WO2016008095A1

WO2016008095A1 - Method for measuring wall thickness of large-diameter hot extruded three-way pipe

Info

Publication number: WO2016008095A1
Application number: PCT/CN2014/082242
Authority: WO
Inventors: 杨顺伟
Original assignee: 杨顺伟
Priority date: 2014-07-15
Filing date: 2014-07-15
Publication date: 2016-01-21
Also published as: CN104780986A

Abstract

A method for measuring the wall thickness of a large-diameter hot extruded three-way pipe, comprising: measuring an actually produced hot extruded three-way pipe fitting, summarizing a rule for a change in wall thicknesses thereof at different positions, and establishing a model of the wall thickness of the large-diameter hot extruded three-way pipe, thus avoiding the weakness that engineering calculations and a predicted bursting pressure computer simulation are disadvantageous as a result of the complex arrangement of wall thicknesses in a hot extruded three-way pipe.

Description

Method for measuring wall thickness of large diameter hot extrusion forming three-way

Technical field

The invention belongs to the technical field of pipe wall thickness evaluation and calculation research, and particularly relates to a method for measuring the wall thickness of a large-diameter hot extrusion forming three-way. Background technique

In the long-distance oil and gas pipeline construction, in order to meet the needs of sub-transmission, redirection, measurement, etc., on-site construction such as station yards, valve rooms and gas stations often requires a large number of large-diameter pipe fittings such as elbows and tees. For the hot extruded tee fitting, the structural strength of the tee strongly depends on the radius of curvature R of the branch and the main root and the wall thickness t of the shoulder due to the unique circular arc transition structure of the branch pipe and the main pipe root. ANS I B16. 9 The pipe specification proposes a range of pipe element dimensional requirements. The tee mainly includes the height of the main pipe and the height of the branch pipe above the main line of the main pipe, and the wall thickness of the outer diameter and the end and the size of the welding groove, but there is no requirement for the size and overall shape of the transition of the main pipe and the branch pipe. The relevant regulations of China's petrochemical industry also basically follow the above provisions. In fact, different manufacturers, different production processes, and different specifications of the hot extrusion tee of different specifications produced by different molds are not exactly the same, especially the wall thickness and the radius of curvature of the main branch transition, and these two The parameters have a large influence on the strength of the pipe. Therefore, the key dimensions of the large-diameter hot-extrusion tee are effectively measured and summarized, the change rule is found, the database of the actual hot-extrusion tee size and error range is established, and the quality supervision of the large-diameter hot-extrusion tee is Control is of great significance.

The existing literature indicates that there is no relevant measurement method and technical index that can truly reflect the actual size of each part of the equal-diameter and different-diameter hot-extrusion tee with a specification of Φ 900mm or more. Only the results of Φ 356mm X 55 mm welding high pressure equal diameter three-way burst pressure are compared with the actual burst pressure results. Compared. The equal-diameter tee is a welded high-pressure tee, and the thickness of each of the tees of the tee is relatively uniform, which can be well predicted.

Therefore, according to the characteristics of the forming process of hot extrusion tee, based on the actual measurement of the variation law of the wall thickness of the hot extrusion forming tee, the key parts of the hot extrusion forming tee are established according to the variation law of the wall thickness of the three-way pipe diameter. Wall thickness database. In order to solve the problem that the thickness of the hot-extruded tee is different, and the theoretical value after the analysis differs greatly from the measured value, it cannot be applied. Summary of the invention

SUMMARY OF THE INVENTION The object of the present invention is to provide a method for measuring the wall thickness of a large-diameter hot-extruded tee, in order to establish a critical dimension database of the wall thickness of each part of the tee, which is convenient for later computer simulation and related pipe fitting performance prediction analysis.

In order to solve the above technical problems, the present invention provides a method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding, comprising the following steps:

(1) simplifying the geometric size and thickness of the tee;

(2) At the end of the branch of the tee, the longitudinal section through the three-way axis is zero. Section, then rotate to determine other longitudinal sections by angle;

(3) taking the end of the branch pipe end weld as the origin, and equally dividing the contour line by the equal length on the outer contour line of the cross section;

(4) cutting out the outer contour curve of the section by using a cardboard, measuring the thickness of the wall of each measuring point on the outer contour curve of the section by using the thickness of the aliquot as a measuring point, and then recording the paper with paper The outer contour curve of the cut out of the cardboard, and mark each measuring point on the outer contour curve. The Ge t Da ta software is used to establish the rectangular coordinate system and the coordinate values of each measuring point are obtained. The coordinate values of each measuring point are input into AutoCAD. Connecting each measuring point to generate an outer contour line; (5) drawing the wall thickness points of the measuring points on the outer contour line of the section through the AutoCAD to find the foot, and connecting the thickness points of each tube wall to generate the inner corridor line;

(6) a cross-sectional CAD drawing of the three-way cross-section is obtained from the inner contour line and the outer contour line; and the cross-section CAD drawing of the other cross-section of the three-way is obtained according to the above method;

(7) According to the CAD drawing of the cross section of the three-way cross section, the curvature of the intersection surface of the main branch pipe can be determined, 0. 90. The curve chamfer curvature is the curvature of the intersection surface of the main branch pipe, while the curvature of the intersection surface of the main branch pipe is modeled by the curve chamfer of 0° and 90°, which is determined by the average value of the radius of each arc.

Further, the angles determined by the angles are 0°, 15°, 30°, 45°, 60 in the other longitudinal sections. , 75. 90. .

Further, the equal length in the outer contour curve is equally divided into 20 mm on the outer contour curve of the section.

Further, the simplification of the geometry and thickness of the tee includes:

1) simplifying the shape of the three-way main branch into a standard cylindrical shape;

2) simplifying the wall thickness of the end portion of the three-way branch pipe to a uniform wall thickness, and taking an average value of the measured wall thickness;

3) simplifying the main section of the tee to a circle with an outer contour and an ellipse;

4) The method for simplifying the shoulder chamfer thickness of the tee is as follows: the angle and the outer contour measured by the field are used to draw various angle sections, and the chamfer radius inside and outside the section is measured, which can be modeled by So l idWorks software. Automatically establish a variable radius chamfer;

5) simplifying the main branch pipe short section of the three-way to a standard cylinder;

6) Simplify the main branch head of the tee into a standard semi-ellipsoid.

The measuring method of the large-diameter hot-extruding three-way wall thickness provided by the invention is based on the forming process characteristic of the hot-extruding tee, based on the actual measurement of the variation law of the hot-extruded three-way wall thickness, according to the tee The variation of the diameter of the wall thickness establishes the wall thickness database of the key parts of the hot extrusion forming tee. Make up for ANS I B16. 9 The pipe code has no requirements for the size and overall shape of the three-way main and branch transitions. Moreover, the measuring method of the invention not only needs to replace the fixture for different thickness samples, has high working efficiency and small test error, and can conveniently and quickly measure the same specification hot extrusion molding of different manufacturers, different production processes and different mold production. The geometrical dimensions of the three parts are not exactly the same, especially suitable for measuring the radius of curvature of the three-way different wall thickness and the three-way main branch transition.

1 is a simplified schematic view showing the geometric size and thickness of a hot-rolled tee of a DN1200 X 900 model in a method for measuring a large-diameter hot-extruded three-way wall thickness according to an embodiment of the present invention.

2 is a schematic cross-sectional view showing a thickness measurement in a method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding according to an embodiment of the present invention.

Fig. 3 is a cross-sectional view taken at 0° of the method for measuring the wall thickness of a large-diameter hot-extruded tee according to an embodiment of the present invention.

4 is a 30° cross-sectional view of a method for measuring a three-pass wall thickness of a large-diameter hot-extruding die according to an embodiment of the present invention.

Fig. 5 is a 45° sectional view of a method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding according to an embodiment of the present invention.

Fig. 6 is a cross-sectional view showing a 60° section of a method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding according to an embodiment of the present invention.

Figure Ί is a 90° cross-sectional view of a method for measuring the wall thickness of a large-diameter hot-extruded tee provided by an embodiment of the present invention. detailed description Referring to FIG. 1, a method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding according to an embodiment of the present invention includes the following steps:

(1) simplifying the geometry and thickness of the tee;

(2) At the end of the branch of the tee, the longitudinal section through the three-way shaft line is zero. Section, then rotate to determine other longitudinal sections by angle;

(3) Taking the end of the branch pipe end weld as the origin, and dividing the contour line by the equal length in the outer contour line of the cross section;

(4) Cut the outer contour curve of the section with cardboard, measure the wall thickness of each measuring point on the outer contour curve of the section with a thickness gauge of equal measuring length, and then use paper to record the section cut out of the cardboard. Contour curve, and mark each measuring point on the outer contour curve, use GetData software to establish a rectangular coordinate system and obtain the coordinate values of each measuring point, input the coordinate values of each measuring point into AutoCAD, connect each measuring point to generate the outer contour of the measuring point ;

(5) The wall thickness points of each measuring point on the outer contour line of the section are drawn by AutoCAD to find the vertical foot, and the thickness points of each pipe wall are connected to generate the inner contour line of the section;

(6) The CAD drawing of the cross section of the three-way section can be obtained from the inner contour line and the outer contour line; and the CAD drawing of the cross section of the other cross section of the three-way can be obtained according to the above method;

(7) According to the CAD drawing of the cross section of the three-way cross section, the curvature of the intersection surface of the main branch pipe can be determined, 0. 90. The curvature of the curved line is the curvature of the intersection of the main branch, while the curvature of the intersection of the main branch of the remaining angle is 0°, 90. The curve chamfering model is determined by the average of the radius of each arc.

Among them, the angles in other longitudinal sections are determined by angles as 0°, 15°, 30°, 45°, 60°, 75°, 90. .

Wherein, the aliquot length in the outer contour curve is equal to 20 mm in the outer contour curve of the section. Among them, the simplification of the geometry and thickness of the tee includes:

1) Simplify the shape of the three-way main branch pipe into a standard cylindrical shape;

2) Simplifying the wall thickness of the end of the branch of the tee to a uniform wall thickness, taking the average value of the measured wall thickness;

3) Simplify the main section of the tee to a circle with an outer contour and an ellipse;

4) The simplified method of the shoulder chamfer thickness of the tee is as follows: The angle and the outer contour measured by the field are used to draw the angle profiles of each angle, and the chamfer radius inside and outside the section is measured. The model can be automatically changed when modeling by Sol idWorks software. Radius chamfer

5) Simplify the main branch pipe short section of the tee into a standard cylinder;

6) Simplify the main branch head of the tee into a standard semi-ellipsoid.

The following is an example of the hot-extrusion tee of the DN1200 X 900 model. The method for measuring the wall thickness of the large-diameter hot-extrusion tee provided by the present invention is described in detail. The C=889mm of the hot-extrusion tee of the DN1200 X900 model is described. , M = 787mm.

See Figure 1. Simplification of the geometry and thickness of the hot-extruded tee of the DN1200 x 900 model

(1) The shape of the three-way main branch pipe is simplified. Due to the bulging extrusion process in the hot extrusion production process, the shape of the three-way main branch pipe is not a very standard cylindrical shape, so the shape of the main branch pipe is simple for the model. Simplified into a standard cylindrical shape.

(2) The thickness of the branch pipe is simplified. From the analysis of the measured thickness, the wall thickness of the branch pipe is simplified to the wall thickness of the hook wall, and the average value of the measured wall thickness is taken.

(3) The thickness of the main pipe is simplified. The thickness of the main pipe end is shown as being large and small, and the thickness is flat and excessive from top to bottom. Therefore, the main end section is simplified into two non-concentric circles, and the inner center of the circle is directly below the center of the outer circle. . The thickness analysis of the cross section of the tee cross section shows that the thickness of the left and right sides is the largest and the thickness of the bottom is the smallest. Therefore, the main section of the cross section of the tee is simplified to a circle with an outer contour and an inner ellipse.

(4) The simplification of the thickness of the shoulder chamfer, the thickness measured by the site and the outer wheel gallery are drawn at various angles. The chamfer radius inside and outside the section is measured, and the variable radius chamfer can be automatically established when modeling with So l idWorks software.

(5) Simplification of the short section of the main branch pipe. According to the thickness measured at the site, the thickness of the short section of the main branch pipe is uniform, so it is simplified to a standard cylinder.

(6) Simplification of the main branch pipe head. According to the thickness measured at the site, the thickness of the main branch pipe head is uniform, so it is simplified to a standard semi-ellipsoid.

Referring to Fig. 2, the longitudinal section of the branch pipe at the end of the tee is 0 through the three-way axis. Cross section, then rotate clockwise and select 15 respectively. Angles of 30°, 45°, 60°, 75°, 90° are used to determine other longitudinal sections measured.

Referring to Figures 3, 4, 5, 6, and 7, the sections are 0°, 30°, 45°, 60°, and 90, respectively, generated from the measured curves and corresponding thicknesses on the outer surface. Section. The steps of generating the inner surface curve and the section of each section are as follows: the outer contour curve on the surface of each cross section of the tee is cut out by cardboard, and the thickness of each point on the outer contour curve is measured by an ultrasonic thickness gauge every 20 mm as a measuring point. Then copy the cardboard outline paper, and point out the various measuring points. Use the Ge tDa ta software to establish the Cartesian coordinate system and obtain the coordinate values of each measuring point. Enter the coordinate values of each measuring point into AutoCAD, and use each point. The smooth curve connection is the outer contour line; then the thickness of each point measured by the thickness gauge is drawn in CAD by AutoCAD and then connected with the spline spl ing, which is the inner contour line. Once the inner and outer contours are generated, the section of the angle is obtained. According to DNU OO x 900 model hot extrusion three-way control sectional view, 0°, 90° curve chamfer curvature is the curvature of the main branch pipe intersection surface, and the remaining angle curve curvature is not the curvature of the main branch pipe interface, so press 0° , 90° chamfer modeling. The chamfer radius is determined by the average of the radius of each arc. Obtain 0° average outer chamfer radius of curvature, average inner chamfer radius of curvature; 90° average outer chamfer radius of curvature, average inner chamfer radius of curvature. The actual outer diameter of the main pipe, 0° curve corresponds to the thickness of the main pipe end, the thickness of the lower part of the main pipe, the outer diameter of the pipe branch, the actual 787mm, C=889mm, the total length between the ends of the main pipe, The distance from the branch head to the center of the tee. The length of the main head and the length of the branch head. The present invention has been described in detail with reference to the embodiments of the invention, and it should be understood by those skilled in the art Within the scope of the claims of the present invention.

Claims

Claim

A method for measuring a three-pass wall thickness of a large-diameter hot extrusion molding, comprising the steps of:

(1) simplifying the geometric size and thickness of the tee;

(4) cutting out the outer contour curve of the section by using a cardboard, measuring the thickness of the wall of each measuring point on the outer contour curve of the section by using the thickness of the aliquot as a measuring point, and then recording the paper with paper The outer contour curve of the cut out of the cardboard, and mark each measuring point on the outer contour curve, use Get Data software to establish the rectangular coordinate system and obtain the coordinate values of each measuring point, input the coordinate values of each measuring point into AutoCAD, connect each The measuring point generates an outer contour line of the section;

(5) drawing the wall thickness points of the measuring points on the outer contour line of the section through the AutoCAD to find the vertical foot, and connecting the thickness points of each tube wall to generate the inner contour line of the section;

(6) A cross-sectional CAD drawing of the three-way cross-section is obtained from the inner contour line and the outer contour line; and the cross-sectional CAD drawing of the other cross-section of the three-way is obtained according to the above method;

2. The method for measuring the wall thickness of a large-diameter hot-extruded tee according to claim 1, wherein the angle is determined to be 0° and 15 in the other longitudinal sections. 30. 45. 60. , 75°, 90. .

3. The method for measuring the wall thickness of a large-diameter hot-extruded three-way according to claim 1, wherein: said equal-length length in the outer contour curve is equally divided by an equal division length on the outer contour curve of the section It is 20mm.

4. The method for measuring the wall thickness of a large-diameter hot-extruded tee according to claim 1, wherein: the simplification of the geometrical dimensions and thickness of the tee comprises:

4) The simplification method of the shoulder chamfer thickness of the three-way is as follows: the angle and the outer contour measured by the scene are used to draw various angle sectional views, and the inner and outer chamfer radii of each section are measured, which can be automatically modeled by Sol idWorks software. Establish a variable radius chamfer;

6) Simplify the main branch head of the tee into a standard semi-ellipsoid.