opening 9, lifting drive plate 10, transverse screw 11, fastening nut 12, connection hole 13, positioning arc-shaped groove 14, jack 15, plug rod 16, cylinder connection hole 17. Detailed Embodiments

[0035] The following is only a preferred embodiment of the present invention and does not limit the scope of the present invention.

[0036] As shown in the attached Figures 1-7 As shown, a high-efficiency and energy-saving pneumatic slag poking device for a boiler slag discharge pipe, the structure includes a slag discharge pipe 21, and also includes a stop valve 1 arranged at the lower end pipe orifice position of the slag discharge pipe 21, an expansion joint 2 arranged on the slag discharge pipe 21, and a horizontal air inlet pipe 3 arranged on the slag discharge pipe 21.

[0037] In this embodiment, the slag discharge pipe 21 is vertically arranged, the upper end is butted with the slag discharge port on the furnace body a and is welded and fixed, and it is divided into two parts by itself, and the expansion joint 2 is installed between the two pipe bodies. So far, the furnace body a is fixedly installed, and the lower pipe body of the slag discharge pipe 21 together with the stop valve 1 and the horizontal air inlet pipe 3 are also fixedly installed. After cooperating with the expansion joint 2, the pneumatic slag poking device has at least the following two advantages:

[0038] First, each part is fixedly installed, the installation is stable, and it can be used stably;

[0039] Second, the thermal expansion and contraction phenomenon of the furnace body a will not affect the installation stability of the lower pipe body of the slag discharge pipe 21, the stop valve 1, and the horizontal air inlet pipe 3.

[0040] Among them, the materials of the slag discharge pipe 21 and the horizontal air inlet pipe 3 are carbon steel pipes with outstanding heat resistance. The main function of the latter is to prevent the unburned red slag from touching and burning out the externally connected compressed air pipeline, because the commonly used pipeline material for the compressed air pipeline is a metal braided pipe, and its heat resistance is relatively low, not as good as the above-mentioned carbon steel pipe.

[0041] In addition, the expansion joint 2 is a commercially available product, which has sufficient and appropriate telescopic performance in the vertical length direction, but its radial dimension is not easy to change, at least the impact force of the compressed air will not make it expand radially. Its material is also steel with outstanding heat resistance. A small amount of slag may accumulate in the fold gaps of it, but it does not affect the overall slag discharge effect and slag poking function.

[0042] Finally, the usage method of the stop valve 1 is generally as follows:

[0043] First, during the pneumatic slag poking operation, the stop valve 1 is generally in the closed state. After the compressed air enters the slag discharge pipe 21, it finally all enters the furnace body a. At this time, the blocked slag is blown and loosened. If there is unburned red slag in it, it will return to the furnace body a again, making full use of its heat, while solving the problem of slag blockage and the problem of waste of red slag heat. Therefore, correspondingly, the position of the horizontal air inlet pipe 3 on the slag discharge pipe 21 needs to be appropriately lower;

[0044] Second, after the pneumatic slag poking operation, the cut-off valve 1 is normally open or opened and closed regularly for normal slag discharging operation. At this time, the problems of a small amount of discharged unburned red slag and slight dust under the slag dropping pipe 21 are normal phenomena and will not cause significant harm to the surrounding environment and operators.

[0045] Third, during the pneumatic slag poking operation, the cut-off valve 1 can also be in an open state. At this time, to ensure sufficient safety, the intensity of the compressed air can be adjusted to an appropriately low level. Therefore, this method is applicable to the situation where the degree of slag blockage in the furnace is relatively light.

[0046] The pneumatic slag poking device further includes an arc-shaped inner lining plate 4 arranged on the inner ring surface of the slag dropping pipe 21 and used to block the poking slag air flow.

[0047] In this embodiment, the material of the arc-shaped inner lining plate 4 is the same as that of the slag dropping pipe 21. The central angle of the cross-sectional shape of the former can be greater than or less than 180°. Its main function is:

[0048] In the area on the inner ring surface of the slag dropping pipe 21 that is horizontally opposite to the horizontal air inlet pipe 3, a thickened structure is formed, so that the slag dropping pipe 21 at this place is not easily broken by the high-intensity air flow and a hole is avoided being formed by the impact.

[0049] On the other hand, the installation method of the arc-shaped inner lining plate 4 is by attachment. Compared with the method of directly reserving a thickened section at the above position, the advantage is that through the disassembly and replacement method, the above-mentioned effect of blocking the air flow can always be effective. Otherwise, after the above-mentioned thickened section is worn out by the impact, it is still necessary to replace the slag dropping pipe 21 together, which is very time-consuming, laborious and wasteful of materials.

[0050] Among them, the arc-shaped inner lining plate 4 has appropriate elasticity and has a tendency to expand and spread on the inner ring surface of the slag dropping pipe 21. Therefore, it can press the inner ring surface of the slag dropping pipe 21 so that it is not easy to fall off. Its spread shape is rectangular, and its length and width dimensions are relatively large, at least ensuring that: the horizontal projection of the horizontal air inlet pipe 3 is all located on it, and its thickness dimension is 2 - 5 mm, or the thickness dimension of the slag dropping pipe 21 is followed.

[0051] The pneumatic slag poking device further includes an air tank outlet pipe 18 arranged on the horizontal air inlet pipe 3, a compressed air tank 5 arranged on the air tank outlet pipe 18, and a check valve 6 arranged on the air tank outlet pipe 18.

[0052] In this embodiment, the material of the air tank outlet pipe 18 is the above-mentioned metal braided pipe. The compressed air tank 5 is a commercially available product, and its internal pressure ≥ 0.3 MPa. Whether it has its own pressurization function or not is acceptable, as long as a high-pressure air flow can be ejected at the horizontal air inlet pipe 3 finally.

[0053] Among them, the check valve 6 is also a commercially available product, and its function is also existing, which can prevent the air flow from returning to the compressed air tank 5. Correspondingly, the check valve 6 can also be the switch of the pneumatic slag poking device. After it is opened, the high-pressure air flow can disperse the blocked slag, achieving the effect of pneumatic slag poking.

[0054] The pneumatic slag poking device further includes an air tank inlet pipe 7 provided on the compressed air tank 5, and a main compressed air pipe 8 provided on the air tank inlet pipe 7.

[0055] In this embodiment, the main compressed air pipe 8 is connected to a larger compressed air container or a compressed air pump, ensuring that all boilers in the workshop can perform pneumatic slag poking operations as needed, which is very efficient and convenient.

[0056] Among them, common existing valves can also be provided on the air tank inlet pipe 7 and / or the main compressed air pipe 8 as needed, making the flow of compressed air safer and more efficient.

[0057] The pneumatic slag poking device further includes a vertical rectangular opening 9 provided on the slag dropping pipe 21, and a lifting drive plate 10 provided on the outer circumferential surface of the arc-shaped inner lining plate 4, inserted into the vertical rectangular opening 9, and used for assisting in slag poking by vertically moving the arc-shaped inner lining plate 4.

[0058] In this embodiment, after the arc-shaped inner lining plate 4 is combined with the vertical rectangular opening 9 and the lifting drive plate 10, it has an important second function, that is, mechanical active slag poking operation.

[0059] At this time, part of the blocked slag b is stuck on the arc-shaped inner lining plate 4 or slightly higher than the arc-shaped inner lining plate 4. The lifting drive plate 10 drives the arc-shaped inner lining plate 4 to perform multiple lifting operations, which can assist in pneumatic slag poking and achieve a more efficient slag poking effect.

[0060] It should be noted that:

[0061] First, when the lifting drive plate 10 is at the highest and lowest positions on the vertical rectangular opening 9, the arc-shaped inner lining plate 4 always completely covers the vertical rectangular opening 9, and its own shape remains unchanged and always adheres to the inner circumferential surface of the slag dropping pipe 21, without obvious air leakage.

[0062] Second, even if there is a slight air leakage at the vertical rectangular opening 9, it does reduce the intensity of pneumatic slag poking. However, compared with the gain effect brought by the mechanical slag poking operation during the lifting process of the arc-shaped inner lining plate 4, it can be completely ignored. The advantages of opening the vertical rectangular opening 9 far outweigh the associated disadvantages.

[0063] The pneumatic slag poking device further includes a transverse screw 11 disposed on the outer circumferential surface of the arc-shaped inner lining plate 4 and inserted into the vertical rectangular opening 9, and a fastening nut 12 disposed on the transverse screw 11 and used for clamping the outer circumferential surface of the slag dropping pipe 21.

[0064] In this embodiment, when the arc-shaped inner lining plate 4 does not need to lift itself and mechanically poke the slag, the fastening nut 12 tightly presses the outer circumferential surface of the slag dropping pipe 21 to ensure sufficient sealing performance between the arc-shaped inner lining plate 4 and the inner circumferential surface of the slag dropping pipe 21.

[0065] When the arc-shaped inner lining plate 4 is lifted to poke the slag, the fastening nut 12 is only slightly loosened so that the arc-shaped inner lining plate 4 can be lifted. There is still no obvious gap left between the arc-shaped inner lining plate 4 and the slag dropping pipe 21. Otherwise, not only air leakage will occur at this gap, but also slag dust will float out of the furnace, which is both inefficient and unsafe.

[0066] In addition, during the entire installation, use, lifting, and use process of the arc-shaped inner lining plate 4, the lifting drive plates 10 and one or two transverse screws 11 always fit against the vertical sides of the vertical rectangular opening 9 to prevent the arc-shaped inner lining plate 4 from tilting.

[0067] The pneumatic slag poking device further includes a connection hole 13 disposed on the slag dropping pipe 21 and used for inserting the transverse air inlet pipe 3.

[0068] In this embodiment, the transverse air inlet pipe 3 is first inserted into the connection hole 13, and then the former and the slag dropping pipe 21 are welded in a complete circle to ensure relatively high installation stability of the transverse air inlet pipe 3.

[0069] The pneumatic slag poking device further includes two positioning arc-shaped grooves 14 respectively disposed on two vertical sides of the arc-shaped inner lining plate 4 and used for clamping the transverse air inlet pipe 3.

[0070] In this embodiment, the positioning arc-shaped groove 14 is used in cooperation with the arc-shaped inner lining plate 4 with a cross-sectional central angle degree > 180°.

[0071] The diameter of the circle corresponding to the arc-shaped edge of the positioning arc-shaped groove 14 is slightly larger than the outer diameter of the transverse air inlet pipe 3, so that the two can be matched and clamped, thereby providing a unique and fixed clamping position for the arc-shaped inner lining plate 4 to ensure that the arc-shaped inner lining plate 4 is not easily deflected and has a unique fixed position.

[0072] During the lifting of the arc-shaped inner lining plate 4 and the subsequent active slag poking process, it needs to deform appropriately, so that the horizontal air inlet pipe 3 first slides out of the positioning arc-shaped groove 14 relatively, and then snaps into the positioning arc-shaped groove 14 relatively. This is one of the reasons why the arc-shaped inner lining plate 4 needs to have appropriate elasticity itself.

[0073] Correspondingly, the setting of the positioning arc-shaped groove 14 also makes the lifting drive of the lifting drive plate 10 simpler and more convenient. There is no need to set a lifting amplitude memory function. When the horizontal air inlet pipe 3 snaps into the positioning arc-shaped groove 14, for example, making a "click" sound indicates the correct end point of the arc-shaped inner lining plate 4 descending and resetting after active slag poking.

[0074] The pneumatic slag poking device further includes a jack 15 and a plug 16 which are respectively arranged at two side positions of the arc-shaped inner lining plate 4 and are used to disassemble the arc-shaped inner lining plate 4 by bending and overlapping the arc-shaped inner lining plate 4 with each other through mutual insertion.

[0075] In this embodiment, the jack 15 and the plug 16 are only effective when the arc-shaped inner lining plate 4 is disassembled and assembled.

[0076] As shown in the appendix Figure 6 At this time, the horizontal bending amplitude of the arc-shaped inner lining plate 4 is much larger than its normal use state, and it is not necessarily a circular contour. The equivalent diameter at this time is much smaller than the slag dropping pipe 21. Therefore, the arc-shaped inner lining plate 4 can be disassembled and replaced in the slag dropping pipe 21 together with the lifting drive plate 10.

[0077] The insertion of the jack 15 and the plug 16 ensures that the above-mentioned greatly bent and partially overlapped closed state will not be accidentally opened, at least not accidentally opened during the disassembly and assembly of the arc-shaped inner lining plate 4. Otherwise, the arc-shaped inner lining plate 4 will adhere to the slag dropping pipe 21 again and it will be difficult to disassemble and assemble.

[0078] Correspondingly, the disassembly method of the arc-shaped inner lining plate 4 is as follows: first, it bends greatly and partially overlaps itself, then the plug 16 is inserted into the jack 15, and then along the first moving direction d when the arc-shaped inner lining plate is disassembled, the lifting drive plate 10 is moved away from the vertical rectangular opening 9, and finally it is taken out downward. Conversely, it is the installation method, and the operation method is the same.

[0079] Among them, the number of the jack 15 and the plug 16 is 2 each. The two jacks 15 are arranged at the upper and lower positions of one of the positioning arc-shaped grooves 14, and the two plugs 16 are arranged at the upper and lower positions of the other positioning arc-shaped groove 14. For details, please refer to the appendix Figure 6 . The insertion size relationship between the jack 15 and the plug 16 does not need to be exactly tight.

[0080] The pneumatic slag poking device further includes a cylinder connection hole 17 provided on the lifting drive plate 10.

[0081] In this embodiment, the meaning of the above-mentioned "high efficiency and energy saving" at least includes:

[0082] Compared with manual slag poking operation, the pneumatic slag poking operation already has prominent high-efficiency characteristics;

[0083] Compared with the existing common pneumatic slag poking methods, the above-mentioned pneumatic slag poking operation has the advantages of higher stability, efficiency, and improved safety;

[0084] When the pneumatic slag poking operation is carried out, the cut-off valve 1 can be closed, so that the unburned red slag can return to the furnace body a for re-combustion and use, which is very efficient and energy-saving;

[0085] The self-lifting slag poking effect of the auxiliary arc-shaped lining plate 4 can further improve the slag poking efficiency.

[0086] Finally, the cylinder installed on the cylinder connection hole 17 and the lower pipe body of the slag dropping pipe 21 are installed on the same fixing frame to ensure the effective and convenient lifting action of the arc-shaped lining plate 4.

[0087] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art in the said technical field, various modifications can be made without departing from the gist of the present invention. These are all non-creative modifications and are protected by the patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A high-efficiency and energy-saving pneumatic slag-poking device for a boiler slag-poking pipe, the structure comprising a slag-poking pipe (21), characterized in that: It also comprises a stop valve (1) arranged at the lower end of the slag dropping pipe (21), an expansion joint (2) arranged on the slag dropping pipe (21), and a transverse air inlet pipe (3) arranged on the slag dropping pipe (21). It also includes an arc-shaped inner lining plate (4) arranged on the inner annular surface of the slag dropping pipe (21) and used to block the slag-poking airflow. It also includes a vertical rectangular opening (9) provided on the slag dropping pipe (21), and a lifting drive plate (10) provided on the outer annular surface of the arc-shaped inner lining plate (4), plugged into the vertical rectangular opening (9), and used to assist in slag removal by vertically moving the arc-shaped inner lining plate (4).

2. The high-efficiency and energy-saving pneumatic slag-poking device for a boiler slag-dropping pipe according to claim 1 is characterized in that: It also includes an air tank outlet pipe (18) arranged on the transverse air inlet pipe (3), a compressed air tank (5) arranged on the air tank outlet pipe (18), and a check valve (6) arranged on the air tank outlet pipe (18).

3. The high-efficiency and energy-saving pneumatic slag-poking device for a boiler slag-dropping pipe according to claim 2 is characterized in that: It also includes an air tank air intake pipe (7) arranged on the compressed air tank (5), and a compressed air main pipe (8) arranged on the air tank air intake pipe (7).

4. The high-efficiency and energy-saving pneumatic slag-moving device for a boiler slag-moving pipe according to claim 1 is characterized in that: It also includes a transverse screw (11) disposed on the outer annular surface of the arc-shaped inner lining plate (4) and inserted into the vertical rectangular opening (9), and a fastening nut (12) disposed on the transverse screw (11) and used to clamp the outer annular surface of the slag dropping pipe (21).

5. The high-efficiency and energy-saving pneumatic slag-moving device for a boiler slag-moving pipe according to claim 1 is characterized in that: It also includes a connection hole (13) arranged on the slag dropping pipe (21) and used for plugging into the transverse air intake pipe (3).

6. The high-efficiency and energy-saving pneumatic slag-moving device for a boiler slag-moving pipe according to claim 5, characterized in that: It also includes two positioning arc grooves (14) which are respectively arranged on two vertical sides of the arc-shaped inner lining plate (4) and are used to engage with the transverse air intake pipe (3).

7. The high-efficiency and energy-saving pneumatic slag-moving device for a boiler slag-moving pipe according to claim 1 is characterized in that: It also includes insertion holes (15) and insertion rods (16) which are respectively arranged at two side positions on the arc-shaped inner lining plate (4) and are used for disassembling the arc-shaped inner lining plate (4) by means of mutual insertion and bending to overlap the arc-shaped inner lining plate (4).

8. The high-efficiency and energy-saving pneumatic slag-pushing device for a boiler slag-dropping pipe according to claim 1 is characterized in that: It also includes a cylinder connection hole (17) arranged on the lifting drive plate (10).

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