Method for measuring welding precision of welded blisk joint

Abstract

The invention provides a method for measuring the welding precision of a welded blisk joint, and the method comprises the steps: building a joint and blisk measurement coordinate system according to a welding technology; in the welding process, a welding machine machining coordinate system and a blisk design coordinate system coincide, a detected welding joint is provided with three planes perpendicular to one another, and therefore a space coordinate system of the joint is constructed. Constructing a conversion relation between a welding joint space coordinate system and a welding equipment machining coordinate system; deriving a welding joint space degree-of-freedom algorithm; development of a measurement program and realization of a welding joint spatial degree-of-freedom algorithm; and a set of circulating measurement program is compiled for establishing a blisk measurement coordinate system and collecting data of three reference surfaces of the welding joint. The method has the advantages that the measurement precision of the spatial position of the welded blisk joint is improved, real and accurate data are provided for improvement of a welding process, and the method has wide market prospects and huge economic benefits.

Description

Technical Field

[0001] The invention relates to the field of welded integral blade disk measurement, and in particular to a method for measuring the welding accuracy of a welded integral blade disk joint. Background Art

[0002] The welding of integral blade disks is a processing method that forms single blades and disk bodies by welding. The welding accuracy of single blades directly affects the position accuracy of the blades of the integral blade disk. The conventional measurement method is: three-coordinate measurement of the cross-sectional position of the blade profile after welding, which indirectly characterizes the position error of the weld. Since the measured section is far from the weld, the position deviation of the single blade processing itself, and only three degrees of freedom deviation can be characterized, this method cannot accurately characterize the welding accuracy, and the feedback parameters cannot be used to adjust the welding process. Summary of the invention

[0003] The purpose of the present invention is to develop a measurement algorithm suitable for the welded layer integral blade disk joint, realize the automatic evaluation of the 6-DOF deviation of the welded layer integral blade disk joint position space, improve the measurement accuracy and welding process adjustment efficiency, and provide a welding accuracy measurement method for the welded integral blade disk joint.

[0004] The present invention provides a method for measuring the welding accuracy of a welded integral blade disk joint, which is characterized by:

[0005] (1) According to the welding process, establish the measurement coordinate system of the joint and the entire blade

[0006] During the welding process, the welding machine processing coordinate system coincides with the overall blade disk design coordinate system. The welded joint under test has three mutually perpendicular planes, from which the spatial coordinate system of the joint is constructed.

[0007] (2) Construct the conversion relationship between the welding joint space coordinate system and the welding equipment processing coordinate system

[0008] There are many conversion relationships from the welding equipment processing coordinate system to the welding joint space coordinate system, first translation and then rotation, or first rotation and then translation, and there are six rotation orders, namely XYZ, XZY, YZX, YXZ, ZXY, and ZYX; this patent uses the order of "XYZ rotation + translation", and the reference of rotation and translation is always relative to the welding equipment processing coordinate system, that is, the reference of the integral blade disk design coordinate system.

[0009] (3) Derivation of the algorithm for the spatial degrees of freedom of welded joints

[0010] Firstly, a characteristic intersection is constructed using three mutually perpendicular planes of the welding joint. The coordinate value of this point in the welding machine processing coordinate system is the three translation amounts of the welding joint. Then, the geometric relationship between the vector values ​​(i, j, k) of the three planes and the three coordinate axis directions of the welding machine processing coordinate system is used to derive the transformation relationship characterizing the three rotation amounts of the welding joint, thus completing the mathematical calculation method of the six degrees of freedom of the welding joint space.

[0011] (4) Development of measurement program and implementation of spatial freedom algorithm for welded joints

[0012] A set of cyclic measurement programs was compiled to establish the measurement coordinate system of the integral blade disk and collect the data of the three reference planes of the weld joint. The above algorithm for deriving the spatial degrees of freedom of the weld joint was developed into executable code using a high-level measurement language. This enables the automatic measurement and evaluation of the 6-degree-of-freedom deviation of the integral blade disk joint position in the weld layer.

[0013] According to the structural characteristics of the welded integral blade disk joint and the characteristics of the welding process, the present invention designs geometric parameters that characterize the spatial position of the welded integral blade disk joint, and refers to the process parameters of the welding machine to adjust the spatial posture of the welding joint. A measurement algorithm for the welded integral blade disk joint under a dual coordinate system is developed to realize automatic evaluation of the 6-degree-of-freedom deviation of the position of the welded layer integral blade disk joint space, thereby improving the measurement accuracy and the efficiency of welding process adjustment.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] The welding accuracy measurement method of the welded integral blade disk joint described in the present invention realizes the automatic evaluation of the 6-DOF deviation of the welded layer integral blade disk joint position space, and improves the spatial position measurement accuracy of the welded integral blade disk joint, providing real and accurate data for welding process improvement, and can be extended to different types of welded integral blade disk measurements and integral blade disk repair processes, and has broad market prospects and huge economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0017] Figure 1 It is a schematic diagram of the welding machine processing coordinate system and the welding joint coordinate system;

[0018] Figure 2 This is a schematic diagram of coordinate system transformation;

[0019] Figure 3 This is a schematic diagram of the projection geometric relationship after rotating the X-axis three times;

[0020] Figure 4 is a schematic diagram of a measuring needle assembly;

[0021] Figure 5Schematic diagram of the theoretical measurement trajectory points for generating blade profiles. DETAILED DESCRIPTION

[0022] The present invention will be further explained below in conjunction with specific implementation plans, but the present invention is not limited thereto. The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the restrictive conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0023] like Figure 1 As shown in the figure, during the welding process, the overall blade disk design coordinate system coincides with the welding machine processing coordinate system Datum(0). The three theoretical planes perpendicular to each other at the blade joint to be welded constitute the coordinate system Datum(1) theory, and the actual coordinate system Datum(1) is constructed from the actual three planes. The six degrees of freedom in the welding joint space are the conversion amount between the coordinate system Datum(0) and the Datum(1) theory. The welding accuracy is the conversion amount deviation between the coordinate system Datum(0) and the Datum(1) actual, as shown in the figure. Figure 2 shown.

[0024] Known conditions:

[0025] The original coordinate system Datum(0) and the transformed coordinate system Datum(1);

[0026] The three axes of Datum(1) are ijk (see Figure 2 ):

[0027] X-axis vector: X_i, X_j, X_k;

[0028] Y axis vector: Y_i, Y_j, Y_k;

[0029] Z axis vector: Z_i, Z_j, Z_k;

[0030] And the coordinate values ​​of the origin of coordinate system Datum(1) in coordinate system Datum(0): Tx, Ty, Tz

[0031] The transformation relationship of translation:

[0032] The translation is relatively simple to obtain. You can directly read the coordinate value of the origin of the coordinate system Datum(1) in the coordinate system Datum(0), which is the known Tx, Ty, and Tz. Since the order of transformation is "XYZ rotation + translation", the last step is translation. We will translate first by inverse budget. In the Datum(0) coordinate system, translate the origin of Datum(1) (left side) along the XYZ axis (right side) by -Tx, -Ty, and -Tz respectively. In this way, the origins of the two coordinate systems coincide with each other. See Figure 2 .

[0033] The transformation relationship of the rotation amount:

[0034] First, assume that the rotation angles are: α (around X); β (around Y); γ (around Z). α, β, γ are all plane angles and are located in the coordinate system Datum (0) plane YOZ, XOZ and XOY respectively. The actual meaning of ijk (taking the X axis as an example, see Figure 3 ):

[0035] The space straight line OC (see Figure 3 ) and the cosine of the angle between the three coordinate axes XYZ, that is:

[0036] X_i=Cos(∠COX); X_j=Cos(∠COY); X_k=Cos(∠COZ);

[0037] The three angles ∠COX, ∠COY, and ∠COZ are all spatial angles.

[0038] Transformation analysis (β):

[0039] Since the starting axis of rotation is around the X axis, it is relatively simple to analyze the transformation of the X axis in the coordinate system. All the axes and planes to be analyzed are in Datum(0). The analysis is as follows: The first rotation (around the X axis): the X axis line does not change, that is, OX rotates to OX; The second rotation (around the Y axis): the line OX rotates to OD, and OD is located in the plane XOZ; The third rotation (around the Z axis): the line OD rotates to OC, and OC is located in the coordinate system space. OX, OD, and OC are the positions of the same line (X axis) under different rotations. The third step is regarded as the plane XOZ rotating around the Z axis to the plane BOZ, and the line OD in XOZ also becomes OC in the plane BOZ as it rotates around the Z axis.

[0040] From this we can know that: (the angle between the straight line OD and the straight line OC and Z does not change during the process of going around Z) space angle ∠COZ = plane angle ∠DOZ………………………………①

[0041] As can be seen from the figure, ∠AOD is the angle β of the coordinate system rotating around Y:

[0042] ∠AOD = β ……………………………………………………………… ②

[0043] ∠AOD + ∠DOZ = 90° ………………………………………… ③

[0044] β+∠COZ=90°……………………………………………………④

[0045] The cosine value X_k of the angle between the straight line OC and the Z axis is a known quantity:

[0046] X_k =Cos(∠COZ)……………………………………………… ⑤

[0047] From trigonometric functions, we know that: Sin(β)=Cos(∠COZ)=X_k

[0048] β= arcsin(X_k)……………………………………………… ⑥

[0049] In this way, we can directly calculate the angle β of the coordinate system rotation around the Y axis in this transformation.

[0050] Similarly, if Figure 3 , CA⊥OA……………………………………⑦

[0051] According to the triple cosine theorem, we can know that:

[0052] Cos(∠AOC)=cos(∠AOB)* cos(∠BOC)…………………… ⑧

[0053] γ=arccos(X_i / cos(β))…………………………………… ⑨

[0054] From the rotation transformation, we can know that:

[0055] ∠AOC=∠BOD=α; ∠DOC=β

[0056] Similarly, ⑦⑧ can be known (three cosine theorem):

[0057] Cos(∠BOC)=cos(∠BOD)*cos(∠DOC)

[0058] Cos(∠BOC)=cos(α)*cos(β)

[0059] Cos(∠BOC) is the cosine value of the angle between the transformed Z axis (OB) and the Z axis in the coordinate system Datum(0), that is, Z_k. So: α=arccos(Z_k / cos(β))………………………………1○0

[0060] (1) Figure 1 As shown in the figure, taking the welding integral blade disk with a diameter of 800mm and 26 blades as an example, select a measuring machine with accuracy that meets the requirements, and the measuring software is Modus1.9 version. Combined with the measurement benchmark information and the size of the welding joint of the blade to be welded, select Figure 4 The stylus shown has a stylus assembly with a stylus ball diameter of 6mm, an effective measuring length of 50mm and a stylus stem length of 350mm.

[0061] (2) Create a new programming project, compile a measurement benchmark program based on the design benchmark of the integral blade disk, and generate Datum(0), which is the welding machine processing coordinate system. In the Datum(0) coordinate system, press Figure 5 The measurement points of the three reference surfaces are collected at the positions shown to generate the actual coordinate system of Datum (1). The main program code generated is as follows:

[0062] Define three planes

[0063] DPLN=ASSIGN / CONCAT('DPLN_',blade_number_cha)

[0064] FPLN=ASSIGN / CONCAT('FPLN_',blade_number_cha)

[0065] EPLN=ASSIGN / CONCAT('EPLN_',blade_number_cha)

[0066] Based on the Datum(0) coordinate system, construct the actual coordinate system of the welding joint Datum(1)

[0067] RECALL / DA(INTER_DATUM)

[0068] DATDEF / FA(FPLN),DAT(F)

[0069] D(23)=DATSET / DAT(F),ZDIR,ZORIG

[0070] CONST / LINE,F(LINE002),INTOF,FA(FPLN),FA(DPLN)

[0071] D(27)=ROTATE / ZAXIS,FA(LINE002),XDIR

[0072] D(26)=TRANS / YORIG,FA(DPLN)

[0073] D(22)=TRANS / XORIG,FA(EPLN)

[0074] The D(22) coordinate system is the Datum(1) actual coordinate system

[0075] (3) Generate translation program code:

[0076] In the Datum(0) coordinate system, the Datum(1) theoretical coordinate system is constructed by three theoretical translations and three rotations: D(8) = TRANS / XORIG,-120,YORIG,60,ZORIG,200

[0077] D(9)=ROTATE / YAXIS,-45

[0078] D(10)=ROTATE / ZAXIS,-30

[0079] Define the origin of the weld joint coordinate point

[0080] F(PNT_0)=FEAT / POINT,CART,0,0,0,0,0,1

[0081] FA(PNT_0)=FEAT / POINT,CART,0,0,0,0,0,1

[0082] Output the deviation of the point in the Datum(1) actual coordinate system

[0083] T(53)=TOL / CORTOL,XAXIS,-0.1,0.1

[0084] T(54)=TOL / CORTOL,YAXIS,-0.1,0.1

[0085] T(55)=TOL / CORTOL,ZAXIS,-0.1,0.1

[0086] OUTPUT / FA(PNT_0),TA(53),TA(54),TA(55) Output the translation of the origin of the welding joint coordinate point DECL / LOCAL,DOUBLE,DX,DY,DZ DY=OBTAIN / TA(54),3

[0087] DX=OBTAIN / TA(53),3

[0088] DZ=OBTAIN / TA(55),3

[0089] DECL / LOCAL,CHAR,512,CHA_DX,CHA_DY,CHA_DZ CHA_DX=ASSIGN / CONCAT('DETAx:',STR(DX))CHA_DY=ASSIGN / CONCAT('DETAy:',STR(DY))CHA_DZ=ASSIGN / CONCAT('DETAz:',STR(DZ))TEXT / OUTFIL,'---DETA---'

[0090] TEXT / OUTFIL,CHA_DX

[0091] TEXT / OUTFIL,CHA_DY

[0092] TEXT / OUTFIL,CHA_DZ

[0093] (4) Generate rotation program code:

[0094] In the actual coordinate system of Datum (1), define the three coordinate axis direction lines F(LINE_X)=FEAT / LINE,UNBND,CART,0,0,0,1,0,0,0,-1,0FA(LINE_X)=FEAT / LINE,UNBND,CART,0,0,0,1,0,0,0,-1,0F(LINE_Y)=FEAT / LINE,UNBND,CART,0,0,0,0,1,0,1, 0,0FA(LINE_Y)=FEAT / LINE,UNBND,CART,0,0,0,0,1,0,1,0,0F(LINE_Z)=FEAT / LINE,UNBND,CART,0,0,0,0,0,1,0,-1,0FA(LINE_Z)=FEAT / LINE,UNBND,CART,0,0,0,0,0,1,0,-1,0Define the linear vector variable in the Datum(0) coordinate system

[0095] DECL / LOCAL,REAL,V_i,V_j,V_k,V_x,V_y,V_zDECL / LOCAL,REAL,L1_i,L1_j,L1_k,L1_x,L1_y,L1_zDECL / LOCAL,REAL,L2_i,L 2_j,L2_k,L2_x,L2_y,L2_zDECL / LOCAL,REAL,L3_i,L3_j,L3_k,L3_x,L3_y,L3_zDECL / DOUBLE,I1,J1,K1,I2,J2,K2,I3,J3,K3

[0096] V_x=OBTAIN / FA(PNT_T),3

[0097] V_y=OBTAIN / FA(PNT_T),4

[0098] V_z=OBTAIN / FA(PNT_T),5

[0099] L1_i=OBTAIN / FA(LINE_X),7L1_j=OBTAIN / FA(LINE_X),8L1_K=OBTAIN / FA(LINE_X),9L2_i=OBTAIN / FA(LINE_Y),7L2_j=OBTAIN / FA(LINE_Y),8L2_K=OBTAIN / FA(LINE_Y),9L3_i=OBTAIN / FA(LINE_Z),7L3_j=OBTAIN / FA(LINE_Z),8L3_K=OBTAIN / FA(LINE_Z),9

[0100] Generate program code to calculate three rotation quantities, formula 8 program code DECL / REAL,A1,B1,C1,ANGA,ANGB,ANGC,PI PI=ASSIGN / 3.1415926

[0101] ANGB=ASSIGN / Asin(L1_k)

[0102] B1=ASSIGN / RTOD(ANGB)

[0103] IF / (L1_k.LT.0.000000)

[0104] B1=ASSIGN / abs(B1)

[0105] ELSE B1=ASSIGN / -1*abs(B1)ENDIF

[0106] Formula 9 Program code C1=ASSIGN / L1_i / cos(ANGB)ANGC=ASSIGN / Acos(C1)C1=ASSIGN / 1*RTOD(ANGC)IF / (L1_j.LT.0.000000)C1=ASSIGN / -1*abs(C1)ELSE C1=ASSIGN / 1*abs(C1)ENDIF

[0107] Formula 10 Program code A1 = ASSIGN / L3_k / cos (ANGB) ANGA = ASSIGN / A cos (A1) A1 = ASSIGN / RTOD (ANGA) IF / (L2_k.LT.0.000000)

[0108] A1=ASSIGN / -1*abs(A1)

[0109] ELSE A1=ASSIGN / 1*abs(A1)

[0110] ENDIF

[0111] (5) Output welding joint measurement results

[0112] V_x=ASSIGN / -1*V_x+98

[0113] V_y=ASSIGN / 1*V_y

[0114] V_z=ASSIGN / 1*V_z

[0115] A1=ASSIGN / -1*A1

[0116] DECL / LOCAL,CHAR,512,CHA_Rx,CHA_Ry,CHA_Rz,CHA_Tx,CHA_Ty,CHA_Tz CHA_Tx=ASSIGN / CONCAT('Tx:',STR(V_Z))

[0117] CHA_Ty=ASSIGN / CONCAT('Ty:',STR(V_y))

[0118] CHA_Tz=ASSIGN / CONCAT('Tz:',STR(V_X))

[0119] CHA_Rx=ASSIGN / CONCAT('Rx:',STR(C1))

[0120] CHA_Ry=ASSIGN / CONCAT('Ry:',STR(B1))

[0121] CHA_Rz=ASSIGN / CONCAT('Rz:',STR(A1))

[0122] TEXT / OUTFIL,'---Rotation(Degree)---'

[0123] TEXT / OUTFIL,CHA_Rx

[0124] TEXT / OUTFIL,CHA_Ry

[0125] TEXT / OUTFIL,CHA_Rz

[0126] TEXT / OUTFIL,'---Translation---'

[0127] TEXT / OUTFIL,CHA_Tx

[0128] TEXT / OUTFIL,CHA_Ty

[0129] TEXT / OUTFIL,CHA_Tz

[0130] DECL / LOCAL,DOUBLE,DX,DY,DZ

[0131] Matters not covered by the present invention are known technologies.

[0132] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for measuring the welding accuracy of a welded integral blade disk joint, characterized in that: The steps include: (1) According to the welding process, establish the measurement coordinate system of the joint and the entire blade During the welding process, the welding machine machining coordinate system coincides with the overall blade disk design coordinate system. The welded joint under test has three mutually perpendicular planes, from which the spatial coordinate system of the joint is constructed. (2) Construct the conversion relationship between the welding joint space coordinate system and the welding equipment processing coordinate system There are many conversion relationships from the welding equipment processing coordinate system to the welding joint space coordinate system, first translation and then rotation, or first rotation and then translation, and there are six rotation orders, namely XYZ, XZY, YZX, YXZ, ZXY, ZYX; this patent uses the order of "XYZ rotation + translation", and the basis of rotation and translation is always relative to the welding equipment processing coordinate system, that is, the overall blade disk design coordinate system basis; (3) Derivation of the algorithm for the spatial degrees of freedom of welded joints Firstly, a characteristic intersection point is constructed by using three mutually perpendicular planes of the welding joint. The coordinate value of this point in the welding machine processing coordinate system is the three translation amounts of the welding joint. Then, the geometric relationship between the vector values ​​(i, j, k) of the three planes and the three coordinate axis directions of the welding machine processing coordinate system is used to derive the transformation relationship that characterizes the three rotation amounts of the welding joint, thus completing the mathematical calculation method of the six degrees of freedom of the welding joint space. (4) Development of measurement program and implementation of spatial freedom algorithm for welded joints A set of cyclic measurement programs was compiled to establish the measurement coordinate system of the entire blade disk and collect data on the three reference surfaces of the weld joint. The above-mentioned algorithm for deriving the spatial degrees of freedom of the weld joint was developed into executable code using a high-level measurement language. This enabled automatic measurement and evaluation of the six-degree-of-freedom deviation of the joint position of the weld layer in the entire blade disk.

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