Detection sample plate and design method thereof

Abstract

The invention belongs to the technical field of ocean engineering, and particularly relates to a detection sample plate and a design method thereof.The detection sample plate is used for detecting a bent plate, the bent plate is configured to be a transition area of a plate body, the bent position of the bent plate is an arc, the radius of the arc is R, an included angle formed by the arc center line of the bending part and a horizontal line perpendicular to the center line of the bending plate is a, and the detection sample plate is characterized in that the downstream outer edge of the detection sample plate is in an elliptic arc shape, the length ratio of a short axis to a long axis of an ellipse formed by the elliptic arc shape is sin a, and the length of the short axis is 2R. The device is reasonable in design principle and simple in structure, and the measured value is accurate to + / -1mm.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering technology, and more specifically, to a detection sample and a design method thereof. Background Art

[0002] like Figures 1-2 As shown in the cross section of the cargo hold of a crude oil and product oil tanker, the angle between the inner bottom plate 24 and the ramp plate 23 is mostly designed to be 135 degrees. The original design form is that the inner bottom plate 24, the ramp plate 23 and the longitudinal girder 25 are assembled and welded in three centers. The specific node form is shown in Figure 1 After optimizing the process, the inner bottom plate 24 and the ramp plate 24 are changed to a flat plate by bending, and the bending angle (the angle formed by the two flat plates) is 135 degrees, which can save the workload of welding the inner bottom plate 24 and the ramp plate 23, such as Figure 3 As shown in the figure, the inner bottom plate 24 and the ramp plate 23 are designed as a single plate by bending and forming, which saves welding materials and assembly welding time compared with the traditional plate welding method. Figure 4 As shown, in order to improve the manufacturing accuracy of the bending plate 18, the bending plate 18 needs to be tested after bending, and an angle template is used for testing. Figures 5 to 7 As shown, a stamping jig is used for press bending, and the pressing is completed at room temperature. The arc curve of the cross-section of the jig used by the hydraulic press is a perfect arc. The upper jig 29 is used to squeeze the bending plate (flat plate state) into the lower jig 30 during press bending. After the bending plate 18 is fitted with the jig mold surface, the upper jig 29 is released. After the bending plate 18 rebounds after the internal stress on the lower jig 30, a stable bending plate shape value of the bending plate is obtained. Due to the shrinkage of the longitudinal linear dimensions of the cargo hold compartment in the transition area between the bow and stern of the hull, the arc center line 19 and the plate edge line 20 of the bending plate 18 are not parallel to the center of the hull. In this case, after the bending plate 18 is formed in the same mold, when the test template 16 is placed parallel to the rib to test the fit of the bending plate 18, the arc part of the test template 16 needs to be made into an elliptical arc. The test template directly made of a positive arc with a designed radius does not meet the test requirements. The manufacturing accuracy of the test template 16 has exceeded the tolerance standard, so it is necessary to use an elliptical arc to redesign the template to meet the test requirements. Summary of the invention

[0003] In order to solve the problem that the test sample made by cutting the material of the designed radius of the positive arc has a manufacturing accuracy that exceeds the tolerance standard and cannot meet the test requirements of the fit of the hull transition zone, the present invention provides a test sample. The test sample designed by the method of the present invention can be used for the test of the fit of the bending plate in different transition areas of the hull. The present invention has a simple structure and the measurement accuracy can be accurate to ±1mm.

[0004] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0005] In a first aspect of the present invention, a method for designing a test sample is provided, which is used to detect a bending plate, wherein the bending plate is configured as a transition zone of a plate body, the bending portion of the bending plate is an arc, the arc center angle of the arc is b, the arc radius is R, and the angle formed by the arc center line of the bending portion and a horizontal line perpendicular to the center line of the plate body is a. The method for designing the test sample comprises the following steps:

[0006] S1. Draw a circle with radius R with point O as the center, draw the horizontal diameter and vertical diameter of the circle, and the intersection of the vertical diameter and the bottom of the circle is the fifth intersection point; draw the third parallel line of the tangent of the circle through the fifth intersection point to the right side of the circle;

[0007] S2. Make a first radius and a second radius at the lower left part of the perfect circle. The intersection of the first radius and the perfect circle is the first intersection, the intersection of the second radius and the perfect circle is the second intersection, the acute center angle formed by the first radius and the vertical diameter is angle b, and the second radius bisects the acute center angle formed by the first radius and the vertical diameter;

[0008] S3, draw a first parallel line parallel to the horizontal diameter through the first intersection toward the outside of the circle, and draw a second parallel line parallel to the horizontal diameter through the second intersection toward the outside of the circle; draw a first perpendicular line and a second perpendicular line to the tangent of the circle through the two intersections of the circle and the horizontal diameter respectively;

[0009] S4, with point O as the rotation point, draw a third diameter of the perfect circle in the direction of a degree clockwise on the vertical diameter, extend the two ends of the third diameter to intersect the first perpendicular line and the second perpendicular line to obtain the first straight line segment; with point O as the rotation point, rotate the first straight line segment to be perpendicular to the vertical diameter, draw an ellipse with the rotated first straight line segment as the major axis, the horizontal diameter as the minor axis, and point O as the center; the intersection of the ellipse and the first parallel line is the third intersection point, and the intersection of the ellipse and the second parallel line is the fourth intersection point; with the third intersection point as the rotation point, draw a second straight line segment outside the ellipse in the direction of b degrees clockwise on the first parallel line;

[0010] S5, intercepting a first multi-segment line formed by the second straight line segment, the ellipse arc segment between the third intersection point and the fifth intersection point on the ellipse, and the third parallel line;

[0011] S6. Connect two endpoints of the first polyline to obtain a detection template drawing, and make a detection template according to the detection template drawing.

[0012] In a preferred embodiment, the line segment connecting the two endpoints of the first polyline is a polyline or a straight line segment.

[0013] In a preferred embodiment, the lengths intercepted by the second straight line segment and the third parallel line are equal.

[0014] According to the second aspect of the present invention, a detection template produced by the above-mentioned design method is provided, wherein the downstream outer edge of the detection template has an elliptical arc shape, the length ratio of the minor axis and the major axis of the ellipse having the elliptical arc shape is sina, and the length of the minor axis is 2R; the elliptical arc has a first endpoint, and the first endpoint is configured as the intersection of the minor axis of the ellipse and the ellipse; the outer edge from the first endpoint to the upstream of the detection template is configured to be along the tangent direction of the elliptical arc at the first endpoint.

[0015] In a preferred embodiment, the angle formed by the ellipse and the major axis at the second endpoint is b.

[0016] In a preferred embodiment, a hand-held hole is provided upstream of the detection sample; and a side surface of the hand-held hole has an arc that bends toward between the hand-held holes.

[0017] In a preferred embodiment, the upstream of the detection sample is configured in a trapezoidal shape.

[0018] The beneficial effects of the present invention are:

[0019] This design method realizes the design method of the bending accuracy detection sample when the center of the bending plate in the bow and stern area is not parallel to the centerline of the hull. When the jig design form is fixed, there is a deviation in the bending fit detection of the bending plate in the bow and stern transition area. The main reason for the problem is the deviation in the design of the detection sample. This sample design method optimizes the design form of the bending plate detection sample in the bow and stern transition area. The sample designed in this form can meet the on-site detection requirements, and the detection results are more accurate and precise. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the bottom plan view in the transition area of ​​the forward part of the cargo hold;

[0021] Figure 2 It is a schematic diagram of the original node form of the inner bottom plate and the slope bottom plate;

[0022] Figure 3 It is a schematic diagram of the new node form between the inner bottom plate and the slope bottom plate;

[0023] Figure 4 This is a schematic diagram of the present invention using a test sample to test a bending plate ( Figure 1 AA section view);

[0024] Figure 5 It is a schematic diagram of the planar material of the bent plate;

[0025] Figure 6 It is a three-dimensional schematic diagram of the bent plate after forming;

[0026] Figure 7 It is a schematic diagram of sheet metal bending;

[0027] Figure 8 It is a schematic diagram of the design principle of the detection sample of the present invention.

[0028] In the figure, 1, a perfect circle (the radius of the perfect circle is equal to the bending radius); 2, a horizontal diameter; 201, a first straight line segment (the length is equal to the major axis); 3, a vertical diameter; 4, a first perpendicular line; 5, a second perpendicular line; 6, an ellipse; 7, a second intersection point (the arc center line projection accumulation point); 8, a fifth intersection point (the R stop line projection accumulation point); 9, a first intersection point (the R stop line projection accumulation point); 10, a second parallel line (the arc center line projection accumulation point horizontal lead line); 11, a first parallel line (the R stop line projection accumulation point horizontal lead line); 12, a third parallel line (the R stop line projection accumulation point horizontal lead line); 13 , the fourth intersection point (the intersection point of the horizontal lead line of the arc centerline projection accumulation point and the elliptical arc); 14. The third intersection point (the intersection point of the horizontal lead line of the R stop line projection accumulation point and the elliptical arc); 15. The second straight line segment (the straight line segment with the same angle as the ramp plate); 16. Test sample; 17. The contour line of the hull rib plate; 18. The bending plate; 19. The arc centerline; 20. The plate seam line; 21. The centerline; 22. The R stop line; 23. The inner bottom plate; 24. The ramp plate; 25. The longitudinal girder; 26. The bending radius; 27. The upper roller of the hydraulic press; 28. The lower roller of the hydraulic press; 29. ​​The upper jig; 30. The lower jig; AR stop. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0030] Use the rotation method to find the length of the major axis and minor axis of the ellipse end face formed by a right cylinder beveled at an angle of a°. The specific operation method is: draw a perpendicular line through the first and last endpoints of the right circle diameter, rotate the diameter through the center of the right circle and parallel to the perpendicular line clockwise for a degree with the center of the circle as the axis point, extend the oblique line segment to intersect with the two perpendicular lines, and then rotate this oblique line segment counterclockwise for a degree to become a straight line segment. Use this straight line segment as the major axis, the right circle diameter perpendicular to this line segment as the short line segment as the short axis, and draw an ellipse. The length of the major axis can also be calculated by mathematical methods. Using the known parameters: the design radius R of the bending plate, the angle a formed by the arc center line of the bending plate in the transition zone between the fore and stern and the rib position line of the hull, find the major axis and minor axis of the ellipse. According to the trigonometric function: 2R / X=cos(90°-a), calculate X=2R / cos(90°-a). R and ∠a are known parameters, and the major axis X of the ellipse can be found. The minor axis is 2R. With the known lengths of the major and minor axes, a perfect circle with a radius of R and an ellipse with a major axis of X and a minor axis of 2R is drawn on the drawing software CAD. The central angle b of the arc of the bending plate is known, and the central angle point 7 is the midpoint of the arc with two R end points, that is, the straight line O7 is the angular bisector of the central angle. The arc center point 7 on the arc is translated to the newly drawn elliptical arc to form a new intersection point 14, and the R end point 9 is drawn with a horizontal line intersecting the elliptical arc at point 14; a sample hand-held hole is designed on the template, which is used as a hand-held hole for holding the sample when testing the curvature of the bent plate; after the elliptical arc is determined, a short straight line is made at the R end point and the arc center point on the elliptical arc as a detection mark on the template. The bending plate is used as a three-center alignment node in different positions of the cargo hold or other steel structures of the hull, all within the protection range.

[0031] like Figure 8 As shown, a design method for a detection sample includes the following steps:

[0032] S1. Draw a perfect circle 1 with point O as the center, and draw horizontal diameter 2 and vertical diameter 3 on the perfect circle 1. The radius of the perfect circle is R.

[0033] S2. Draw the first radius and the second radius on the left half of the lower semicircle of the perfect circle 1. The angle between the first radius and the central angle of the vertical diameter 3 is b. The second radius bisects the central angle between the vertical diameter 3 and the first radius. The intersection of the first radius and the perfect circle 1 is the first intersection 9, and the intersection of the second radius and the perfect circle 1 is the second intersection 7. Draw parallel lines (the first parallel line 11 and the second parallel line 10) parallel to the horizontal radius 2 through the first intersection 9 and the second intersection 7.

[0034] S3, draw tangents (first perpendicular line 4 and second perpendicular line 5) of perfect circle 1 through the two intersections of horizontal diameter 2 and perfect circle 1. Draw a third diameter on perfect circle 1, the central angle between the third diameter and vertical diameter 3 is a, extend the third diameter to make first straight line segment 201, the two endpoints of first straight line segment 201 are the intersections of first straight line segment 201 and first perpendicular line 4 and second perpendicular line 5, take point O as the axis point, rotate first straight line segment 201 to horizontal, take first straight line segment 201 as the major axis of ellipse, take vertical diameter 3 as the major axis of ellipse, and draw ellipse 6. The intersection of ellipse 6 and first parallel line 11 is third intersection 14 (i.e., the second endpoint of the test sample), and the intersection of ellipse 6 and second parallel line 10 is fourth intersection 13.

[0035] S4, with the third intersection 14 as the axis point, rotate the second parallel line 10 clockwise by angle b to obtain the second straight line segment 15. The intersection of the vertical diameter 3 and the lower half of the perfect circle 1 is the fifth intersection 8 (i.e., the first endpoint of the test sample), and the third parallel line 12 is drawn to the right with the fifth intersection as the starting point.

[0036] S5. In the figure drawn in steps S1 to S4, intercept the first polyline formed by the second straight line segment 15-the third intersection point 14-the fifth intersection point 8-the third parallel line 12, and design the detection template 16 with the first polyline as the reference detection end face of the detection template 16.

[0037] S6. Draw three lines with the endpoints of the second straight line segment 15 and the third parallel line 12 as starting points and end points respectively to form an auxiliary detection end surface (upstream of the detection template 16). Preferably, the shape of the auxiliary detection end surface is a trapezoid.

[0038] S7, draw a hand-held hole 23 in the middle of the auxiliary detection end surface, and then make a detection template 16 according to the drawn pattern.

[0039] The detection template designed in the above scheme can detect the bow and stern transition area that forms a certain angle with the hull centerline 21, and the angle detection template 16 of the inner bulkhead shell bending plate 18 can accurately detect the fit of the bending plate 16.

[0040] Example 1

[0041] A detection template is used to detect a bending plate 18, wherein the bending plate 18 is configured as a transition zone of a plate body, the bending part of the bending plate is an arc, the arc radius is R, the angle formed by the arc center line of the bending part and a horizontal line perpendicular to the center line 21 of the plate body is a, the downstream outer edge of the detection template 16 has an elliptical arc shape, the length ratio of the minor axis to the major axis of the ellipse having the elliptical arc shape is sin a, and the minor axis length is 2R.

[0042] The elliptical arc has a first endpoint, and the first endpoint is configured as an intersection point between the minor axis of the ellipse and the ellipse.

[0043] The angle between the second end point and the outer edge direction upstream of the detection sample 16 and the long axis is b.

[0044] The angle formed by the ellipse and the major axis at the second endpoint is b.

[0045] The outer edge from the second end point to the upstream of the detection template 16 is configured to be along the tangent direction of the elliptical arc at the second end point.

[0046] The side surfaces of the hand-holding holes 23 have an arc that curves toward between the hand-holding holes 23 .

[0047] The upstream of the detection sample 16 is configured in a trapezoidal shape.

[0048] The present invention discloses a method for calculating the actual length of the arc extension of the bow and stern transition zone with a certain angle to the center line of the hull, accurately calculating the ellipse formed by the angle formed by the arc center line marked in the hull design drawing and the hull center line, and accurately determining the actual position of the arc center line and the R stop line on the ellipse arc, and designing a design method for a bow and stern transition zone bending angle detection plate template for angle detection parallel to the rib plate. By this method, a detection template for the bow and stern transition zone with the arc center line and the R stop line of the bending plate can be simply designed.

[0049] Example 2

[0050] like Figure 8 As shown in the figure, in view of the characteristics that the bending plates in the bow and stern transition area and the bending plates in the parallel body area are pressed with the same perfect circular mold, and the fit of the bending plates needs to be detected in a way parallel to the hull ribs during detection, the sample designed with a perfect circular arc is not applicable in the bow and stern areas. By using the method of lofting and unfolding to obtain the actual circular arc of the bending plate in the transition area with a certain angle to the centerline, a detection sample is designed. The specific steps are as follows:

[0051] 1. If Figure 3 As shown, Figure 3 Draw a perfect circle 1 with the bending radius R of the bending plate marked in the figure;

[0052] 2. Draw a horizontal diameter 2 in the horizontal direction and a vertical diameter 3 in the vertical direction on the perfect circle 1;

[0053] 3. Draw the first perpendicular line 4 and the second perpendicular line 5 through the two intersection points of the horizontal diameter 2 and the perfect circle 1;

[0054] 4. According to Figure 8The angle value b of the central angle of the arc of the bending plate 16 is given in the figure. Two radius lines are made, O8 and O9, so that the angle ∠8O9 is equal to b degrees; through the center point O, make its angle bisector O7, and the second intersection point 7 is the intersection point of the second radius and the arc of the perfect circle 1.

[0055] 5. With the center O of the circle 1 as the axis point, rotate the horizontal diameter 2 of the circle 1 counterclockwise by an angle of a degree; the vertical diameter 2 after the angle is extended intersects the first perpendicular line 4 and the second perpendicular line 5, generating a first straight line segment 201;

[0056] 6. With the center O of the circle as the axis point, rotate the first straight line segment 201 clockwise, so that the first straight line segment 201 is in a horizontal state, and draw an ellipse 6 with the first straight line segment 201 as the major axis and the vertical diameter 3 as the minor axis;

[0057] 7. Draw the arc center point (second intersection point 7), R end point (fifth intersection point 8) and R end point (first intersection point 9) on circle 1:

[0058] 8. Draw a second horizontal line 10 with the arc center point (second intersection point 7) as the endpoint, draw a first horizontal line 11 and a third horizontal line 12 with the R end point (fifth intersection point 8 and first intersection point 9) as the endpoints, the first horizontal line 11 and the third horizontal line 12 intersect the ellipse 6, and the intersection points are the fourth intersection point 13 and the third intersection point 14 respectively;

[0059] 9. With the third intersection 14 as the axis point, rotate the first horizontal straight line 11 clockwise. After rotating b degrees, the line segment becomes the second straight line segment 15;

[0060] 10. A polyline is formed, including the second straight line segment 15 (straight line segment) - the third intersection point 14 (curve point) - the fourth intersection point 13 (curve point) - the fifth intersection point 8 (curve point) - the third horizontal line 12 (straight line segment). The polyline is used as the reference detection end face of the template to design the detection template. The bow and stern transition areas that form a certain angle with the centerline of the hull can be detected. The inner bulkhead shell plate bending plate angle detection template can accurately detect the fit of the bending plate.

[0061] 11. Draw the radius, arc center point (second intersection point 7) and R end point (fifth intersection point 8 and first intersection point 9) of the test template 16 at a ratio of 1:1;

[0062] 12. The actual length of the new polyline constitutes the actual curve surface of the sample detection edge; a long cylindrical hole is designed in the upper part of the sample as the holding part when using the sample for detection, forming a complete sample cutting design.

[0063] This method is suitable for the design of templates with bending plate angles in different areas and transition areas with different angles to the center line.

[0064] The invention has reasonable design principle, simple structure and the measurement value is accurate to ±1mm.

[0065] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for designing a test sample, for testing a bending plate (18), wherein the bending plate (18) is configured as a transition zone of a plate body, the bending portion of the bending plate is an arc, the arc center angle of the arc is b, the arc radius is R, and the angle formed by the arc center line of the bending portion and a horizontal line perpendicular to the center line (21) of the plate body is a, characterized in that: The design method of the test sample includes the following steps: S1. Draw a circle (1) with a radius of R with point O as the center, draw the horizontal diameter (2) and the vertical diameter (3) of the circle (1), and the intersection of the vertical diameter (3) and the bottom of the circle (1) is the fifth intersection (8); draw a third parallel line (12) that is a tangent to the circle (1) through the fifth intersection (8) toward the right side of the circle (1); S2. Make a first radius and a second radius at the lower left part of the perfect circle (1), the intersection point of the first radius and the perfect circle (1) is the first intersection point (9), the intersection point of the second radius and the perfect circle (1) is the second intersection point (7), the acute center angle formed by the first radius and the vertical diameter (3) is angle b, and the second radius bisects the acute center angle formed by the first radius and the vertical diameter (3); S3, draw a first parallel line (11) parallel to the horizontal diameter (2) through the first intersection (9) toward the outside of the circle (1), and draw a second parallel line (10) parallel to the horizontal diameter (2) through the second intersection (7) toward the outside of the circle (1); draw a first perpendicular line (4) and a second perpendicular line (5) that are tangents to the circle (1) through the two intersections of the circle (1) and the horizontal diameter (2); S4, with point O as the rotation point, rotate the vertical diameter (3) in the direction of a degree clockwise to make the third diameter of the circle (1), extend the two ends of the third diameter to intersect the first perpendicular line (4) and the second perpendicular line (5) to obtain the first straight line segment (201); with point O as the rotation point, rotate the first straight line segment (201) to be perpendicular to the vertical diameter (3), use the rotated first straight line segment (201) as the major axis, the horizontal diameter (2) as the minor axis, and draw an ellipse (6) with point O as the center; the intersection point of the ellipse (6) and the first parallel line (11) is the third intersection point (14), and the intersection point of the ellipse (6) and the second parallel line (10) is the fourth intersection point (13); with the third intersection point (14) as the rotation point, make a second straight line segment (15) outside the ellipse (6) in the direction of b degrees clockwise on the first parallel line (11); S5, intercepting a first multi-segment line formed by the second straight line segment (15), the elliptical arc segment between the third intersection point (14) and the fifth intersection point (8) on the ellipse (6), and the third parallel line (12); S6. Connect two endpoints of the first polyline to obtain a detection template drawing, and make a detection template according to the detection template drawing.

2. The design method of the detection template according to claim 1, characterized in that: The line segment connecting the two endpoints of the first polyline is a polyline or a straight line segment.

3. The design method of the detection template according to claim 1, characterized in that: The second straight line segment (15) and the third parallel line (12) have the same length.

4. A test sample made by the design method of claim 1, characterized in that: The downstream outer edge of the detection sample (16) has an elliptical arc shape, the length ratio of the short axis to the long axis of the ellipse having the elliptical arc shape is sina, and the length of the short axis is 2R; the elliptical arc shape has a first endpoint, and the first endpoint is configured as the intersection of the short axis of the ellipse and the ellipse; The outer edge from the first end point to the upstream of the detection sample (16) is configured to be along the tangent direction of the elliptical arc at the first end point.

5. The detection sample according to claim 4, characterized in that: The angle formed by the ellipse and the major axis at the second endpoint is b.

6. The detection sample according to claim 4, characterized in that: The detection sample (16) has a hand-held hole (23) upstream; the side surface of the hand-held hole (23) has an arc that bends toward the hand-held holes (23).

7. The detection sample according to any one of claims 4 to 6, characterized in that: The upstream of the detection sample (16) is configured in a trapezoidal shape.

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