A laser collimator and a shafting coaxiality calculation method

Abstract

The application belongs to the field of centering measurement of rotating machinery, and particularly relates to a laser centering instrument and a shafting coaxiality calculation method. A coordinate system is established based on a reference device. Coordinates of points on each measured device are measured. The points of each measured device are at least two. An axis equation of each device is established based on the coordinates of the points of each measured device. Based on the axis equations of each measured device, coordinates of both ends of the axis of each measured device are calculated, and an axis segment of each measured device is established. The axis segment of each measured device is projected onto a projection plane perpendicular to the axis direction to obtain a plurality of projection line segments. A minimum circle containing all the projection line segments and an original point is drawn. The diameter of the minimum circle is the coaxiality of the shafting. The application can accurately convert the coordinate values of the measured device into the coaxiality. Meanwhile, the laser centering instrument can display the coaxiality of the shafting in real time based on the method of accurately converting the coordinate values of the measured device into the coaxiality.

Description

Technical Field

[0001] This application belongs to the field of centering measurement of rotating machinery, and specifically relates to a laser centering instrument and a method for calculating the coaxiality of shaft systems. Background Technology

[0002] Rotating equipment often uses drive shafts and couplings to transmit power. To ensure that the operating conditions of the couplings do not exceed their design specifications, it is necessary to understand the actual spatial position of the shaft system. Laser alignment instruments are common rotating shaft position measuring instruments. Based on laser measurement results and pre-input parameters such as equipment dimensions, they can calculate the vertical and horizontal angles and offsets of the coupling connection position, and simultaneously output the vertical and horizontal deviations of the tested equipment's anchor points. However, the "angle-offset" evaluation standard for coupling position provided by laser alignment instruments cannot intuitively characterize the macroscopic state of the shaft system, especially for units involving multiple couplings. Some high-speed precision units, in addition to focusing on the operating status of the couplings, are more concerned with the impact of shaft coaxiality on rotor dynamics, but laser alignment instruments cannot directly output the coaxiality of the shaft system. Therefore, it is necessary to convert the output data of laser alignment instruments into an overall shaft coaxiality index. Currently, there is a lack of a clear conversion method. Existing technology lacks a method for converting laser alignment instrument output data into coaxiality. Summary of the Invention

[0003] To address the aforementioned problems, this application provides a method for calculating the coaxiality of a shaft system, wherein the shaft system includes a reference device and multiple devices to be measured.

[0004] Step S1: Establish a coordinate system based on the reference device;

[0005] Step S2: Measure the coordinates of points on each device under test, with at least two points on each device under test;

[0006] Step S3: Establish the axis equations of each device based on the coordinates of the points of each device under test;

[0007] Step S4: Based on the axis equation of each tested device, calculate the coordinates of the two endpoints of the axis of each tested device, and establish the axis segment of each tested device;

[0008] Step S5: Project the axis segments of each device under test onto a projection plane perpendicular to the axis to obtain multiple projection line segments. Draw the smallest circle that includes all projection line segments and the origin. The diameter of the smallest circle is the coaxiality of the axis system, and the axis is the axis of the reference axis.

[0009] Preferably, the coordinates of points on each device under test are measured using a laser alignment instrument.

[0010] Preferably, the point is the foot of the device under test.

[0011] Preferably, the coordinate system is a three-dimensional coordinate system.

[0012] A laser alignment instrument includes a measurement module, a calculation module, and a display module;

[0013] The measurement module is used to measure the coordinates of the base of each device under test.

[0014] The calculation module is used to calculate the offset of each foot coordinate relative to the axis and to calculate the coaxiality of the axis system, including the axis of the reference axis.

[0015] Display module: used to display the offset and the coaxiality.

[0016] Preferably, the method for calculating the coaxiality of the shaft system includes:

[0017] Step S11: Establish a coordinate system based on the reference device;

[0018] Step S12: Measure the coordinates of the feet on each device under test, with at least two coordinates for each device under test;

[0019] Step S13: Establish the axis equations of each device based on the foot coordinates of each device under test;

[0020] Step S14: Based on the axis equation of each tested device, calculate the coordinates of the two endpoints of the axis of each tested device, and establish the axis segment of each tested device;

[0021] Step S15: Project the axis segments of each device under test onto a projection plane perpendicular to the axis to obtain multiple projection line segments. Draw the smallest circle that includes all projection line segments and the origin. The diameter of the smallest circle is the coaxiality of the axis system.

[0022] The advantages of this application include: this application can accurately convert the coordinate values ​​of the device under test into coaxiality. At the same time, this application also invents a laser alignment instrument, which can display the coaxiality of the axis system in real time based on the method of accurately converting the coordinate values ​​of the device under test into coaxiality. Attached Figure Description

[0023] Figure 1 This is a flowchart of a preferred embodiment of the shaft coaxiality calculation method of this application;

[0024] Figure 2 This is a connection diagram of a typical generating unit;

[0025] Figure 3 This is a schematic diagram of the axis space coordinate system according to a preferred embodiment of this application;

[0026] Figure 4 This is a schematic diagram for calculating the coaxiality of a typical generator unit. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only a part of the embodiments of this application, not all of them. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0028] A method for calculating the coaxiality of a shaft system, wherein the shaft system includes a reference device and multiple devices to be measured, such as... Figure 1 As shown, step S1: Establish a coordinate system based on the reference device; step S2: Measure the coordinates of points on each device under test, with at least two points on each device under test; step S3: Establish the axis equation of each device based on the coordinates of the points on each device under test; step S4: Calculate the coordinates of the two endpoints of the axis of each device under test based on the axis equation of each device under test, and establish the axis segment of each device under test; step S5: Project the axis segment of each device under test onto a projection plane perpendicular to the axis, obtaining multiple projection line segments, and draw the smallest circle containing all projection line segments and the origin, the diameter of which is the coaxiality of the axis system.

[0029] Furthermore, the coordinates of points on each device under test are measured using a laser alignment instrument.

[0030] Furthermore, the point refers to the foot of the device under test.

[0031] Furthermore, the coordinate system is a three-dimensional coordinate system.

[0032] In the output parameters of the laser alignment instrument, the deviation values ​​of the vertical and horizontal feet of the measured axis are calculated by the instrument's internal program based on the measurement results and the set values ​​of the relevant spacing. Theoretically, adjusting the feet of the measured equipment according to the deviation values ​​can make the axis of the measured equipment coaxial with the reference axis.

[0033] This invention is based on Figure 2 Taking a typical unit as an example, with equipment A as the reference, the left end of its rotating shaft a is connected to the shaft c of equipment C through the intermediate shaft d, while the right end of equipment A is directly connected to the shaft b of equipment B.

[0034] Establish a spatial coordinate system for the axis system, such as Figure 3The plane XY, perpendicular to the reference axis a, is set as the projection plane. The XY plane can be defined at any position within the length of the reference axis a. In this example, it is placed at the section A1 of the reference device. The intersection point 0 of the reference axis a on the projection plane (the intersection with the reference axis) is set as the origin of the projection plane. The reference axis is set as the Z-axis. The straight line passing through the intersection point 0 and parallel to the horizontal and vertical directions defined by the laser alignment instrument is set as the horizontal coordinate axis (X-axis) and the vertical coordinate axis (Y-axis).

[0035] This invention proposes using the horizontal and vertical deviations of the cross-sections where the feet of the measured rotating axis are located as the X-axis and Y-axis coordinates, and the axial position of the cross-sections where the feet are located as the Z-axis coordinate. Taking device B as an example, the spatial coordinates of its axis at cross-sections B1 and B2 can be set as (X... B1 Y B1 Z B1 ), (X B2 Y B2 Z B2 ), where X B1 X B2 Y B1 Y B2 Z represents the horizontal and vertical anchor deviation values ​​output by the laser alignment instrument. B1 Z B2 This is determined by measuring the position of the origin as defined by the section distance. Therefore, the axis vector b is...

[0036] The coordinates of the two endpoints b1 and b2 of the measured axis b can be easily determined from its axial coordinate Z. b1 Z b2 and The equation of the straight line is obtained as follows:

[0037] The spatial coordinates of point b1 are:

[0038]

[0039] The spatial coordinates of point b2 are:

[0040]

[0041] Projecting the coordinates of points b1 and b2 onto the projection plane yields points b1' and b2', then:

[0042] The plane coordinates of point b1' are:

[0043]

[0044] The plane coordinates of point b2' are:

[0045]

[0046] Connecting b1' and b2' on the projection plane forms a line segment that is the projection of axis b (if b1' and b2' coincide, the projection is a point). Then, construct a circle with the smallest diameter that includes the origin and line segment b1'-b2'; the diameter of this circle represents the coaxiality of axis b with the reference axis.

[0047] If the unit consists of multiple rotating devices, such as Figure 4 Besides axis b, there also exist axes c and d. We can project axes c and d onto the projection plane using the method described above, obtaining line segments c1'-c2' and d1'-d2'. Then, we can use a circle of minimum diameter to encompass the origin and the projected line segments representing axes b, c, and d, as shown below. Figure 3 ,but The value represents the coaxiality of the unit's shaft system.

[0048] A laser alignment instrument includes a measurement module, a calculation module, and a display module;

[0049] The measurement module is used to measure the coordinates of the base of each device under test.

[0050] The calculation module is used to calculate the offset of each foot coordinate relative to the axis and to calculate the coaxiality of the axis system. Specifically, step S11: establish a coordinate system based on the reference device; step S12: measure the foot coordinates of each device under test, with at least two foot coordinates for each device; step S13: establish the axis equation of each device based on its foot coordinates; step S14: calculate the coordinates of the two endpoints of the axis of each device under test based on its axis equation, and establish the axis segment of each device under test; step S15: project the axis segment of each device under test onto a projection plane perpendicular to the axis, obtaining multiple projection line segments, and draw a minimum circle containing all projection line segments and the origin, the diameter of which is the coaxiality of the axis system.

[0051] Display module: used to display the offset and the coaxiality.

[0052] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A shafting coaxiality calculation method, the shafting comprising a reference device and a plurality of measured devices, characterized in that: step S1: establishing a coordinate system based on the reference device; step S2: measuring the foot deviation values of each measured device in the horizontal and vertical directions; step S3: calculating the vector of the shaft of each measured device based on the foot deviation values of each measured device, and establishing the axis equation of each device according to the vector of each shaft; step S4: calculating the coordinates of the two end points of the shaft of each measured device through the positions of the two ends of the shaft in the length direction based on the axis equation of each measured device, and establishing the axis segment of each measured device; step S5: projecting the axis segment of each measured device to a projection plane perpendicular to the axial direction to obtain a plurality of projection line segments, and drawing the smallest circle containing all the projection line segments and the origin, the diameter of the smallest circle being the coaxiality of the shafting. The foot deviation values of each measured device in the horizontal and vertical directions are measured by a laser aligning instrument. The coordinate system is a three-dimensional coordinate. It comprises a measurement module, a calculation module and a display module. The measurement module is used to measure the foot coordinates of each measured device. The calculation module is used to calculate the offset of each foot coordinate relative to the axis and the coaxiality of the shafting based on the shafting coaxiality calculation method of claim 1.

2. The shafting alignment calculation method of claim 1, wherein, The display module is used to display the offset and the coaxiality.

3. The shafting alignment calculation method of claim 1, wherein, ​ 4. A laser collimator, characterized in that ​ ​ ​ ​

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