Measuring apparatus and measuring method

Abstract

To provide a measuring instrument capable of shortening the measuring period of the abrasion loss of an object to be measured and reducing human labor required for measuring work.SOLUTION: A measurement apparatus comprising: a pressing unit configured to press a measurement target in a direction opposite to a direction in which the measurement target protrudes and adjust a position of the measurement target; a measurement unit configured to measure a surface shape of the measurement target whose position is adjusted by the pressing unit; a calculation unit configured to calculate a differential thickness by comparing the surface shape measured by the measurement unit with a preset reference shape; and a housing configured to hold at least the pressing unit and the measurement unit.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a measuring device and a measuring method for measuring the surface shape of a measurement object and calculating the amount of wear of the measurement object. [Background technology]

[0002] A rolling mill is used to roll a material to be rolled, such as a steel plate. The rolling mill has a pair of upper and lower work rolls that roll the material to be rolled, and a pair of upper and lower auxiliary rolls that support the work rolls.

[0003] The rolls of a rolling mill are installed in left and right housings located on the operating side (op side) and drive side (dr side) via roll chocks attached to both ends of their axial direction. In this case, clearance is provided between the roll chocks and the housings to facilitate the replacement of the rolls.

[0004] If rolling is performed simply with a clearance provided, the position of the roll chocks will fluctuate due to the force applied to the rolls, which will cause a large change in the roll cross between the work rolls and the auxiliary rolls, deteriorating the threadability of the rolled material and potentially causing the tail end of the rolled material to meander, resulting in strip squeezing.

[0005] Therefore, as in Patent Document 1, a technology is known in which a chock liner is placed between the roll chock and the housing to fill the clearance between the roll chock and the housing in one direction, thereby maintaining the passability of the rolled material. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5904003 Summary of the Invention [Problem to be solved by the invention]

[0007] In a pair-cross rolling mill, in which an upper work roll and a lower work roll cross each other, a crosshead is provided between the roll chocks and the housing, and a liner is provided at the end of the crosshead that contacts the roll chock. The liner absorbs the load received from the roll chock and suppresses transmission of the load to the crosshead and the housing. In a pair-cross rolling mill, the cross angle of the work rolls is adjusted with high precision, taking into account the size of the liner. That is, in adjusting the cross angle, the size of the liner is an important factor in adjusting the positions of the work rolls and the roll chocks.

[0008] When the cross angle is adjusted frequently, the liner receives a large load from the roll chocks and crosshead, causing friction and a change in size (shrinkage) as wear progresses. Therefore, to precisely control the position of the roll chocks, i.e., to precisely control the cross angle of the work rolls, it is necessary to measure the amount of wear on the liner and carry out repair work on the liner.

[0009] However, measuring the wear amount of the liner requires measuring the distance from a reference surface on the housing to the surface of the liner and calculating the difference between that distance and the dimension shown in the drawing. In this case, an operator or the like attaches a measuring jig to the reference surface on the housing inside the rolling mill and measures the distance between the measuring jig and the surface of the liner using a microgauge or the like. Since a rolling line that rolls the rolled material is equipped with multiple rolling mills, performing this measurement by an operator or the like requires the rolling line to be stopped for an extended period of time and also requires a great deal of human labor.

[0010] The present invention has been made in consideration of the above circumstances, and its object is to provide a measuring device that can shorten the measurement period for the amount of wear of an object to be measured and reduce the human labor required for the measurement work. [Means for solving the problem]

[0011] [1] A measuring device comprising: a pressure unit that applies pressure to an object to be measured in a direction opposite to the direction in which the object to be measured protrudes, and adjusts the position of the object to be measured; a measuring unit that measures the surface shape of the object to be measured whose position has been adjusted by the pressure unit; a calculation unit that compares the surface shape measured by the measuring unit with a predetermined standard shape to calculate a differential thickness; and a housing that holds at least the pressure unit and the measuring unit. [2] The measuring device according to [1], further comprising a pressure adjusting unit that adjusts the pressure applied to the object to be measured by the pressurizing unit. [3] The measuring device according to [1], further comprising a movement mechanism configured to enable movement of the housing. [4] The measuring device according to [2], further comprising a movement mechanism configured to enable movement of the housing. [5] The measuring device according to any one of [1] to [4], wherein the object to be measured is a liner part of a rolling mill. [6] A measurement method comprising: a pressurizing step of applying pressure to the object to be measured in a direction opposite to the direction in which the object to be measured protrudes, thereby adjusting the position of the object to be measured; a measurement step of measuring the surface shape of the object to be measured whose position has been adjusted by the pressurizing step; and a calculation step of calculating a differential thickness by comparing the surface shape measured by the measurement step with a predetermined standard shape. [7] The measurement method according to [6], wherein the pressurizing step includes a pressure adjusting step of adjusting the pressure applied to the object to be measured. [Effects of the Invention]

[0012] According to the present invention, it is possible to shorten the period of time required to measure the amount of wear of a measurement object and reduce the human labor required for the measurement work. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing an example of a schematic side cross-sectional configuration of a pair cross type rolling mill. [Figure 2]3A and 3B are diagrams illustrating an example of a schematic configuration of a reference portion and a liner portion in a head portion. [Figure 3] 1 is a diagram showing an example of a schematic configuration of a measurement device of the present invention. [Figure 4] FIG. 2 is a diagram showing a schematic configuration for measuring the surface shape of a liner portion using the measuring device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] First, a pair cross type rolling mill 20 to which the present invention can be applied will be described. Fig. 1 shows an example of a schematic side cross section of a pair cross type rolling mill 20. Specifically, Fig. 1(a) shows an example of a schematic side cross section of the rolling mill 20 as seen from the operation side (op side). Fig. 1(b) shows an example of a schematic side cross section of the rolling mill 20 as seen from the drive side (dr side).

[0015] As shown in Figure 1, a rolling mill 20 has work rolls 21, work roll chocks 22, auxiliary rolls 23, auxiliary roll chocks 24, a head portion 25, a liner portion 26, a housing 27, and a drive portion 28. The work rolls 21 roll the material to be rolled using a pair of upper and lower work rolls. The auxiliary rolls 23 support the work rolls 21 using a pair of upper and lower auxiliary rolls.

[0016] The pair cross type rolling mill 20 rotates the work rolls 21 and auxiliary rolls 23 in a direction horizontal to the plane of the drawing, thereby causing the axial angle of the upper work rolls 21 and auxiliary rolls 23 to cross the axial angle of the lower work rolls 21 and auxiliary rolls 23.

[0017] Specifically, in FIG. 1(a), the work rolls 21 and auxiliary rolls 23 arranged at the bottom are movable left and right as viewed in the drawing by drive of the drive unit 28 (see the horizontal arrow in the drawing). On the other hand, in FIG. 1(b), the work rolls 21 and auxiliary rolls 23 arranged at the bottom are restricted (fixed) in their movement left and right as viewed in the drawing. That is, the work rolls 21 and auxiliary rolls 23 arranged at the bottom are movable on the operation side of the rolling mill 20, but their movement is restricted on the drive side of the rolling mill 20. In contrast, the work rolls 21 and auxiliary rolls 23 arranged at the top are restricted in their movement on the operation side of the rolling mill 20 (see FIG. 1(a)), but are movable on the drive side of the rolling mill 20 (see FIG. 1(b)). Hereinafter, the configuration (direction) of the work roll 21 and auxiliary roll 23 in which movement in the left and right direction is possible will be referred to as the "cross side," and the configuration (direction) in which movement in the left and right direction is restricted will be referred to as the "pivot side."

[0018] The work roll chocks 22 have a cross-side work roll chock 22a and a pivot-side work roll chock 22b. The work roll chocks 22 rotatably support the work rolls 21 via bearings or other bearings, and are held inside the housing 27. The auxiliary roll chocks 24 rotatably support the auxiliary rolls 23 via bearings or other bearings, and are held inside the housing 27.

[0019] The head section 25 has a cross-side head 25a and a pivot-side head 25b. The liner section 26 has a cross-side liner 26a and a pivot-side liner 26b. The cross-side liner 26a is provided between the cross-side work roll chock 22a and the cross-side head 25a, and absorbs the load received from the cross-side work roll chock 22a, suppressing transmission of the load to the cross-side head 25a and the housing 27. The pivot-side liner 26b is provided between the pivot-side work roll chock 22b and the pivot-side head 25b, and absorbs the load received from the pivot-side work roll chock 22b, suppressing transmission of the load to the pivot-side head 25b and the housing 27.

[0020] 1, the housing 27 has a gate-shaped configuration that holds the work rolls 21 and work roll chocks 22 inside. The housing 27 is made up of a pair of frames (cross side and pivot side) that support the work rolls 21 and auxiliary rolls 23. The housing 27 is configured to be connected to the work roll chocks 22 that support the work rolls 21 via the liner portions 26 and head portions 25, as shown in FIG.

[0021] The head portion 25 (the cross-side head 25a and the pivot-side head 25b) has a reference portion 25c. The reference portion 25c is used to measure the surface shape of the measurement object (the liner portion 26) when the measurement device of the present invention is used.

[0022] Next, the configuration of the reference portion 25c and the liner portion 26 in the head portion 25 will be described with reference to the drawings. Fig. 2 is a diagram showing an example of a schematic configuration of the reference portion 25c and the liner portion 26 in the head portion 25. Fig. 2 is a diagram showing the rolling mill 20 shown in Fig. 1 with the work roll chocks 22 removed.

[0023] 2, the reference portion 25c provided on the head portion 25 has a reference surface 25d. The liner portion 26 has a liner tip portion 26c and a liner main body portion 26e. The liner tip portion 26c has a liner tip surface 26d.

[0024] When the cross angle of the pair of upper and lower work rolls 21 in the rolling mill 20 is frequently adjusted, the liner portion 26 is subjected to repeated loads from the work roll chocks 22 and the head portion 25, causing friction. In particular, the cross-side liner 26a is subjected to a large load as the drive portion 28 is driven, and is therefore prone to wear.

[0025] Specifically, wear in the liner portion 26 progresses based on the load that the liner tip portion 26c receives from the work roll chock 22 and the resistance force from the head portion 25 connected to the housing. That is, wear in the liner main body portion 26e progresses due to the influence of loads from two opposing directions. In this case, the size of the liner main body portion 26e decreases in the direction sandwiched between the liner tip portion 26c and the head portion 25 (the up-down direction in the drawing).

[0026] As mentioned above, in adjusting the cross angle in the pair cross type rolling mill 20, the size of the liner portions 26 is an important factor in adjusting the positions of the work rolls 21 and the work roll chocks 22. For this reason, it is necessary to measure the amount of wear of the liner portions 26 and to perform periodic repair work on the liner portions 26.

[0027] The measuring device of the present invention is capable of measuring the surface shape of the object to be measured, that is, the liner portion 26. When the distance between the liner tip surface 26d and the reference surface 25d is defined as distance A, the surface shape can be said to be a set of data representing the measurement values ​​of distance A at each position on the liner tip surface 26d.

[0028] For this reason, when a liner portion 26 is newly installed in the rolling mill 20, the surface shape of the liner portion 26 may be measured using the measuring device of the present invention, and after wear of the liner portion 26 has progressed by operating the rolling mill 20, the surface shape may be measured again using the measuring device of the present invention. Then, by comparing the surface shape of the liner portion 26 when newly installed with the surface shape of the liner portion 26 after wear has progressed, the amount of wear of the liner portion 26 can be determined.

[0029] Next, the configuration of the measuring device of the present invention will be described with reference to the drawings. Fig. 3 is a diagram showing an example of the schematic configuration of a measuring device 10 of the present invention. As shown in Fig. 3, the measuring device 10 has a pressurizing unit 11, a measuring unit 12, a measurement control unit 13, a calculation unit 14, and a housing 15.

[0030] The pressure applying unit 11 applies pressure to the object to be measured in a direction opposite to the direction in which the object to be measured protrudes, thereby adjusting the position of the object to be measured. In this embodiment, the object to be measured corresponds to the liner portion 26. That is, the pressure applying unit 11 applies pressure to the liner portion 26 in a direction (arrow T in FIG. 2) opposite to the direction in which the liner portion 26, which is the object to be measured, protrudes (arrow S in FIG. 2).

[0031] As described above with reference to FIG. 2, wear of the liner portion 26 in the rolling mill 20 progresses in size reduction in the direction sandwiched between the liner tip portion 26c and the head portion 25. The direction sandwiched between the liner tip portion 26c and the head portion 25 is along the same axis as the direction in which the liner portion 26 protrudes (arrow S) and the opposite direction (arrow T). Therefore, by applying pressure to the measurement object (liner portion 26) using the pressure unit 11, it is possible to reduce the gaps between the liner tip portion 26c, the liner main body portion 26e, and the head portion 25. This improves the measurement accuracy of the surface shape of the measurement object (liner portion 26).

[0032] It should be noted that the method of applying pressure to the measurement object (liner portion 26) by the pressure unit 11 is not limited, as long as it is possible to close the gaps between the components, and may include pressure using a hydraulic jack, pressure using a screw, etc. Furthermore, the pressure unit 11 may apply pressure to a partial area of ​​the surface of the measurement object (liner portion 26).

[0033] The measuring unit 12 measures the surface shape of the measurement object (liner portion 26) whose position has been adjusted by the pressurizing unit 11. Specifically, the measuring unit 12 first measures the distance between the reference surface 25d in the reference portion 25c and the measuring unit 12. Next, the measuring unit 12 measures the distance between each position on the liner tip surface 26d in the liner tip portion 26c and the measuring unit 12. The difference between these two distances is then calculated to obtain the surface shape of the measurement object (liner portion 26). The calculation unit 14, which will be described later, can then determine the amount of wear of the liner portion 26 based on the surface shape and the standard shape. Here, the "amount of wear" corresponds to the amount of wear relative to the drawing dimensions (the dimensions of the liner portion 26 where wear has not progressed).

[0034] The measurement unit 12 may simultaneously measure the distance between the reference surface 25d and the measurement unit 12, and the distance between each position on the liner tip surface 26d and the measurement unit 12. In this case, the measurement unit 12 may perform measurements including the reference surface 25d and the liner tip surface 26d within the measurement field of view. As long as the measurement unit 12 can measure the distance between the reference surface 25d and the measurement unit 12 and the distance between the liner tip surface 26d and the measurement unit 12, any measurement method may be used, such as measurement using a 3D scanner, laser measurement useful for distance measurement, or non-contact measurement. When a 3D scanner is used in the measurement unit 12, the scanning direction and position may be controlled by the measurement control unit 13. Using a 3D scanner in the measurement unit 12 can further shorten the time required to measure the surface shape of the object to be measured (the liner portion 26), thereby facilitating maintenance and other tasks.

[0035] The calculation unit 14 compares the surface shape of the object to be measured (liner portion 26) measured by the measurement unit 12 with a preset standard shape to calculate the differential thickness. Here, the "standard shape" may be the surface shape measured using the measuring device of the present invention when a new liner portion 26 is installed in the rolling mill 20. Alternatively, for the purpose of precise adjustment of the cross angle, individual values ​​may be applied to the "standard shape" based on the specifications of the configuration of the work roll chocks 22, head portion 25, etc.

[0036] The "difference in thickness" calculated by the calculation unit 14 corresponds to the amount of wear of the liner portion 26. More specifically, the "difference in thickness" corresponds to the amount of wear lost in the liner main body 26e due to wear. Then, by inserting an additional shim member or the like into the liner main body 26e based on the "difference in thickness" calculated using the measuring device of the present invention, the surface shape of the object to be measured (liner portion 26) can be repaired to the "standard shape." Therefore, precise adjustment of the cross angle in the rolling mill 20 can be maintained.

[0037] The housing 15 holds at least the pressing unit 11 and the measuring unit 12. As will be described later in connection with a measurement method using the measuring device of the present invention, the measuring device 10 is sized to be able to enter the space inside the rolling mill 20 from which the work roll chocks 22 have been removed in order to measure the liner portion 26, which is the object to be measured. In other words, the housing 15 is smaller than the size of the sides of the two work roll chocks 22 (cross-side work roll chock 22a and pivot-side work roll chock 22b) provided above and below.

[0038] This makes it possible to insert the measuring device 10 into the space where the upper and lower work rolls 21 and work roll chocks 22 were installed, eliminating the need for personnel to enter the space and perform manual work to measure the wear amounts of all liner portions 26. In other words, the maintenance period for the rolling line can be shortened, and the human labor required for measurement work can be reduced.

[0039] The pressure unit 11 preferably further includes a pressure adjustment unit 17 that adjusts the pressure applied to the measurement object (liner portion 26). The wear progress of the liner portion 26, which is the measurement object, varies depending on its location. For this reason, for example, the pressure may be adjusted to be low on the pivot side, where wear progresses slowly, and high on the cross side, where wear progresses quickly. Furthermore, as wear progresses in the liner portion 26, gaps form between the components in the direction sandwiched between the liner tip portion 26c and the head portion 25, and lubricant penetrates into these gaps. Therefore, by adjusting the pressure, the lubricant can be easily pushed out of the gap, maintaining measurement accuracy.

[0040] The pressure adjustment by the pressure adjustment unit 17 may be performed by any method, such as an adjustment method based on a pressure value measured by a pressure gauge, or an adjustment method based on a preset rotation amount of a hydraulic jack.

[0041] It is preferable that the measuring device 10 further includes a moving mechanism 16 that enables movement of the housing 15. Specifically, in the rolling mill 20 from which the work roll chocks 22 have been removed, it is preferable that the moving mechanism 16 be configured to be able to automatically move back and forth within the space where the work roll chocks 22 were installed. It is preferable that the moving mechanism 16 be configured to be movable between the cross-side housing 27 and the pivot-side housing 27.

[0042] Here, the rolling mill 20 is provided with a large number of liner portions 26 in the depth direction of the drawing in Fig. 1. In the liner portions 26, the load applied to adjust the actual cross angle differs depending on the position where the liner portion 26 is arranged. For this reason, the amount of wear in all the liner portions 26 is not uniform, and it is necessary to measure the amount of wear in the large number of liner portions 26 individually.

[0043] Therefore, by providing the movement mechanism 16, the measuring device 10 can be automatically moved forward and backward within the space where the upper and lower work rolls 21 and the work roll chocks 22 were installed. In other words, the maintenance period for the rolling line can be further shortened.

[0044] The configuration of the movement mechanism 16 is not critical as long as it allows the measuring device 10 to move back and forth within the space previously occupied by the upper and lower work rolls 21 and work roll chocks 22. Furthermore, to facilitate smooth movement of the measuring device 10 by the movement mechanism 16, a rail or other structure for use in moving the measuring device 10 may be provided within the space previously occupied by the lower work roll chock 22.

[0045] Next, measurement of the surface shape of a measurement object using the measuring device of the present invention will be described with reference to the drawings. Fig. 4 is a diagram showing a schematic configuration in which the surface shape of the liner portion 26 is measured using the measuring device 10 of the present invention.

[0046] When measuring the liner portion 26, which is the object to be measured, first, the upper and lower work rolls 21 and work roll chocks 22 are removed from the rolling mill 20. Then, as shown in Figure 4, the measuring device 10 is inserted into the space where the upper and lower work rolls 21 and work roll chocks 22 had been installed so that it can move back and forth.

[0047] The measuring device 10 measures the surface shape of each liner portion 26 while moving in the depth direction of the rolling mill 20. The measured surface shape is then compared with a preset standard shape to calculate a differential thickness corresponding to the amount of wear of each liner portion 26.

[0048] The surface shape and differential thickness (amount of wear) measured by the measuring device 10 may be transmitted to a separately installed host center or the like and recorded as information relating to each individual liner portion 26. Then, each liner portion 26 may be repaired by personnel or the like in accordance with the recorded information on the differential thickness (amount of wear) relating to each individual liner portion 26.

[0049] As shown in Fig. 4, the measuring device 10 of the present invention is movable within the space where the two work roll chocks 22 (the cross-side work roll chock 22a and the pivot-side work roll chock 22b) installed above and below are installed. This allows the measurement objects to cover all of the cross-side liners 26a and pivot-side liners 26b. Furthermore, a single movement within the space of the rolling mill 20 allows the surface shapes (amounts of wear) of all of the liner portions 26 to be measured. This shortens the time required to measure the amount of wear of the liner portions 26 and reduces the human labor required for the measurement work.

[0050] From the above, the surface shape of a measurement object may be measured by performing the measurement method of the present invention. Specifically, the measurement method may include a pressurizing step of pressurizing the measurement object in a direction opposite to the protruding direction of the measurement object and adjusting the position of the measurement object, a measurement step of measuring the surface shape of the measurement object whose position has been adjusted by the pressurizing step, and a calculation step of comparing the surface shape measured by the measurement step with a preset standard shape to calculate a differential thickness. Furthermore, the pressurizing step preferably includes a pressure adjustment step of adjusting the pressure applied to the measurement object. [Example]

[0051] Next, an example will be described in which the surface shape (amount of wear) of a liner in a rolling mill was measured using the measuring device of the present invention. In carrying out the example, the rolling mill 20 shown in Figure 1 was used as the target, and the upper and lower work rolls 21 and the work roll chocks 22 were removed from the rolling mill 20 in advance.

[0052] First, as a comparative example, the surface shapes of multiple liner portions 26 installed in a single rolling mill 20 were measured as a job performed by multiple workers. Specifically, workers entered the housing 27 of the rolling mill 20, attached a measuring jig to the reference surface 25d of the reference portion 25c of the head portion 25, and measured the distance between the measuring jig and the liner tip surface 26d with a microgauge. Thereafter, the amount of wear in the liner portion 26 was obtained based on the difference in thickness between the measured value and the drawing dimensions of the liner portion 26 when it was newly installed in the head portion 25. In the comparative example, it took three hours as a job performed by five workers to measure the amount of wear in all of the liner portions 26.

[0053] Next, as an example of the invention, the measuring device of the present invention was used to measure the surface shapes of multiple liner portions 26 provided in a single rolling mill 20. A three-dimensional scanner was applied to the measuring section 12 of the measuring device 10. The measuring device 10 was inserted so that it could move forward and backward within the space in which the upper and lower work rolls 21 and work roll chocks 22 were installed. The measuring device 10 was then moved in the depth direction of the rolling mill 20 while measuring the surface shapes of each liner portion 26, and the measured surface shapes were compared with a predetermined standard shape to calculate the differential thickness corresponding to the amount of wear of all the liner portions 26.

[0054] In the example of the invention, the surface shape of the liner portion 26 was measured while applying pressure to the liner portion 26 with the pressure unit 11 in the direction opposite to the direction in which the liner portion 26 protrudes, thereby improving the measurement accuracy. Furthermore, the surface shape of each liner portion 26 could be measured while moving the measuring device 10 in the depth direction of the rolling mill 20. As a result, in the implementation of the example of the invention, it was possible to complete the measurement of the surface shape (amount of wear) of all the liner portions 26 in 15 minutes as the work of a single person. Therefore, it was confirmed that by using the measuring device of the present invention, the time required to measure the amount of wear of the liner portion 26 can be shortened and the human labor required for the measurement work can be reduced. [Explanation of symbols]

[0055] 10. Measuring equipment 11 Pressurizing section 12 Measuring part 13 Measurement control section 14 Arithmetic section 15 Case 16 Moving mechanism 17 Pressure adjustment section 20. Rolling Mill 21 Work Roll 22 Work roll chock 22a Cross side work roll chock 22b Pivot side work roll chock 23 Auxiliary Roll 24 Auxiliary roll chock 25 Head 25a Cross side head 25b Pivot side head 25c Reference section 25d Reference plane 26 Liner section 26a cross side liner 26b Pivot side liner 26c liner tip 26d Liner tip surface 26e Liner body 27 Housing 28 Drive unit

Claims

1. a pressure unit that applies pressure to the object to be measured in a direction opposite to the direction in which the object to be measured protrudes, and adjusts the position of the object to be measured; a measurement unit that measures the surface shape of the measurement object whose position has been adjusted by the pressure unit; a calculation unit that compares the surface shape measured by the measurement unit with a predetermined standard shape to calculate a differential thickness; a housing for holding at least the pressurizing unit and the measuring unit; A measuring device comprising:

2. The measuring device according to claim 1 , further comprising a pressure adjusting unit that adjusts the pressure applied to the measurement object by the pressurizing unit.

3. The measuring device according to claim 1 , further comprising a movement mechanism that enables the housing to be moved.

4. The measuring device according to claim 2 , further comprising a movement mechanism that enables the housing to be moved.

5. 5. The measuring device according to claim 1, wherein the object to be measured is a liner portion of a rolling mill.

6. a pressurizing step of applying pressure to the measurement object in a direction opposite to a direction in which the measurement object protrudes, thereby adjusting the position of the measurement object; a measuring step of measuring a surface shape of the measurement object whose position has been adjusted by the pressing step; a calculation step of comparing the surface shape measured in the measurement step with a predetermined standard shape to calculate a difference thickness; A measurement method comprising:

7. The measurement method according to claim 6 , wherein the pressurizing step includes a pressure adjusting step of adjusting the pressure of the pressurization applied to the measurement object.

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