Method for butt joint alignment of cement rotary kiln shell

Abstract

The application discloses a cement rotary kiln cylinder butt joint alignment method, which comprises the following steps: 1) before butt joint, the old and new cylinders must be adjusted in roundness, and a 'rice' character support is added; 2) a second reference line M is determined; 3) a second reference line N is determined; 4) the parallelism of the fixed cylinder and the butt joint cylinder can be ensured through the two references M and N, and the coaxiality of the two cylinders can be ensured by adjusting the edge error; 5) after axial and radial adjustment, the bevels of the two side cylinders are cut, the axial nut is locked through the above method, and thus the butt joint work between the new and old cylinders and the old cylinders is completed. The cement rotary kiln cylinder butt joint alignment method has the effects of low cost, simple operation and fast construction progress.

Description

Technical Field

[0001] This invention relates to rotary kilns, and more specifically, to a method for aligning and connecting the cylinders of a cement rotary kiln. Background Technology

[0002] The cement rotary kiln is the main thermal equipment in the cement clinker production line. It is subjected to high temperature and material load for a long time. The kiln shell is the base of the rotary kiln. Replacing the shell is the main part of the equipment overhaul and renovation project. The shell connection is the key work of replacing the shell. If the shell connection does not meet the specifications, it will cause the shell to swing during operation, which will aggravate the wear of refractory materials and, in severe cases, cause the shell to crack at the joint. Summary of the Invention

[0003] The purpose of this invention is to provide a method for aligning and connecting the cylinders of a cement rotary kiln. This method has the advantages of low cost, simple operation, and fast construction progress.

[0004] To achieve the above objectives, the present invention provides a method for aligning and connecting the cylinders of a cement rotary kiln, the method comprising:

[0005] 1) Before docking, the old and new cylinders must be rounded and supported with a "rice" shape.

[0006] 2) Determine the second baseline M: Select the position of the collar or gear ring cylinder in the fixed cylinder, and the generatrix of the selected position represents the ideal generatrix of the fixed cylinder, reflecting the center line of the cylinder. Find more than 4 representative positions, then use a square to make a chord, use a frame level to level, and drop a plumb bob at the midpoint of the chord. The point where the tip of the plumb bob intersects with the cylinder wall is point A; repeat the above method to find other points. The line connecting these points is a generatrix of the cylinder. Draw a parallel line above the generatrix as the baseline M for aligning the newly installed cylinder.

[0007] 3) Determine the second reference line N: After finding the first generatrix, draw arcs on one side of the inner wall of the cylinder with A, B, C, and D as centers and chord length 1.414R as radius. Then draw the common tangent line of these four arcs and their respective tangent points A1, B1, C1, and D1. This tangent line is the other generatrix of the cylinder. Determine every two reference lines N of the newly installed cylinder using the above method.

[0008] 4) The parallelism between the fixed cylinder and the docking cylinder can be guaranteed by the two references M and N, and the coaxiality of the two cylinders can be guaranteed by adjusting the misalignment.

[0009] 5) After axial and radial adjustments, cut the bevels on both sides of the cylinder and tighten the axial nuts as described above. This completes the docking work between the new and old cylinders and between the old cylinders.

[0010] Preferably, in step 2), a parallel line is drawn using a Ф0.5mm steel wire at a position 100mm directly above the busbar as the reference line M for aligning the newly installed cylinder.

[0011] Preferably, in step 4), the misalignment of the coaxiality is less than or equal to 2 mm.

[0012] Preferably, in step 5), a 3-5mm gap is left between the two cylinders.

[0013] In the above technical solution, taking a 5000t / d rotary kiln as an example, this method of cylinder docking can not only ensure the construction quality and avoid kiln shutdown failures due to poor cylinder docking quality after kiln start-up, but also save construction time. Generally, cylinder docking is the main construction project during maintenance, which determines the length of maintenance time. Using this construction method can greatly shorten the construction period and reduce costs.

[0014] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0015] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0016] Figure 1 A schematic diagram of the rice-shaped support;

[0017] Figure 2 To determine the busbar schematic diagram;

[0018] Figure 3 Find the reference points M and N for the busbar method. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] In this invention, unless otherwise stated, directional words such as "upper" and "lower" included in the terminology only represent the orientation of the term in its normal use or are common terms understood by those skilled in the art, and should not be regarded as a limitation on the term.

[0021] This invention provides a method for aligning the cylinders of a cement rotary kiln (taking a 5000t / d kiln as an example). Connecting new and old cylinders, or connecting old cylinders, is more difficult than connecting new cylinders because the end face of the old cylinder is an unmachined surface, and this cross-section is not necessarily circular. Furthermore, there are localized uneven deformations inside the cylinder that are difficult to correct. Therefore, for connecting old cylinders, we use the busbar method for alignment, effectively ensuring construction quality and facilitating precise alignment of the cylinders. When using the busbar alignment method, first, an ideal busbar is found, and two reference lines M and N are determined for the cylinders to be connected. The centerlines of the two cylinders are made parallel, and the misalignment is adjusted to make the centers of the two cylinders coincide. The specific operation steps are as follows:

[0022] a) Before docking, the old and new cylinders must be rounded and reinforced with a cross-shaped support (see...). Figure 1 Ideally, an inner support ring should be added to ensure the quality of the connection and reduce the internal stress during welding.

[0023] b) Select a position within the fixed cylinder where the deformation of the collar or gear ring is minimal. The generatrix of the selected position should represent the ideal generatrix of the fixed cylinder, reflecting its centerline. Find at least four representative positions. Then, use a square to create a chord, and a frame level to ensure levelness. Place a plumb bob at the midpoint of the chord; the point where the tip of the plumb bob intersects the cylinder wall is designated as point A (see...). Figure 2 Repeat the above method to find the other points. The line connecting these points forms a generatrix of the cylinder. At a position 100mm directly above this generatrix, use a 0.5mm diameter steel wire to draw a parallel line as the reference line M for aligning the newly installed cylinder. (See...) Figure 2 .

[0024] c) Since the rotary kiln can no longer rotate, the second reference line N cannot be determined using the above method. Only after finding the first generatrix can arcs be drawn on one side of the inner wall of the cylinder, centered at A, B, C, and D, with a radius of chord length 1.414R. Then, draw the common tangent line of these four arcs and their respective tangent points A1, B1, C1, and D1. This tangent line is the other generatrix of the cylinder. The second reference line N for the newly installed cylinder is determined using the above method (see...). Figure 3 ).

[0025] d) The parallelism between the fixed cylinder and the docking cylinder can be guaranteed by the two references M and N. The coaxiality of the two cylinders can be guaranteed by adjusting the misalignment. The misalignment is less than or equal to 2mm.

[0026] e) After axial and radial adjustments, leave a 3mm gap for the connection, cut the bevels on both sides of the cylinder, and tighten the axial nuts as described above. This completes the connection between the new and old cylinders and between the old cylinders.

[0027] The preferred 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 specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0028] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0029] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for butt alignment of a cement rotary kiln shell, characterized in that, The method includes: 1) Before docking, the old and new cylinders must be rounded and "rice" shaped supports must be added; 2) Determine the second baseline M: Select the position of the collar or gear ring cylinder in the fixed cylinder, and the generatrix of the selected position represents the ideal generatrix of the fixed cylinder, reflecting the center line of the cylinder. Find more than 4 representative positions, then use a square to make a chord, use a frame level to level, and drop a plumb bob at the midpoint of the chord. The point where the tip of the plumb bob intersects with the cylinder wall is point A; repeat the above method to find other points. The line connecting these points is a generatrix of the cylinder. Draw a parallel line above the generatrix as the baseline M for aligning the newly installed cylinder. 3) Determine the second reference line N: After finding the first generatrix, draw arcs on one side of the inner wall of the cylinder with A, B, C, and D as centers and chord length 1.414R as radius. Then draw the common tangent line of these four arcs and their respective tangent points A1, B1, C1, and D1. This tangent line is the other generatrix of the cylinder. Determine every two reference lines N of the newly installed cylinder using the above method. 4) The parallelism between the fixed cylinder and the docking cylinder can be guaranteed by the two references M and N, and the coaxiality of the two cylinders can be guaranteed by adjusting the misalignment. 5) After axial and radial adjustments, cut the bevels on both sides of the cylinder and tighten the axial nuts as described above. This completes the docking work between the new and old cylinders and between the old cylinders.

2. The method of aligning the cement rotary kiln shell butt joint according to claim 1, characterized in that, In step 2), a parallel line is drawn using a Ф0.5mm steel wire at a position 100mm directly above the busbar as the reference line M for aligning the newly installed cylinder.

3. The method of aligning the cement rotary kiln shell butt joint of claim 1, wherein, In step 4), the misalignment of the coaxiality is less than or equal to 2 mm.

4. The method of aligning the cement rotary kiln shell butt joint of claim 1, wherein, In step 5), a 3-5mm gap is left between the two cylinders.

Images